V5FPH Cover.qxd 12/11/03 9:00 am Page 1

Uniclass EPIC L5:P2:N32 E:X2:Y421 CI/SfB Rf9 (K2)+(K3)

December 2003

NBSPlus The Passive Handbook FIRE RATED DUCTWORK ● Ventilation and Smoke Extraction Ducts ● Cable Protection ● Mechanical and Electrical Service Enclosures 6 VENTILATION & SMOKE EXTRACTION DUCTS The Fire Protection Handbook

The relative complexity of any ductwork system which is extract, should also have this criterion for the inner surface of passing through different fire compartments and the relevance the within the fire compartment when the duct is exposed of the system’s function in ambient and fire conditions can to external fire (Duct A). make the selection of a suitable ductwork system difficult. For smoke extraction, the guidance in the standard states that This section of the handbook aims to give guidance on the the cross sectional area of a duct required to extract smoke in fire performance requirements of ductwork and offers a wide the event of a fire should not be reduced by more than 25%. range of solutions for proprietary “off the shelf” fire rated ductwork, the protection of steel ductwork and for self- Design Considerations supporting systems using PROMATECT®-L500 and The following points are some of the factors which should VICUCLAD®. be considered when determining the correct specification to ensure a ductwork system will provide the required fire For particularly onerous conditions e.g. where a high performance. Further advice can be obtained from the Promat impact strength is required or for use in aggressive Technical Services Department. environments, Promat have developed a range of systems using DURASTEEL®. 1. Required Fire Exposure Ductwork systems which are located in more than one Fire Testing Methods compartment should always be tested or assessed for their To determine the fire resistance of ducts (without the aid of performance when exposed to the heating conditions of fire dampers) passing through or between compartments, the BS 476: Part 20: 1987. Reduced heating curves are system should normally be tested or assessed in accordance generally only acceptable for certain components of the 6 with BS 476: Part 24: 1987. This standard has been written system e.g. the . specifically for ventilation ducts, but guidance is also given The performance of a ductwork system will vary depending in the standard on the performance requirements for ‘smoke on whether or not a fire could have direct access to inside outlet’ ducts and ‘kitchen extract’ ducts. the duct through an unprotected opening. If in doubt, one

Tested duct systems are exposed to external fire (Duct A) should assume it can i.e. the Duct B scenario described and internal fire (Duct B). Fans create a standard pressure previously under Fire Testing Methods. difference and air flow and the ducts fire performance is 2. Required Fire Performance assessed in both the fan-on and the fan-off situations. It is normally required to satisfy all the relevant performance When testing horizontal ducts, a run of at least 3m is located criteria of stability, integrity and insulation (and cross within the fire compartment and a further 2.5m outside the sectional area if a smoke extraction duct). However, the fire compartment. approval authority may accept a relaxation on occasions. For example, if no combustible materials or personnel BS 476: Part 24: 1987 expresses the fire resistance of ducts could be in contact with the duct, the authority may accept without the aid of dampers, in terms of stability, integrity and a reduced insulation performance. insulation. Stability failure occurs when the suspension or fixing devices can no longer retain a duct in its intended position or 3. Supporting Structure when sections of the duct collapse. This requirement does not Any structural element that the ductwork system is apply to the length of the duct exposed to internal fire (Duct B) supported from e.g. a beam, floor or wall, must have at within the fire compartment. least the same fire resistance as the duct system itself.

Integrity failure occurs when cracks, holes or openings occur 4. Hanger Support in the duct or at any penetrations through walls or floors, which The hangers, supports and their fixings should be flames or hot gases can pass. The effects on integrity of the capable of bearing the load of the complete ductwork movement and distortion of both restrained and unrestrained system including any applied insulation material or other ducts are also included in the standard. services suspended from it. Chemical anchors are not generally suitable. It is generally not advisable to use Insulation failure occurs when the temperature rise on the outer unprotected supports if the stress exceeds the values surface of the duct, outside the fire compartment, exceeds given on page 102 and/or if hanger lengths exceed 2m. 140°C (mean) or 180°C (maximum). The guidance in The hanger centres should not exceed the limits given the standard also states that ducts lined with combustible in the following pages for the relevant system. materials or coated internally with fats or greases e.g. kitchen

THE HANDBOOK PROMAT UK LIMITED

98 VENTILATION & SMOKE EXTRACTION DUCTS The Fire Protection Handbook

5. Steel Ductwork The steel duct must be constructed in accordance with the requirements of DW144 – Specification for sheet metal ductwork (published by the Heating and Ventilating Contractors’ Association), or equivalent specification.

6. Penetrations through Walls & Floors Care should be taken to ensure that movement of the duct in ambient or in fire conditions does not adversely affect the performance of the wall, partition or floor, or any penetration seal.

7. Movement Joints Movement joint details may be required for long lengths of duct, particularly where the duct spans across a movement joint in the floor or wall, or passes through floors or a roof that may deflect at different rates.

8. Air Flow & Leakage The design of some fire resisting duct systems may need modification to meet DW144 performance standards.

9. Ductwork Functions 6 Most ductwork systems can fall into one or more of the following categories: ● Ventilation and ; ● Natural smoke extract; ● Fan assisted smoke extract; ● Pressurisation of escape routes and fire fighting lobbies. Selection of Fire Protection System ● Non-domestic kitchen extract Traditionally all ductwork was fabricated from steel which In the event of a fire, the function of a system can often normally had to be encased in a fire protection system when alter. For example, an air conditioning system could switch passing through a compartment wall or floor without the aid of to become a fan assisted smoke extract duct. It is a fire . therefore essential that the performance requirements in both normal conditions and fire conditions are considered. In recent years, self-supporting systems without a steel liner, like VICUVENT®, have been introduced to extract smoke in the 10. Other Requirements event of a fire through natural ventilation, and now self- Acoustic performance, , water tolerance, supporting systems e.g. PROMATECT®-L500 and strength and appearance can also be important DURASTEEL®, are available which can match the leakage and considerations. air flow performance of steel ducts in accordance with DW144 up to Class C.

To satisfy the wide range of requirements in the current market, Promat can offer no less than four products to protect steel ductwork and three products to fabricate self-supporting systems.

The system selector on the next page should assist in determining the correct ductwork system to meet your needs and further guidance can be obtained from the Promat Technical Services Department.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

99 VENTILATION & SMOKE EXTRACTION DUCTS The Fire Protection Handbook

DESIGNER SELECTOR TABLE Cladding of Existing Metal Sheet Ducts Product Advantages Maximum Maximum Classification Duct Size (mm) ** DW144 * (width x height) VICUCLAD® ● Lightweight Depends on 3000 x 1500 Lightweight boards, ● Easy to work steel duct. oatmeal colour, bonded and nailed ● Small board size to each other and to spacer battens. ● Non-combustible For ducts greater than 900mm ● Water tolerant wide, framing usually required.

PROMATECT®-L500 ● Lightweight Depends on 6000 x 1500 Lightweight ● Large board size steel duct boards, off-white colour, stapled ● Appearance or screwed to each other and ● Non-combustible to spacer battens. ● Water tolerant

SUPALUX® ● Large board size Depends on 3000 x 1000 Robust calcium silicate board, ● Low board thickness steel duct. off-white colour, screw fixed to light ● Appearance galvanised angle and channel ● Non-combustible 6 framework. ● Water tolerant

Note: PROMALIT® - an inert board may also be used to fire protect metal sheet ductwork. Please contact Promat Technical Services Department for further specifications.

Self-Supporting Ducts Product Advantages Maximum Maximum Classification Duct DW144 * Size (mm) **

PROMATECT®-L500 ● Appearance DW144 3000 x 1250 Lightweight calcium silicate ● Prefabricated HIGH PRESSURE boards, off-white colour, stapled or ● Non-combustible Class C screwed and glued to each other. ● Water tolerant

DURASTEEL® ● High impact strength DW144 6000 x 2000 Very robust panels with cement ● Loadbearing for HIGH PRESSURE based core and outer steel linings, foot traffic Class C screw fixed to steel framework. ● Non-combustible All joints filled with PROMASEAL® ● Water tolerant silicone sealant.

SUPALUX® ● Large board size DW144 3000 x 1250 Robust calcium silicate board, ● Low board thickness HIGH PRESSURE off-white colour, screw fixed to light ● Appearance Class C galvanised framework. ● Non-combustible ● Water tolerant

* May require stiffeners and increased board thickness. ** May require modifications to system.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

100 VENTILATION & SMOKE EXTRACTION DUCTS The Fire Protection Handbook

Product Thickness Stability Integrity Insulation Mineral Wool Remarks (mm) (mins) (mins) (mins)

VICUCLAD® 30 60 60 60 30mm x 60kg/m3 Insulation as Duct Type B. 35 30 30 30 Not required Exposed to external and internal fire. 35 90 90 90 30mm x 80kg/m3 40 120 120 120 40mm x 80kg/m3 50 180 180 180 50mm x 80kg/m3 70 240 240 240 60mm x 80kg/m3

PROMATECT®-L500 20 120 120 120 50mm x 100 kg/m3 Insulation as Duct Type B. 25 30 30 30 Not required Exposed to external and internal fire. 35 60 60 60 Not required 50 120 120 120 Not required 50 240 240 240 75mm x 100 kg/m3

® SUPALUX 9 120 120 0 Not required Insulation as Duct Type B. 12 240 240 0 Not required Exposed to external and internal fire. 15 120 120 120 50mm x 100 kg/m3 20 240 240 30 Not required 25 240 240 240 100mm x 100 kg/m3 6

For ducts exposed to external fire (Duct Type A) the insulation can be measured inside the duct, inside the fire compartment, or outside the duct on an adjacent compartment. All the above provide similar levels of insulation to that listed, when the insulation is measured outside the duct. For details of insulated ducts exposed to external fire where insulation is required inside the duct, or inside the fire compartment, please consult the Promat Technical Services Department.

Product Thickness Stability Integrity Insulation Mineral Wool Remarks (mm) (mins) (mins) (mins)

PROMATECT®-L500 25 30 30 30 Not required Insulation as Duct Type B. 35 60 60 60 Not required Exposed to external and internal fire. 52 240 240 120 Not required 52 240 240 240 50mm x 100 kg/m3

DURASTEEL LT®* 6303030 Not required Insulation as Duct Type B. 6606060 50mm x 60kg/m3 Exposed to external and internal fire. 6 120 120 120 80mm x 140kg/m3 Natural ventilation/ powered ventilation/ 6 180 180 180 100mm x 140kg/m3 smoke extraction/ kitchen extract. 6 240 240 220 120mm x 140kg/m3 Insulation applied when necessary DURASTEEL SMT®* 9.5 30 30 30 50mm x 60kg/m3 Insulation as Duct Type B. 9.5 60 60 60 50mm x 60kg/m3 Exposed to external and internal fire. 9.5 120 120 120 80mm x 140kg/m3 Natural ventilation/ powered ventilation/ 9.5 180 180 180 100mm x 140kg/m3 smoke extraction. 9.5 240 240 220 120mm x 140kg/m3 Insulation applied when necessary SUPALUX® 20 120 120 30 Not required Insulation as Duct Type B 25 240 240 30 Not required Exposed to external and internal fire. 25 240 240 240 100mm x 100 kg/m3

*120 minutes kitchen extract system are also available, please contact Promat Technical Services Department.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

101 VENTILATION & SMOKE EXTRACTION DUCTS The Fire Protection Handbook

GENERAL INFORMATION For any size of duct, the tensile stress in the steel hangers If these stress levels are exceeded then the size of the hanger must not exceed 10N/mm2 for fire ratings up to 120 minutes, rods must be increased, or the centres of the hangers reduced or 6N/mm2 for fire ratings up to 240 minutes. The maximum or the hangers protected. The penetration of the hanger fixings permitted stress for each fire resistance period is based on into any concrete soffit should be a minimum of 50mm for BS 5950: Part 8: 1990. 120 minutes ratings or 65mm for 240 minutes ratings.

The method to calculate whether the diameter of the threaded rod is within the permitted stress level is given below.

Fire Resistance period Approximate Maximum permitted up to minutes Temperature °C tensile stress (N/mm2) 30 840 18 60 950 15 90 1000 10 120 1050 10 180 1110 6 240 1150 6

Maximum loads for drop rods 6 Nominal Tensile stress Load diameter area (BS 4190) 60 minutes (15N/mm2) 120 minutes (10N/mm2) 240 minutes (6N/mm2) (mm) (mm2) (kN) (kg) (kN) (kg) (kN) (kg) 6 20.1 0.30 30.73 0.20 20.49 0.12 12.29 8 36.6 0.55 55.96 0.37 37.31 0.22 22.39 10 58.0 0.87 88.690 0.58 59.12 0.35 35.47 12 84.3 1.26 128.90 0.84 85.93 0.51 51.56 16 157.0 2.36 240.06 1.57 160.04 0.94 96.02 20 245.0 3.68 374.62 2.45 249.75 1.47 149.85

VICUCLAD® General Installation Details VICUCLAD® can be installed by the following method, which is suitable for ducts exposed to either internal or external fire. 6 Variation in the method outlined is possible, but approval from 4 the Promat Technical Services Department should be sought 2 before alternative methods are used. In the following method, all joints between VICUCLAD® boards or battens should be fully filled with VICUBOND WR adhesive. Wherever possible nails should also be used at nominal 300mm centres. Nails should be twice as long as the board thickness.

Adhesive extruded from joints should be removed by a cutting action to ensure a neat, clean job without spreading adhesive on the board surface. In general, the width of a joint filled with 1 5 adhesive should be 1-3mm. 3

Installation Method

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

102 CLADDING OF EXISTING SHEET METAL DUCTS The Fire Protection Handbook

Adhesive should also completely fill joints between VICUCLAD® 4. VICUBOND® WR adhesive, with nails at nominal 300mm and adjoining elements unless differential movement is expected. centres, fully filling all joints. Nail length twice board In this case a suitable movement joint detail can be obtained thickness. from Promat Technical Services Department. Movement joints 5. Mineral wool if required fitted between battens (omitted for may be required for long lengths of duct particularly where clarity), refer to previous tables. the duct spans across a movement joint in the floor slab or walls or passes through floors or a roof that may deflect at NOTE: If the duct will only be exposed to external fire and it requires a fire resistance of 30 minutes, the spacer battens (3) and the mineral wool (5), different rates. are not needed and the encasement can be fitted tightly around the duct. If the duct flanges penetrate the casing, external VICUCLAD® cover strips TECHNICAL DATA should be secured over the joint. Maximum permissible width of ducting 240 minutes fire rating, integrity and insulation in given in table below (Duct height must not exceed duct width). . accordance with the criteria of BS 476: Part 24: 1987. VICUCLAD® thickness (mm) 25 30 35 40 45 50 70 1. Steel duct. Maximum duct width (mm) 900 880 860 840 820 800 720

2. VICUCLAD® board, secured following the general 6. Hanger diameter sized to limit stress depending on fire installation guidance given above. Board thickness in resistance period (See table on opposite page). accordance with the tables below.

Fire resistance (stability and integrity only) period 4 (minutes) 30 60 90 120 180 240 VICUCLAD® 6 thickness 2 (mm) 25 30 30 35 45 45 1 3 NOTE: The VICUCLAD® thicknesses given above will normally be adequate for all applications, including those where fire has direct access 6 to inside the duct. In the latter case, the approval authority would require to accept a reduced insulation performance. This relaxation is often acceptable if personnel or combustible materials will not be in contact with the outer surface of the duct. Detail 1 – Cross section through duct. Fire resistance (stability, integrity and insulation) period (minutes) VICUCLAD® Mineral wool thickness (mm) 30 35 — 4 2 3 6 60 30 30mm x 60 kg/m3 90 35 30mm x 80 kg/m3 120 40 40mm x 80 kg/m3 180 50 50mm x 80 kg/m3 240 70 60mm x 80 kg/m3

NOTE: If a fully developed fire could gain access to the inside of the duct, and at the same time combustible materials, or personnel, could be in contact with the outer surface of the duct encasement, the VICUCLAD® thicknesses and mineral wool given above are required unless the 1 approval authority accept a reduced insulation performance (kitchen extract specifications are available from the Promat Technical Services Department). Detail 2 – Longitudinal section through duct. 3. VICUCLAD® spacer battens at 610mm centres bonded and nailed to each other. Batten thickness same as outer casing. Batten width twice thickness. Batten centres may be increased to 1m after consultation with Promat Technical Services Department.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

103 CLADDING OF EXISTING SHEET METAL DUCTS The Fire Protection Handbook

PROMATECT®-L500 TECHNICAL DATA 120 minutes and 240 minutes fire rating, stability, integrity and insulation in accordance with the criteria of BS 476:

4 Part 24: 1987; internal or external fire. 3 1. PROMATECT®-L500 boards, thickness in accordance with 1 table on page 101.

2. Steel channel.

3. M4 self-tapping screws at approximately 200mm centres.

6 4. Hanger diameter and supports sized to limit stress,

5 in accordance with table on page 102. 5. Steel angles.

2 6. Steel duct in accordance with DW144.

7. PROMATECT®-L500 collar, thickness in accordance with Installation Method 1 table on page 101.

4 8. Mineral wool tightly packed into aperture between Detail 3 surrounding structure and the surface of the 3 6 PROMATECT®-L500 board. 2 6 NOTE: Fire resistant ducts can be formed where the substrate from which 1 4 the steel duct is supported provides protection to some areas, thus 1, 2 and 3-sided solutions in combination with walls and ceilings are available, 5 on request.

The above details are applicable for the construction of fire resistant Detail 1 – Cross section through duct. encasements around steel ducts up to 1500mm wide, however, PROMATECT®-L500 duct systems are approved for up to 6m wide. Variations on supporting components for duct width over 1500mm are available on request.

Detail 5 As an alternative fixing method, the angle at the corner and the channel at the butt joints can be replaced by PROMATECT®-L500 strips 25mm x 25mm and Detail 4 5 25mm x 50mm respectively. The installation time can usually be shortened by using steel staples at nominal 100mm centres instead of screws.

6

1 2 8 3

Detail 2 – Longitudinal wall penetration. 5 7

3 2 3 1

1 6

5 8

Detail 3 – Corner detail. Detail 4 – Butt joint detail. Detail 5

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

104 CLADDING OF EXISTING SHEET METAL DUCTS The Fire Protection Handbook

TECHNICAL DATA Up to 240 minutes fire rating, stability, integrity and 7 insulation in accordance with the criteria of BS 476: 2 Part 24: 1987; internal or external fire. 1 1. PROMATECT®-L500 boards, thickness in accordance with table on page 101. 3

2. SUPALUX® cover strips, 100mm wide x 9mm thick. 6 3. Mineral wool, requirement in accordance with table on page 101. 4. Steel duct in accordance with DW144. 5. For ducts up to 3000mm wide: Steel channel collar, 50mm x 50mm x 0.9mm thick, around 4 duct spaced at centres in accordance to the width of the 10 5 duct to ensure a maximum unsupported area not 8 exceeding 1.5m2. Installation Method 2 6. For ducts between 3000mm to 6000mm wide only: 2214 2 7 Additional support brackets at mid span. 5 (For more construction details for such ducts, 1 please refer to Promat Technical Services Department). 2 7. Hanger diameter sized and spaced to limit stress, 3 6 requirement in accordance with table on page 102. 4 8. M4 self-tapping screws at nominal 200mm centres. Detail 3 9. Corner steel angle, 30mm x 30mm x 0.6mm. 8 6 10. Mineral wool seal. Detail 1 – Cross section through duct. 11. PROMATECT®-L500 collar, requirement in accordance with table on page 101. 2 7 11 12. Galvanised C-channel framework, 50mm x 50mm x 0.9mm thick, at board butt joints with cavity void fully infilled with 5 mineral wool. For duct span up to 3000mm: 12 Galvanised C-channel, 50mm x 50mm x 0.9mm thick, 4 at board butt joints. For duct span between 3000mm to maximum 6000mm: Galvanised hollow section formed from 2 C-channels at 2214. 10

mid span. ➛ 13 13. Masonry wall or slab. Detail 2 – Longitudinal wall penetration. 14. M4 self-tapping screws at nominal 200mm centres. 1 1

8

2114 9

Detail 3 – Edge fixing Alternative fixing using steel angles.

NOTE: 1, 2 and 3-sided solutions in combination with walls and ceilings approved, details on request. The above ducts are approved up to 6m in width. More details of the supporting components are available on request.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

105 CLADDING OF EXISTING SHEET METAL DUCTS The Fire Protection Handbook

SUPALUX® TECHNICAL DATA 120 minutes and 240 minutes fire rating, stability, integrity and insulation in accordance with the criteria of BS 476: 4 Part 24: 1987; internal or external fire. 3 ® 1 1. SUPALUX boards, thickness in accordance with table on page 101.

2. Steel channel, 50mm x 25mm x 0.5mm, at butt joints.

3. M4 self-tapping screws at approximately 200mm centres 6 or steel wire staples, at nominal 100mm centres, sizes

5 dependent on board thickness. 4. Hanger diameter and supports sized to limit stress,

2 in accordance with table on page 102. 5. Steel angles, 25mm x 25mm x 0.6mm. Installation Method 1 6. Steel duct in accordance with DW144.

4 7. SUPALUX® collar, 150mm wide, thickness in accordance

3 with the table on page 101. 6 8. Mineral wool tightly packed into aperture between 2 6 substrate and the surface of the SUPALUX® board. 1 4

NOTE: Fire resistant ducts can be formed where the substrate from which 5 the steel duct is supported provides protection to some areas, thus 1, 2 and 3-sided solutions in combination with walls and ceilings are available Detail 1 – Cross section through duct. on request. The above details are applicable for the construction of fire resistant encasements around steel ducts up to 1500mm wide, however SUPALUX® duct systems are approved for up to 10m wide. Variations on supporting components for duct width over 1500mm are available on request.

As an alternative fixing method, the angle at the corner and the channel at the butt joints can be replaced by SUPALUX® strips 25mm x 25mm and 25mm x 5 50mm respectively. The installation time can usually be shortened by using steel staples at nominal 100mm centres instead of screws.

6

1 2 8 3

Detail 2 – Longitudinal wall penetration.

5 7

3 2 3 1

1 6

5 8

Detail 3 – Corner detail. Detail 4 – Butt joint detail. Detail 5

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

106 CLADDING OF EXISTING SHEET METAL DUCTS The Fire Protection Handbook

TECHNICAL DATA Up to 240 minutes fire rating, stability, integrity and 7 insulation in accordance with the criteria of BS 476: 2 Part 24: 1987; internal or external fire. 1 1. SUPALUX® boards, thickness in accordance with table on page 101. 3

2. SUPALUX® cover strips, 100mm wide x 9mm thick. 6 3. Mineral wool, requirement in accordance with table on page 101. 4. Steel duct in accordance with DW144. 5. For ducts up to 3m wide: Steel channel collar, 50mm x 50mm x 0.9mm, around 4 10 5 duct spaced at centres in accordance to the width of the duct to ensure a maximum unsupported area not 8 Installation Method 2 exceeding 1.5m2. 6. For ducts between 3000mm to 6000mm wide only: 2214 2 Additional support brackets at mid span. 7 (For more construction details for such ducts, 5 please refer to Promat Technical Services Department). 1 7. Hanger diameter and supports sized to limit stress, 2 6 in accordance with table on page 102. 3 4 8. M4 self-tapping screws at nominal 200mm centres. 9. Corner steel angle, 30mm x 30mm x 0.6mm. 8 10. Mineral wool seal. 6 Detail 1 – Cross section through insulated duct. 11. PROMATECT®L500 collar, requirement in accordance with table on page 101. 12. Galvanised C-channel framework, 50mm x 50mm x 2 0.9mm, at board butt joints with cavity void fully infilled with 7 11 mineral wool. 13. Masonry wall or slab. 5 14. M4 self-tapping screws at nominal 200mm centres

or steel strips 63mm x 10mm x 1mm at nominal 4 100mm centres. ➛ 12

NOTE: 1, 2 and 3-sided solutions in combination with walls and ceilings approved, details on request. The above ducts are approved up to 10m in

width. More details of the supporting components are available on request. 2214 10 ➛ 13

Detail 2 – Longitudinal wall penetration.

1 1

8

2114 9

Detail 3 – Edge Fixing. Alternative fixing to steel angles.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

107 SELF-SUPPORTING DUCTS The Fire Protection Handbook

PROMATECT®-L500 Please refer to Design Considerations on page 98 and 99, in The alternative PROMATECT®-L500 self-supporting system conjuction with the guidance given on the pages 110 -111. provides an economical and fire safe method of constructing For selection of board thickness, it will not only depend on the natural and mechanical smoke extract and ventilation ductwork required fire performance but also on the internal cross section without a steel lining. Lengths of the PROMATECT®-L500 of the duct and the operating pressure(s). With large ducts and system are normally prefabricated off-site using medium to high operating pressures, internal stiffeners may be PROMATECT®-L500 boards. This ensures that time spent required (see page 111). on site is kept to a maximum, with little or no disruption to other trades. Tables 1 and 2 below give guidance on these requirements and further assistance is available from the Promat Technical Services Department.

Table 1: Fire Outside (Duct A)

Maximum Fire resistance (minutes) Board Maximum internal Stiffeners duct pressure Stability & Insulation thickness dimensions Method 1 Method 2 (Pa) Integrity (mm) of duct (mm) ± 500 240 120 25 1200 x 1200 ± 500 240 120 25 2000 x 1250 1 row 1 row ± 500 240 120 25 3000 x 1250 2 rows 2 rows ± 750 240 180 40 1200 x 1200 ± 750 240 180 40 2000 x 1250 1 row 1 row 6 ± 750 240 180 40 3000 x 1250 2 row 2 row ± 750 240 180 40 1200 x 1200 ± 750 240 240 52 2000 x 1250 1 row 1 row ± 750 240 240 52 3000 x 1250 2 rows 2 rows + 1000/- 2000 240 180 40 800 x 600 + 1000/- 2000 240 180 40 1440 x 700 1 row + 1000/- 2000 240 180 40 1800 x 600 2 rows + 1000/- 2000 240 180 40 800 x 600 + 1000/- 2000 240 240 52 1440 x 700 1 row + 1000/- 2000 240 240 52 1800 x 600 2 rows

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

108 SELF-SUPPORTING DUCTS The Fire Protection Handbook

Table 2: Fire Inside (Duct B)

Maximum Fire resistance (minutes) Board Maximum internal Stiffeners duct pressure Stability & Insulation thickness dimensions Method 1 Method 2 (Pa) Integrity (mm) of duct (mm) ± 500 240 30 25 1200 x 1200 ± 500 240 30 25 2000 x 1250 1 row 1 row ± 500 240 30 25 3000 x 1250 2 rows 2 rows ± 500 240 30 35 1200 x 1200 ± 500 240 30 35 2000 x 1250 1 row 1 row ± 500 240 30 35 3000 x 1250 2 rows 2 rows ± 750 240 90 40 1200 x 1200 ± 750 240 90 40 2000 x 1250 1 row 1 row ± 750 240 90 40 3000 x 1250 2 rows 2 rows ± 750 240 120 52* 1200 x 1200 ± 750 240 120 52* 2000 x 1250 1 row 1 row ± 750 240 120 52* 3000 x 1250 2 rows 2 rows + 1000/- 2000 240 90 40 800 x 600 + 1000/- 2000 240 90 40 1440 x 700 1 row + 1000/- 2000 240 90 40 1800 x 600 2 rows + 1000/- 2000 240 120 52* 800 x 600 + 1000/- 2000 240 120 52* 1440 x 700 1 row + 1000/- 2000 240 120 52* 1800 x 600 2 rows 6 *To achieve 240 minutes insulation add 50mm mineral wool 100 kg/m3 density. Note: For greater operating pressures and larger ducts please contact Promat Technical Services Department.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

109 SELF-SUPPORTING DUCTS The Fire Protection Handbook

PROMATECT®-L500

TECHNICAL DATA Up to 240 minutes fire rating, stability, integrity and insulation in accordance with the criteria of BS 476: Part 24: 1987. 2 1. PROMATECT®-L500 board, thickness in accordance with 6 Tables 1 and 2 on previous pages. If guidance in Table 1 or 2 requires stiffeners to be used, please refer to details 4 and 5 on the next page. 3 2. SUPALUX® strips, 100mm wide x 9mm thick.

3. VICUBOND WR adhesive in all joints. (PROMASEAL® Sealant may be used on high pressure ducts to seal joints). 4. Steel angle section, 30mm x 30mm x 4mm or similar, at 1 5 maximum 1250mm centres. 5. Threaded steel rod with hexagonal nuts (see below). 4 6. Steel wire staples or deep threaded screws e.g. Buildex HILO, as shown in table below. Board Screws at Staples at 6 thickness (mm) 200mm centres 100mm centres 25 50mm x No.6 63/11/1.5 Detail 3 6 30 63mm x No.8 63/11/1.5 35 63mm x No.8 70/12/2 1 5 40 75mm x No.8 80/12/2 2 52 100mm x No.10 90/12.2/2.3

7. Optional angle trim 4 Detail 1 – Duct support The duct must be supported at maximum 1250mm centres, Detail 1 – Cross section through insulated duct. located to coincide with joints, or to be within 20mm of the joint.

Hangers Each hanger consists of two threaded rods and an angle or 2 1 5 channel section. The hangers may be unprotected provided the rods are not more than 50mm from duct side walls and the stress in the hangers does not exceed the values given in the table below. When hangers exceed 2000mm in length they should be clad with material of similar thickness to the duct to prevent excessive thermal expansion.

When hangers are suspended from protected steel beams it is advisable that the hanger rods should be protected for at least 6 4 300mm from the beams with the same level of protection as the structural beams Detail 2 – Longitudinal section through insulated duct. Vertical duct runs normally require to be tied back to an 6 6 adjoining masonry wall using threaded rods and angle or 3 7 channel support section at maximum 3000mm centres.

3 Fire resistance 1 period (minutes) 30 60 90 120 180 240 Maximum stress (N/mm2) 18 15 10 10 6 6 Detail 3 – Edge fixing. Alternative external angle fixing.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

110 SELF-SUPPORTING DUCTS The Fire Protection Handbook

PROMATECT®-L500

Maximum Duct Size and Opening Pressures 3 The basic duct design shown opposite is adequate for ducts with a maximum internal cross-section of 1200mm x 1200mm for operating pressures up to ± 500 Pa.

This limit can be increased to ± 750 Pa if the board thickness is 40mm or greater. For larger ducts and greater operating 2 pressures, stiffeners are required using either of the methods 1 shown in Details 4 and 5 (also see Tables 1 and 2).

For either method, the minimum stiffener thickness is 40mm. Detail 4 – Stiffener: Method 1.

Detail 4 – Stiffener: Method 1 Stiffeners are constructed with strips of PROMATECT®-L500, 250mm wide, fixed at maximum 600mm centres (Detail 4).

Detail 5 – Stiffener: Method 2 The duct is subdivided by a solid PROMATECT®-L500 board, with holes cut within the wall of a size and quantity to ensure equal crossflow of air between the two halves (Detail 5).

Detail 6 – Masonry wall penetration The duct (1) should pass through the wall opening without 6 interruption. The penetration is sealed with mineral wool of Detail 5 – Stiffener: Method 2. minimum density 60kg/m3 (3). A PROMATECT®-L500 cover angle (2) minimum 80mm x 80mm x 20mm, should be fixed to the duct only, on all four sides. 1 3 4

Insert approximately 30mm of mineral wool (4) between the solid wall and cover angle. For penetrations through lightweight framed partitions, please consult the Promat Technical Services Department.

Detail 7 – Concrete floor penetrations The duct (1) should pass through the floor opening without interruption and the gap is sealed with PROMASEAL® 2 Compound (5). Secure PROMATECT®-L500 reinforcement collars (6) minimum 80mm x 80mm x 20mm to the duct, to transfer the load of duct to the floor. Detail 6 – Masonry wall penetration.

Note: Colllars should be bonded with VICUBOND WR®.

1

6 5 ➛

5

Detail 7 – Concrete floor penetrations.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

111 DURADUCT LT® The Fire Protection Handbook

DURADUCT LT® Construction DURADUCT LT® consists of a galvanised steel inner duct DURADUCT LT® is tried and tested in ductwork solutions for overboarded with 6mm DURASTEEL® and finishing trim natural ventilation ducting, mechanical ventilation ducting, angles. The system is installed using a proprietary flange. natural smoke vents, mechanical smoke vents, fire rated The total thickness of standard DURADUCT LT® is pressurisation ductwork and kitchen extract ducting.

nominally 7.5mm. Performance Up to 240 minutes fire resistance in accordance with the Typical Applications integrity and insulation criteria of BS 476: Part 24:1987. DURADUCT LT® is a fast track and economical DURASTEEL® based fire resisting ductwork solution which combines the airflow and wipe down characteristics of standard galvanised steel ductwork with the armour plated comfort of ‘fit and forget’ DURASTEEL®.

The DURADUCT LT® system is manufactured by approved ductwork contractors and can be delivered to site with minimal site handling. 6

Trim angle ➛ Proprietary flange section ➛

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

112 DURADUCT LT® The Fire Protection Handbook

DURADUCT LT® PROVIDES FOR MODERN FAST TRACK FACTORY FABRICATED ON-SITE INSTALLATIONS

DUCTWORK INSULATION MATRIX - LT®

Applications Powered Ventilation / Natural ventilation / Smoke extraction / Kitchen Extract Notes All ductwork is tested / assessed to BS 476: Part 24: 1987 (ISO 6944 - 1985) Type A duct - Out to In fire condition Type B duct - In to Out fire condition

Additional insulation protection may be required where the duct passes adjacent to combustible materials or hazardous areas. LT standard ductwork is often acceptable in risers and passing through non-combustible areas.

NATURAL VENTILATION

Minutes Stability Integrity Insulation

Type A or B duct - 300ºC To BS 7346 Pt 2: 1990 (to 650ºC) Type A duct - 1000ºC+ Type B duct - 1000ºC+ 30 Yes Yes LT LT LT LT 60 Yes Yes LT LT LT LT + 50mm of 60 kg/m3 120 Yes Yes LT LT LT + 50mm of 60 kg/m3 LT + 80mm of 140 kg/m3 180 Yes Yes LT LT LT + 50mm of 140 kg/m3 LT + 100mm of 140 kg/m3 6 240 Yes Yes LT LT Insulation fails at 220 mins LT + 90mm of 165 kg/m3 LT + 120mm of 140 kg/m3

POWERED VENTILATION / SMOKE EXTRACT

Minutes Stability Integrity Insulation

Type A or B duct - 300ºC To BS 7346 Pt 2: 1990 (to 650ºC) Type A duct - 1000ºC+ Type B duct - 1000ºC+ 30 Yes Yes LT LT LT LT 60 Yes Yes LT LT LT + 30mm of 60 kg/m3 LT + 50mm of 60 kg/m3 120 Yes Yes LT LT LT + 50mm of 60 kg/m3 LT + 80mm of 140 kg/m3 180 Yes Yes LT LT LT + 50mm of 140 kg/m3 LT + 100mm of 140 kg/m3 240 Yes Yes LT LT Insulation fails at 220 mins LT + 90mm of 165 kg/m3 LT + 120mm of 140 kg/m3

KITCHEN EXTRACT Where main fire risk is from in to out - Type B duct, use the above table for powered ventilation / smoke extract Where main fire risk is from out to in - Type A duct at 1000ºC+. Use the table below.

Minutes Stability Integrity Type A duct - 1000ºC+

60 Yes Yes LT + 50mm of 165 kg/m3 120 Yes Yes LT + 90mm of 165 kg/m3

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

113 DURADUCT SMT® FIREBLAST The Fire Protection Handbook

CONSTRUCTION The SMT system is formed by fixing 9.5mm Durasteel® sheets on to a welded or cleated, prefabricated steel skeletal framework, minimum 3mm thick. The sheets are fixed using self-drilling self-tapping screws, with PROMASEAL® sealant applied before fixing to the frame. Flanged lengths of ductwork are bolted together trapping the PROMASEAL® sealant between the mating flanges. The SMT system can be constructed in 1, 2, 3 or 4 sided configurations.

TYPICAL APPLICATIONS DURADUCT SMT® Fireblast has been tested to provide high levels of blast and fire protection making the system uniquely suitable for potentially explosive environments such as electrical transformer and switch gear rooms.

DURADUCT SMT® is also tried and tested in ductwork solutions for smoke control, smoke exhaust, fresh air ventilation, kitchen extraction, fire protection of building 6 services, pressurisation riser shafts, lift-shaft protection and protection of power cables and services.

PERFORMANCE Up to 240 minutes fire resistance in accordance with the integrity and insulation criteria of BS 476: Part 24:1987.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

114 DURADUCT SMT® FIREBLAST The Fire Protection Handbook

DURADUCT SMT® MAY BE CONSTRUCTED IN 1, 2, 3 OR 4 SIDED VERSIONS. THIS VERSATILITY SAVES SPACE, PROGRAMME TIME AND MATERIAL COST

DUCTWORK INSULATION MATRIX – SMT® SYSTEM

Applications Powered Ventilation / Natural ventilation / Smoke extraction / Kitchen Extract 6

Notes All ductwork is tested / assessed to BS 476: Part 24: 1987 (ISO 6944 - 1985) Type A duct - Out to In fire condition Type B duct - In to Out fire condition

Additional insulation protection may be required where the duct passes adjacent to combustible materials or hazardous areas. SMT standard ductwork is often acceptable to Building Control when used in risers and passing through non-combustible areas without additional protection.

NATURAL VENTILATION

Minutes Stability Integrity Insulation

Type A or B duct - 300ºC To BS 7346 Pt 2: 1990 (to 650ºC) Type A duct - 1000ºC+ Type B duct - 1000ºC+ 30 Yes Yes SMT SMT SMT SMT + 50mm of 60 kg/m3 60 Yes Yes SMT SMT SMT SMT + 50mm of 60 kg/m3 120 Yes Yes SMT SMT SMT + 50mm of 60 kg/m3 SMT + 80mm of 140 kg/m3 180 Yes Yes SMT SMT SMT + 50mm of 140 kg/m3 SMT + 100mm of 140 kg/m3 240 Yes Yes SMT SMT Insulation fails at 220 mins SMT + 90mm of 165 kg/m3 SMT + 120mm of 140 kg/m3

POWERED VENTILATION/SMOKE EXTRACT

Minutes Stability Integrity Insulation

Type A or B duct - 300ºC To BS 7346 Pt 2: 1990 (to 650ºC) Type A duct - 1000ºC+ Type B duct - 1000ºC+ 30 Yes Yes SMT SMT SMT SMT + 50mm of 60 kg/m3 60 Yes Yes SMT SMT SMT + 30mm of 60 kg/m3 SMT + 50mm of 60 kg/m3 120 Yes Yes SMT SMT SMT + 50mm of 60 kg/m3 SMT + 80mm of 140 kg/m3 180 Yes Yes SMT SMT SMT + 50mm of 140 kg/m3 SMT + 100mm of 140 kg/m3 240 Yes Yes SMT SMT Insulation fails at 220 mins SMT + 90mm of 165 kg/m3 SMT + 120mm of 140 kg/m3

KITCHEN EXTRACT

Where main fire risk is from in to out - Type B duct, use the above table for powered ventilation / smoke extract Where main fire risk is from out to in - Type A duct at 1000ºC+, use the table below.

Minutes Stability Integrity Type A duct - 1000ºC+

60 Yes Yes LT + 50mm of 165kg/m3 120 Yes Yes LT + 90mm of 165kg/m3

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

115 DURADUCT SR® The Fire Protection Handbook

2 ➛ 3 ➛ ➛ ➛ ➛

7 ➛

6 1 ➛ ➛

6 8

5 4

Duraduct® SR steel run-out ducting – (connected to a Durasteel® smoke extract duct system)

DD/SR 60 – 120 DURADUCT STEEL RUN-OUT TECHNICAL DATA DUCTING 1. Identification labels. A steel duct system tested to BS 476: Part 24: 1987, built to 2. Clamp. enhanced DW144 standards, it provides 60 or 120 minutes 3. Duct support system. stability/integrity. This ducting is for use together with the ® DD/SMT and DD/LT ranges for connection between the 4. DURADUCT steel run-out duct system DD/SR. main smoke extract system and where fire insulation 5. . performance is not required. 6. ‘Knock on flanges’.

Additionally, the system may be used for smaller cross-section 7. Shoe connection. extract ducts that are located within protected shafts. 8. Durasteel DD/SMT or DD/LT. These shafts provide the required fire compartmentation and the aesthetic finishes, such as those often used for toilet PERFORMANCE extract ducting. The DD/SR Range has been tested to: ● BS 476: Part 24: 1987 and meets the fire stability and integrity requirements for up to 120 mins. ● It maintains 75% cross-section and is suitable for smoke extract ducting. ● Air Leakage A -C (DW144).

NOTE: The cross section of the DD/SR duct system is limited to 0.2m2 with no side greater than 0.75 metres wide. Ducts outside this range are manufactured from DURASTEEL®. For full details please contact Promat Technical Services Department.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

116 SELF-SUPPORTING DUCTS The Fire Protection Handbook

SUPALUX® The self-supporting duct system provides an economical and fire safe method of constructing natural and mechanical smoke extract and ventilation ductwork without a steel lining. Lengths of the Promat system can be prefabricated off-site or constructed on site using SUPALUX® boards. This ensures that time spent on site is kept to a minimum, with little or no disruption to other trades.

Please refer to Design Considerations on page 98 and 99, in conjuction with the guidance given on the following pages.

For selection of board thickness, it will not only depend on the required fire performance but also on the internal cross section of the duct and the operating pressure(s). With large ducts and medium to high operating pressures, internal stiffeners may be required.

6

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

117 SELF-SUPPORTING DUCTS The Fire Protection Handbook

TECHNICAL DATA 120 minutes fire rating, stability, integrity and 30 minutes insulation in accordance with the criteria of BS 476: Part 24: 1987.

1. SUPALUX® boards, 20mm thick.

2 2. SUPALUX® strips, 100mm wide x 9mm thick. 3. Corner steel angle, 30mm x 30mm x 1mm thick. 4 4. M4 self-tapping screws at nominal 200mm centres.

5. PROMASEAL® Sealant or VICUBOND® WR at all 1 board joints. 6. Hanger diameter sized to limit stress ≤ 10N/mm2 and 3 minimum 30mm x 30mm x 3mm steel angle depending the size of duct.

6 7. SUPALUX® or PROMATECT®- L500 collar, 150mm wide x 20mm thick.

Installation Method 240 minutes fire rating, stability, integrity and 30 minutes insulation in accordance with the criteria of BS 476: 6 Part 24: 1987. Detail 3 ® 4 1. SUPALUX boards, 25mm thick. 1 2. SUPALUX® strips, 100mm wide x 9mm thick. 6 2 3. Internal steel angle, 30mm x 30mm x 1mm thick, at 3 corners. 4. M4 self-tapping screws at nominal 200mm centres.

5. PROMASEAL® Sealant or VICUBOND® WR at all board joints. Detail 1 – Cross section through insulated duct. 6. Hanger diameter sized to limit stress ≤ 6N/mm2 and minimum 30mm x 30mm x 4mm steel angle depending 10 10 6 2 7 on the size of duct.

➛ ➛ 7. SUPALUX® collar or PROMATECT®- L500, 150mm wide x 20mm thick. 8. Alternative external corner angle, 40mm x 20mm x 0.6mm 3 thick. 9. Steel wire staples, 63mm x 11mm x 2mm, at nominal 150mm centres or M4 self-tapping screws at nominal 200mm centres.

4 10. Steel wire staples, 28mm x 10mm x 1mm, at nominal 150mm centres or M4 self-tapping screws at nominal 200mm centres. Detail 2 – Longitudinal wall penetration. NOTE: SUPALUX® duct systems are approved up to 1000mm wide. For ducts in excess of 1000mm width, please consult Promat Technical Services 3 9 5 8 Department for construction details.

4 4 5

1

Detail 3 – Internal angle fixing. Alternative external angle fixing.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

118 CABLE PROTECTION The Fire Protection Handbook

CABLE PROTECTION DIN 4102: Part 12 assesses the encasement system when In the event of a fire it may be vital to the safety of the building exposed to a fully developed external fire. In addition to the occupants that certain electrical systems and services remain requirement to maintain the integrity of the encasement functioning until all personnel have escaped. Such systems will and any penetrations through walls or floors, the standard therefore require protection from fire for a specified period of requires that: time and may include: (a) The cables continue to function for the duration of the ● Electrically operated fire alarms exposure period; ● Emergency escape route lighting (b) The temperature on the cable jacket should not ● Electrically operated extinguishing systems exceed 150°C. ● Smoke extraction vent systems ● Power supply for fire service elevators in high-rise buildings The tested encasement system protects a wide range of ● Water mains to sprinkler systems different cable types. Power is passed through the cables throughout the test. In addition to protection from fire outside the duct, it is normally vital that any fire within the duct is contained As an added safety factor, the system described in this section e.g. if cable sheathing ignites due to an electrical overload. will ensure that the temperature on the cable jacket does not exceed 120°C. A suitably designed duct will: ● Prevent the propagation of fire from one building DESIGN CONSIDERATIONS compartment to another The following points are some of the factors which should be ● Assist in maintaining escape routes considered when determining the correct specification to ● Ensure the continuing operation of other services within a 6 ensure the cable duct system will provide the required fire common service shaft performance. Further advice can be obtained from the Promat ● Reduce damage to localised areas Technical Services Department. ● Contain smoke and toxic fumes from burning cables 1. Required Fire Exposure BS 6387: 1994 “Specification for performance requirements The specification of a cable duct system will depend on for cables required to maintain circuit integrity under fire whether it is expected to resist external fire, internal fire, conditions”, is often used when considering the suitability of or both. cables for use in protected circuits. Unfortunately, this standard only tests single cables, without any support system, exposed 2. Required Fire Performance to a gas flame. Whilst such a test may be adequate for small Generally, the most onerous requirement is to maintain the cables carefully secured directly to a fire resisting wall or floor, integrity of the circuit(s) when the system is exposed to it is arguable if it is suitable to assess the fire performance of external fire. If this is not needed, the performance larger cables or bunches of cables exposed to a fully requirements may be reduced by the approval authority developed fire on all sides, particularly if they are supported to provide only stability, integrity and insulation of the duct on a suspended cable tray which may be passing through system and/or the wall and floor penetrations. On compartment walls or floors. occasions further relaxations may be approved e.g. a reduced insulation performance can sometimes be The only fire resistance test standards for cable protection acceptable if no combustible materials or personnel systems which simulate a real fire scenario are the German will be in contact with the duct. standards, DIN 4102, “Fire behaviour of building materials and building components”, Parts 11 and 12. 3. Supporting Structure Part 11 assesses the encasement system when exposed to The supporting hangers and their fixings should be capable a fully developed internal fire. The integrity of the encasement, of bearing the load of the complete cable system including and any penetrations through walls and floors, are measured, any applied insulation material or other services suspended plus the temperature on the outer surface of the duct (140°C from it. Chemical anchors are not generally suitable. It is mean rise, 180°C maximum rise). The heating curve for DIN usually not advisable to use unprotected hangers if the 2 4102: Part 11 is the same as that used in BS 476: Part 20: stress exceeds 6N/mm and/or if hanger lengths exceed 1987 and the failure criteria for integrity and insulation are almost 2000mm. The hanger centres should not exceed the identical. The systems detailed are approved for use to provide a distance limits given for the relevant Promat system. performance in accordance with BS 476: Part 20: 1987.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

119 CABLE PROTECTION The Fire Protection Handbook

DESIGN CONSIDERATIONS continued... Table 2: Internal Cross Section 4. Penetrations through Walls & Floors G 110 x 100mm and F 520 x 250mm Lid type Thickness of board for different Care should be taken to ensure that movement of the fire resistance (minutes) Board type cable system in ambient or in fire conditions does not 30 60 90 120 adversely affect the performance of the wall, partition or Loose fit 20mm 40mm 60mm 70mm PROMATECT®-L500 floor or any penetration seal. Fixed 20mm 35mm 50mm 70mm PROMATECT®-L500

5. Other Requirements Acoustic performance, thermal insulation, water FIBRE OPTICS tolerance, strength and appearance can also be important These cables have a lower failure temperature and therefore considerations. the Promat Technical Services Department should be consulted to determine the required board thickness and

Selection of Board Type and Thickness construction details. The Promat systems based on PROMATECT®-L500 or DURASTEEL® would generally be preferred in very onerous INTERNAL FIRE conditions. The board thicknesses given in Tables 3 and 4 will ensure that the stability, integrity and insulation of the duct will be The board thickness will depend on the required fire maintained when exposed to a fully developed cellulosic performance, the internal dimensions of the duct, and whether internal fire (BS 476: Part 20: 1987 curve). or not the duct lid is fixed, as shown in the tables on this page. For ducts which do not require to satisfy the insulation criteria, 6 EXTERNAL FIRE and for larger ducts, please consult the Promat Technical The board thicknesses given in Tables 1 and 2 will ensure Services Department. that when the duct is exposed to a fully developed cellulosic external fire (BS 476: Part 20: 1987 curve), the cable jacket Table 3: For Stability, Integrity in Fire Compartment/ Insulation in Adjacent Compartment temperature rise will not exceed 120°C and the cables will Thickness of board for different Board type remain functioning. If the cables are not required to maintain fire resistance (minutes) circuit integrity it may be possible to reduce the board 30 60 90 120 thickness after consultation with the Promat Technical Services 20mm 30mm 35mm 40mm PROMATECT®-L500 Department. Promat can also advise on specifications for

larger duct sizes. Table 4: For Stability, Integrity & Insulation in Fire Compartment Table 1: Internal Cross Section F 110 x 100mm Thickness of board for different Board type Lid type Thickness of board for different Board type fire resistance (minutes) fire resistance (minutes) 30 60 90 120 30 60 90 120 25mm 35mm 40mm 52mm PROMATECT®-L500 Loose fit 25mm 45mm 60mm 80mm PROMATECT®-L500 Fixed 25mm 40mm 60mm 80mm PROMATECT®-L500

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

120 CABLE PROTECTION The Fire Protection Handbook

EXTERNAL FIRE 10. PROMASEAL® Ventilation Grille or Ventbox to prevent excessive heat build up in duct during non-fire conditions. TECHNICAL DATA Up to 120 minutes fire rating, integrity and insulation in 11. Electrical cables. accordance with the criteria of BS 476: Part 20: 1987. NOTE: Fibre optic cables have a lower failure temperature and therefore the Promat Technical Services Department should be consulted to 1. PROMATECT®-L500 in accordance with determine the required board thickness. Tables 1 or 2 on page 120.

2. PROMATECT®-L500 or SUPALUX® internal strip, 100mm x 20mm thick, located between tray and base of duct only. 9 Strips positioned at maximum 625mm centres and coinciding with board joints and supports (8). 10 3. PROMATECT®-L500 external cover strip to top and side joints only, 100mm x 20mm thick (up to 60 minutes) or 7 100mm x 25mm, (over 60 minutes). These strips are not required for multi-layer constructions providing the joints between the layers are staggered by at least 80mm and fixed to each other.

® 4. PROMATECT -L500 batten, 25mm x 20mm thick, 3 fixed to loose fit lid (not required for fixed lid option). 8 5. At wall penetrations, seal gaps up to 20mm wide with 11 1 mineral wool and PROMASEAL® Sealant. For gaps greater 6 6 2 than 20mm fix a PROMATECT®-L500 collar on both sides of the wall, minimum collar dimensions 150mm x 20mm External Fire thick. 4 1 3 9 6. Steel cable tray (always required for external fire exposure). 7 7. Fixing options as below. Screws should be deep-threaded, self-tapping, type e.g. Buildex HILO. 6 Alternatively, steel staples can be used. 11 2 Board thickness Screws at Staples at 8 (mm) 200mm centres 100mm centres Detail 1 – Cross section through duct. 20 38mm x No.6 50/11/1.5 25 50mm x No.6 63/11/1.5 3 1 4 7 9 30 63mm x No.8 63/11/1.5 35 63mm x No.8 70/12/2 6 40 75mm x No.8 80/12/2 50 100mm x No.10 80/12/2 11 60 100mm x No.10 90/12/2 70 Multi-layer Fix layer 1 with screws 2 8 80 Multi-layer Fix layer 1 with screws Detail 2 – Longitudinal section through duct. 8. Support angle or channel, size will depend on load Maximum permissible bending stress 6N/mm2. Supports should be at maximum 1250mm centres 1 7 5

and should coincide with an internal cover strip (2). 6 The cable duct should be supported not more than 500mm from either side of the wall. 11 9. Threaded steel hanger rod, minimum diameter 8mm at maximum 1250mm centres, ensure maximum stress does not exceed 6N/mm2. 2

Detail 3 – Wall penetration.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

121 CABLE PROTECTION The Fire Protection Handbook

INTERNAL FIRE 2. PROMATECT®-L500 or SUPALUX® internal strip, 100mm x 20mm thick, located between tray and base of duct only. TECHNICAL DATA Strips positioned at maximum 625mm centres and Up to 120 minutes fire rating, integrity and insulation in coinciding with board joints and supports (8). accordance with the criteria of BS 476: Part 20: 1987. 3. SUPALUX® external cover strips, 100mm x 9mm thick, to 1. PROMATECT®-L500 in accordance with Tables 3 or 4 top and side joints only. For ducts with an internal height on page 120. greater than 300mm replace the external strip with an

® 9 internal SUPALUX strip, 100mm x 15mm thick. Fix side boards to ends of internal strip to strengthen casing, external trips not required for multi-layer construction 10 providing the joints between layers are staggered by at least 80mm and fixed to each other. 7 4. PROMATECT®-L500 or SUPALUX® batten, 25mm x 20mm thick, fixed to loose fit lid (not required for fixed lid option). 5. At wall penetrations, seal gaps up to 20mm wide with mineral wool and PROMASEAL® Sealant. For gaps greater 3 than 20mm fix a PROMATECT®-L500 or SUPALUX® collar on both sides of the wall, minimum collar dimensions 11 1 8 150mm x 20mm thick. 2 6. Steel cable tray (not required for internal fire exposure 6 unless the cable weight exceeds 25 kg/m, then a cable Internal Fire tray should be used or the hanger centres should 4 be reduced). 1 3 9 7. Fixing options as below. Screws should be deep-threaded, 7 self-tapping, drywall type e.g. Buildex HILO. 6 Alternatively, steel staples can be used. 11 2 Board thickness Screws at Staples at (mm) 200mm centres 100mm centres 8 9 25mm x No.6 28/10/1.2 Detail 1 – Cross section through duct. 15 30mm x No.6 32/10/1.2 20 38mm x No.6 50/11/1.5 25 50mm x No.6 63/11/1.5 3 1 4 7 9 30 63mm x No.8 63/11/1.5 35 63mm x No.8 70/12/2 6 40 75mm x No.8 80/12/2 50 100mm x No.10 80/12/2 11 60 100mm x No.10 90/12/2 70 Multi-layer Fix layer 1 with screws

2 8 8. Support angle or channel, size will depend on load Detail 2 – Longitudinal section through duct. Maximum permissible bending stress 6N/mm2. Supports should be at maximum 1250mm centres and should coincide with an internal cover strip (2). 1 7 5 The cable duct should be supported not more than 500mm from either side of the wall. 9. Threaded steel hanger rod, minimum diameter 8mm at maximum 1250mm centres, ensure maximum stress 11 does not exceed 6N/mm2.

10. PROMASEAL® Ventilation Grille or Promat Ventbox to prevent excessive heat build up in duct during non-fire 2 conditions. Detail 3 – Wall penetration. 11. Electrical cables.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

122 CABLE PROTECTION – EXTERNAL OR INTERNAL FIRES The Fire Protection Handbook

ACCESS HATCHES AND VENTILATION OPENINGS For the installation and inspection of cables, a loose lid construction may be employed as described on pages 121 or 122. Alternatively, the lid can be fixed and inspection openings with hatches can be provided in the side walls of the duct as shown.

TECHNICAL DATA Up to 120 minutes fire rating, integrity and insulation in accordance with the criteria of BS 476: Part 20: 1987. 1 3

® 1. PROMATECT -L500 system encasing cable run. 2 Construction of inspection opening. 2. PROMATECT®-L500 inspection hatch comprising: a) Inner board stapled or secured to outer board. The inner board should be a close fit in the opening and 5 6 should be the same thickness as the wall of the duct. b) Outer board, at least 20mm thick, overlapping duct walls by at least 50mm. 4 7 3. Secure complete hatch to duct using threaded inserts e.g. Tecserts (Armstrong Fastening Systems) at maximum Multiple cable outlet exit from duct. 200mm centres. 9 6 4. Electric cables.

5. Wall of PROMATECT®-L500 system.

6. PROMATECT®-L500, at least 50mm wide x 20mm thick, secured to main panels using fixings given in the tables on pages 121 or 122.

7. Seal gaps for full depth of board thickness with 8 PROMASEAL® Sealant.

Ventilation for the cables can be provided by either or PROMASEAL® Ventilation Grille (8) or Promat Ventbox (9). PROMASEAL® Ventilation Grille and Promat Ventbox.

Detail 1 – Section through PROMASEAL® Ventilation Grille 8 10 ● Standard Grille size is 93mm x 93mm overall. Can be combined as multiples to create a larger free area ● Open area per Grille = 0.0035m2. 11 ● Grilles supplied in various thicknesses as follows: 35mm (30 minutes), 60mm or 2 x 35mm (60 minutes), Detail 1 – Section through PROMASEAL® Ventilation Grille. 75mm (120 minutes) and 75 + 35mm (240 minutes). ● Friction fit Grille (8) in aperture. Use VICUBOND® WR 13 adhesive if loose fit. ● Secure 50mm wide cover strips (10) if necessary to 12 ensure Grille fully surrounded by board. ● The Grille is supported on the inside of the duct by a perforated steel plate (supplied) (11) secured to the duct wall. Detail 2 – Section through Promat Ventbox. Detail 2 – Section through Promat Ventbox ● The Ventbox consists of an integral outer frame and collar ● Outer dimensions of frame and collar are (12) and an automatically operated closing lid (13) which is 515mm x 130mm. activated by a thermal link in the event of a fire. ● Insert Ventbox frame into aperture, 465mm x 80mm, and ● Free area 0.021m2. screw down to the board through the collars.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

123 MECHANICAL & ELECTRICAL SERVICES ENCLOSURES The Fire Protection Handbook

DESIGNER SELECTOR TABLE

Mechanical & Electrical Services Enclosures Integrity & Insulation Product Fire Rating Collar Size Mineral Wool Stability/ Integrity/ Insulation VICUCLAD® or VICUTUBE® ● 30mm thick 60/60/60 80mm x 30mm thick 25mm x 72 kg/m3 ● 40mm thick 120/120/120 80mm x 40mm thick 40mm x 80 kg/m3 ● 70mm thick 240/240/240 80mm x 70mm thick 60mm x 80 kg/m3

SUPALUX® ● 20mm thick 60/60/60 100mm x 9mm thick 50mm x 60 kg/m3 ● 50mm thick 120/120/120 100mm x 15mm thick 50mm x 80 kg/m3 ● 50mm thick 240/240/240 100mm x 20mm thick 100mm x 100 kg/m3

PROMATECT®-L500 ● 20mm thick 120/120/120 100mm x 9mm thick 50mm x 100 kg/m3 (SUPALUX®) ● 50mm thick 120/120/120 100mm x 9mm thick Not required (SUPALUX®) 6 ● 50mm thick 240/240/240 100mm x 9mm thick 50mm x 80 kg/m3 (SUPALUX®) DURASTEEL® ● 6mm thick 120/120/120 100mm x 6mm thick 80mm x 140 kg/m3 ● 9.5mm thick 240/240/240 100mm x 9.5mm thick 140mm x 140 kg/m3

Mechanical & Electrical Services Enclosures Integrity & Insulation Product Fire Rating Collar Size Mineral Wool Stability/ Integrity/ Insulation SUPALUX® ● 9mm thick 120/120/- 100mm x 9mm thick Not required ● 12mm thick 240/240/- 100mm x 12mm thick Not required

PROMATECT®-L500 ● 25mm thick 120/120/30 100mm x 9mm thick Not required (SUPALUX®) ● 50mm thick 240/240/120 100mm x 12mm thick Not required (SUPALUX®)

DURASTEEL® ● 6mm thick 120/120/- 100mm x 6mm thick Not required ● 9.5mm thick 360/360/- 100mm x 9.5mm thick Not required

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

124 MECHANICAL & ELECTRICAL SERVICES ENCLOSURES The Fire Protection Handbook

INTEGRITY & INSULATION TECHNICAL DATA 60 to 240 minutes fire rating, integrity and insulation in 6 5 accordance with the criteria of BS 476: Part 20: 1987 internal or external fire. 2 1 1. VICUCLAD®, PROMATECT® -L500 or SUPALUX® boards, thickness in accordance with table on page 124.

2. SUPALUX® strips, 100mm wide x 9mm thick, where applicable.

3. VICUCLAD®, PROMATECT® -L500 or SUPALUX® collar, 7 size in accordance with table on page 124. 4. Steel channel collar, minimum 50mm x 50mm x 0.9mm thick, at butt joints of nominal 1220mm centres. 9 4 5. M4 self-tapping screws at nominal 200mm centres. 10 6. For 120 minutes fire rating: Threaded rod hanger stress not to exceed 10N/mm2.

For 240 minutes fire rating: Installation Method Threaded rod hanger stress not to exceed 6N/mm2. 10 4 6 7. 1, 2 or 3-sided construction: 6 (≤ 120 minutes fire rating) 7 Steel angle, minimum 50mm x 50mm x 0.9mm thick. 1 (≤ 240 minutes fire rating) Steel angle, minimum 50mm x 50mm x 3mm thick. 2 9 4-sided construction: 5 Steel angle, minimum 30mm x 30mm x 0.5mm. 8. M4 self-tapping screws at nominal 200mm centres or steel staples, at nominal 100mm centres. Detail 1 – Cross section through duct. 9. General E & M services e.g. cable trunking and steel pipes, etc. 2 1 6 3 10. Mineral wool, requirement in accordance with table on page 124. 11. Cantilever arm at maximum 1250mm centres.

NOTE: Solutions for the construction of systems with 1, 2 and 3-side used in combination with walls and ceilings are approved, details on request.

The above details are applicable for enclosures not exceeding 1220mm wide,

® PROMATECT enclosures for M & E services are approved for widths up to 4 9 5 6m, please consult Promat Technical Services Department for details.

The above specifications are applicable for providing a fire resistance level in accordance with the integrity and insulation requirements of BS 476: Part 20 and relate to compartmentation. The constructions as detailed above do not Detail 2 – Longitudinal section through duct. necessarily provide sufficient insulation performances to ensure that the services contained therein will continue to function under fire conditions. 7 8 1 If in doubt, please contact Promat Technical Services Department. 1

5

Detail 3 – Fixing to steel angle. Alternative board to board edge fixing.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

125 MECHANICAL & ELECTRICAL SERVICES ENCLOSURES The Fire Protection Handbook

6

9 1 2 10 4

4

7

9 5 1 2 10 7 5

11 Detail 4 – 1-sided enclosure.

6

6 7 9 4 Detail 7 – 3-sided enclosure (case 2).

5

1 2 10

Detail 5 – 2-sided enclosure.

6

1 7 6 2 9 7 9 5 4

10 4 5

1 2 10

Detail 6 – 3-sided enclosure (case 1). Detail 8 – 4-sided enclosure.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

126 MECHANICAL & ELECTRICAL SERVICES ENCLOSURES The Fire Protection Handbook

INTEGRITY ONLY For the provision of fire resisting constructions to cable ducts and general building services in accordance with the 4 performance criteria of BS 476: Part 20: 1987. No specific 1 British Standard exists for integrity only performance to cable 5 ducts. Therefore for the provision of fire resisting constructions to cable ducts and general building services, Promat constructions have been tested in accordance with the criteria of German DIN 4102, or British Standard BS 476: Part 20: 1987, and assessed to the criteria of BS 476: Part 24: 1987. 6 The assessments include allowance for both internal and external fire. The integrity and, where pertinent, the insulation performance of the enclosure, and any penetrations through compartment walls and floors, are measured. 2 3 Circuit integrity of electrical cables, or ability of the services to function, are not measured and do not constitute part of the Installation Method 1 failure criteria. Where circuit integrity of electrical cables are required, please refer to the Electrical Cable section of this chapter. For the provision of a protection system which will ensure the ability of any other services to function unimpaired 4 in case of fire, e.g. fuel pipes, water mains, please consult the 1 6 Promat Technical Services Department. 5

TECHNICAL DATA 120 minutes fire rating, integrity in accordance with the criteria of BS 476: Part 20: 1987; internal or external fire.

1. Fire protection boards, thickness in accordance with table 6 on page 124. 2. Steel channel collar, minimum 50mm x 25mm x 0.5mm thick, at butt joints of nominal 1220mm centres. 2 3 3. M & E services e.g. cable trunking and steel pipes, etc. Installation Method 2 4. Hanger diameter sized to limit stress not to exceed 10N/mm2. 5 5 2 5. M4 self-tapping screws at nominal 200mm centres. 1 1 6. Steel angle, minimum 30mm x 30mm x 0.5mm thick, at corners.

6 6 240 minutes fire rating, integrity in accordance with the criteria of BS 476: Part 20: 1987; internal or external fire. Detail 1 – Fixing to steel angle. Detail 2 – Butt joint detail. 1. Fire protection boards, thickness in accordance with table 6. Steel angle minimum, 30mm x 30mm x 0.5mm thick, at on page 124. corners. 2. Steel channel collar, minimum 50mm x 25mm x 0.5mm NOTE: Solutions for the construction of systems with 1, 2 and 3-side used in thick at butt joints of nominal 1220mm centres. combination with walls and ceilings are approved, details on request. (2) 3. M & E services e.g. cable trunking and steel pipes, etc. For enclosure with a width exceeding 1220mm, the steel channel collar shall be spaced at centres such to ensure a maximum unsupported area not 4. Hanger diameter sized to limit stress not to exceed exceeding 1.5m2. The maximum approved width of the construction detail is 6N/mm2. 6000mm. 5. M4 self-tapping screws at nominal 200mm centres. If the M & E service (3) being encased is a plastic pipe, external hangers and angles with stress F 10N/mm2 will be required to independently support the enclosure.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK

127 MECHANICAL & ELECTRICAL SERVICES ENCLOSURES The Fire Protection Handbook

DURASTEEL® 6 DURASTEEL® enclosures provide protection against fire to

➛ cable ducts and general building services in accordance with 2

the relevant criteria of BS 476: Parts 20: 1987 and 22: 1987.

➛ 1 ® ➛ DURASTEEL systems are suitable for providing protection to services even under extremely aggressive environments.

The DURASTEEL® systems described below ensure the integrity of fire compartments. If the services are required to continue functioning in the event of fire, please consult the

Promat Technical Services Department. ➛

➛ 5

➛ The maximum permissible dimensions for enclosures are 7 ➛ 3 up to 3000mm x 1500mm for up to 240 minutes fire 4 resistance. For hanger sizes please consult Promat Technical Services Department.

TECHNICAL DATA 1. DURASTEEL® boards, thickness in accordance with table on page 124.

6 2. Steel flanges, fabricated by cutting and welding 50mm x 50mm x 3mm thick angles, are bolted together with M8 nuts and bolts at nominal 250mm centres to form continuous sections.

3. Cable tray or services enclosure.

4. Corner steel angle reinforcement, 50mm x 50mm x 3mm thick, these corner angles do not require any mechanical fixing to the flanges (2).

5. Support channels, sized according to duct weight, size and required fire resistance.

6. Steel hanger rods, sized according to duct weight, size and required fire resistance.

7. Cables or services.

THE PASSIVE FIRE PROTECTION HANDBOOK PROMAT UK LIMITED

128 Backcover.qxd 7/11/03 11:02 am Page 179

CONTACT NUMBERS The Fire Protection Handbook

PROMAT TECHNICAL SERVICES DEPARTMENT Telephone: 01344 381400 Fax: 01344 381401 Email: [email protected]

PROMAT MARKETING SERVICES DEPARTMENT Telephone: 01344 381350 Fax: 01344 381401 Email: [email protected]

PROMAT CUSTOMER SERVICES DEPARTMENT Telephone: 01344 381381 Fax: 01344 381380 Email: [email protected]

PLEASE NOTE: Every care has been taken to ensure that the contents of this Handbook are accurate, however, Promat UK Limited and its subsidiary companies cannot accept any responsibility for omissions, errors or for information which is found to be misleading. Some of the specifications used in this Handbook may not be complete and may not give full fixing details and it is your responsibility to satisfy yourself of the suitability of any specifications mentioned to meet your requirements. If further assistance is required please contact Promat Technical Services Department. In all cases all current building regulations and approved documents and local fire authorities and insurers must be consulted as appropriate.

The information and recommendations contained in this Handbook are based upon the best knowledge available at the time of publication. Promat UK Limited reserve the right to alter products and specifications without notice.

Produced and typeset at Promat UK Limited.

PROMAT UK LIMITED THE PASSIVE FIRE PROTECTION HANDBOOK Backcover.qxd 7/11/03 11:02 am Page 180

The Fire Protection Handbook

PROMAT UK LIMITED The Sterling Centre, Eastern Road, Bracknell, Berkshire RG12 2TD Telephone: 01344 381300 Fax: 01344 381301 www.promat.co.uk