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Fibreboards — Specifications — Part 1: General Requirements

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Fibreboards — Specifications — Part 1: General Requirements ` KENYA STANDARD DKS 2706-1: 2016 Fibreboards — Specifications — Part 1: General requirements COMMITTEE DRAFT 2016 © KEBS 201 6 First Edition 2016 ©KEBS 2016 — All rights reserved 1 DKS 2706 - 1: 2016 TECHNICAL COMMITTEE REPRESENTATION The following organizations were represented on the Technical Committee: 1. Elle Interior Designers Ltd 2. Kenya Industrial Research And Development Institute (KIRDI) 3. University of Nairobi 4. Consumer information network 5. Global Hardware limited 6. PG Bison 7. Timsales Limited 8. University of Eldoret 9. KEFRI 10. Kenya Wood Preservation Association 11. Alogo Enterprises 12. Kenya Bureau of Standards — Secretariat REVISION OF KENYA STANDARDS In order to keep abreast of progress in industry, Kenya Standards shall be regularly reviewed. Suggestions for improvements to published standards, addressed to the Managing Director, Kenya Bureau of Standards, are welcome. © Kenya Bureau of Standards, 2016 Copyright. Users are reminded that by virtue of Section 25 of the Copyright Act, Cap. 12 of 2001 of the Laws of Kenya, copyright subsists in all Kenya Standards and except as provided under Section 26 of this Act, no Kenya Standard produced by Kenya Bureau of Standards may be reproduced, stored in a retrieval system in any form or transmitted by any means without prior permission in writing from the Managing Director. Fibreboards — Specifications — Part 1: General requirements KENYA BUREAU OF STANDARDS (KEBS) Head Office: P.O. Box 54974, Nairobi-00200, Tel.: (+254 020) 605490, 602350, Fax: (+254 020) 604031 E-Mail: [email protected], Web:http://www.kebs.org Coast Region L a k e R e g i o n R i f t V a l l e y R e g i o n P.O. Box 99376, Mombasa-80100 P.O. Box 2949, Kisumu-40100 P.O. Box 2138, Nakuru-20100 T e l . : ( + 2 5 4 0 4 1 ) 2 2 9 5 6 3 , 2 3 0 9 3 9 / 4 0 T e l . : ( + 2 5 4 0 5 7 ) 2 3 5 4 9 , 2 2 3 9 6 T e l . : ( + 2 5 4 0 5 1 ) 2 1 0 5 5 3 , 2 1 0 5 5 5 F a x : ( + 2 5 4 0 4 1 ) 2 2 9 4 4 8 Fax: (+254 057) 21814 ©KEBS 2016 — All rights reserved 3 DKS 2706 - 1: 2016 Foreword This Kenya Standard was prepared by the Plywood and Boards Technical Committee under the guidance of the Standards Projects Committee and it is in accordance with the procedures of the Kenya Bureau of Standards. Medium density fibre board is a panel product manufactured from lignocellulosic fibres combined with synthetic resin or other suitable binder. The panels are manufactured to a specific gravity of 0.6 to 0.9 by the application of heat and pressure by a process in which the interfibre bond is substantially created by the added binder. Other materials may have been added during manufacturing to improve certain properties. In formulation of this standard, due weightage has been given to standards and practices prevailing in different countries and also to the climatic conditions and customs in the country. In this revision properties have been incorporated to facilitate the proper application of product, properties like modulus of elasticity and the values indicating minimum and average have been included. KENYA STANDARD 1. Scope This Kenyan Standard specifies the requirements for some properties which are common to all uncoated fiberboard types 2. Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. Information on currently valid national and international standards can be obtained from the Kenya Bureau of Standards. EN 120, Wood-based panels — Determination of formaldehyde content — Extraction method called the perforator method. EN 316, Wood fibreboards — Definition, classification and symbols. EN 322, Wood-based panels — Determination of moisture content. EN 323, Wood-based panels — Determination of density. EN 324-1, Wood-based panels — Determination of dimensions of boards — Part 1: Determination of thickness width and length. EN 324-2, Wood-based panels — Determination of dimensions of boards — Part 2: Determination of squareness and edge straightness. EN 326-2, Wood-based panels — Sampling, cutting and inspection — Part 2: Quality control in the factory. EN 326-3, Wood-based panels — Sampling, cutting and inspection — Part 3: Inspection of a consignment of panels. EN 622-2, Fibreboards — Specifications — Part 2: Requirements for hardboards. EN 622-3, Fibreboards — Specifications — Part 3: Requirements for medium boards. EN 622-4, Fibreboards — Specifications — Part 4: Requirements for softboards. EN 622-5, Fibreboards — Specifications — Part 5: Requirements for dry process boards (MDF). ENV 717-1, Wood-based panels — Determination of formaldehyde release — Part 1: Formaldehyde emission by the chamber method. EN 717-2, Wood-based panels — Determination of formaldehyde release — Part 2: Formaldehyde release by the gas analysis method. 3. Requirements Fibreboards shall comply with the general requirements listed in Table 1 and the thickness tolerances listed in Table 2 when dispatched from the producing factory. For certain uses of fibreboards (see specific standards for fibreboards types and general performance standards for wood-based panels), in the case of dispatch in cut sizes, or when further machined (e.g. tongued ad grooved), special tolerances for nominal dimensions, squareness and edge straightness may be agreed upon. The values given in Table 1 and Table 2 for tolerances for nominal dimensions (thickness, width and length), squareness, edge straightness and density within a panel, are characterized by a moisture content in the material corresponding to a temperature of 20 C and a relative humidity of 65 %. Properties not required for specific board types are marked “—“. The requirements relating to formaldehyde potential (perforator value) shall be met by the 95 percentile value based on test values of individual boards. The 95 percentile value shall be equal to or less than the value given in Table 1. Table 1 — General requirements for different types of fibreboard at dispatch ©KEBS 2016 — All rights reserved 5 DKS 2706 - 1: 2016 Table 2 — Tolerances on nominal thickness for fibreboards at dispatch 3.1. Terms and definitions 4. Verification of compliance 4.1. General Verification of compliance with this European Standard shall be carried out using the test methods listed in Table 1. 4.2. External control External control of the factory, if any, shall be carried out according to EN 326-2. The inspection of a consignment of panels shall be carried out according to EN 326-3. In the case of formaldehyde potential determined by EN 120 perforator method, however, for both external control and inspection of a consignment of panels, the respective requirements set out in Table 1 shall be the arithmetic mean value of at least three boards. Additionally, no individual board shall exceed an upper tolerance limit of + 10 %. 4.3. Factory production control Factory production control shall be carried out according to EN 326-2. The properties listed in Tables 1 and 2 shall be controlled, using intervals between tests not exceeding those given in Table 3. Sampling shall be carried out at random. Alternative test methods and/or unconditioned test pieces may be used if a valid correlation to the specified test methods can be proven. The intervals between tests given in Table 3 are related to a production under statistical control. Table 3 — Maximum intervals between tests for each production line 5. Marking Marking of fibreboards shall be carried out in accordance with EN 622-2, EN 622-3, EN 622-4 and EN 622-5 as appropriate. Colour coding is voluntary. If applied, it shall comply with the system shown in annex A. This standard does not exclude colour dyeing of the whole board or individual layers of the board according to traditional national practices. ©KEBS 2016 — All rights reserved 7 DKS 2706 - 1: 2016 Annex A (Normative) Voluntary colour coding system for fibreboards Two colours are used in each case. The first colour defines the panel as either intended for general purposes use or for load-bearing applications (either one or two stripes of this colour are used). The second colour identifies the panel as being suitable for use either in dry or in humid or in exterior conditions. The colours used are as follows: F i r s t c o l o u r w h i t e g eneral purpose First colour yellow load-bearing Second colour blue dry conditions Second colour green humid conditions Second colour brown exterior conditions. .
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