LSASDPROC-1011-R2.0 Equipment Certification Effective Date: August 16, 2019 Region 4 U.S. Environmental Protection Agency Laboratory Services and Applied Science Division Athens, Georgia Operating Procedure Title: Equipment Certifications ID: LSASDPROC-1011-R2.0 Issuing Authority: Deputy Director, LSASD Effective Date: August 16, 2019 Review Due Date: August 16, 2023 Purpose This Operating Procedure is specific to the Region 4 Laboratory Services and Applied Science Division to maintain conformance to technical and quality system requirements. Properly functioning support equipment is an essential component of producing accurate test results. As such, a regular schedule for verifying the accuracy of support equipment is necessary. The purpose of this procedure is to ensure that all support equipment (temperature sensors, barometers, balances, weights, pH meters, pipets and diluters) utilized by field investigators and laboratory analysts are properly certified and provide the appropriate level of traceability. Scope/Application The requirements of this procedure apply to all personnel who perform work under the LSASD Quality Management System (QMS). Section 6.5.2 of the ISO/IEC International Standard 17025/2017 requires establishment of traceability for measurement standards and measuring instruments to the International System of Units (SI) by means of calibrations or comparisons linking them to relevant primary standards of the SI units of measurement. All equipment used for obtaining measurements within the LSASD Quality System will be certified on the schedules detailed in this operating procedure. While this SOP may be informative, it is not intended for and may not be directly applicable to operations in other organizations. Mention of trade names or commercial products in this operating procedure does not constitute endorsement or recommendation for use. Page 1 of 17 LSASDPROC-1011-R2.0 Equipment Certification Effective Date: August 16, 2019 TABLE OF CONTENTS 1.0 Procedure ........................................................................................................ 3 1.1 Certification of Temperature Sensors .............................................................. 3 1.1.1 Certification of the Mettler T90 Temperature Sensor ................................. 5 1.1.2 Certification of Programmable HotBlock Temperature Sensors ........... 6 1.1.3 Certification of the Nippon RA4500 Internal Temperature Sensor .......... 7 1.2 Certification of Barometers .............................................................................. 7 1.3 Certification of Laboratory Balances and Balance Checks ........................... 8 1.4 Certification of Laboratory Weights ................................................................ 9 1.5 Certification of Laboratory Pipettes .............................................................. 10 1.6 Certification of Automated Diluters (i.e. Digiflex®) ..................................... 12 1.7 Certification of pH Meters .............................................................................. 13 2.0 Definitions...................................................................................................... 13 3.0 References ...................................................................................................... 13 4.0 Revision History ............................................................................................ 14 Attachment 1 ............................................................................................................ 15 Acceptance Limits for Analytical Balance Checks ............................................... 15 Attachment 2 ............................................................................................................ 16 Acceptance Limits for Top Loader Balance Checks ............................................ 16 Attachment 3 ............................................................................................................ 17 LSASD Balance Check Logbook Form ................................................................. 17 Page 2 of 17 LSASDPROC-1011-R2.0 Equipment Certification Effective Date: August 16, 2019 1.0 Procedure 1.1 Certification of Temperature Sensors Certification of temperature measuring devices is accomplished by comparing temperature readings from working temperature sensors to a reference standard that has an independent certification of accuracy traceable to the National Institute of Standards and Testing (NIST). The Laboratory Quality Manager (LQM) will maintain certified reference thermometers and thermocouples to be used exclusively for this purpose. Each temperature sensor utilized in LSASD’s quality system will be certified annually against a certified reference standard. The reference standard being utilized for the certification must be capable of achieving the appropriate level of uncertainty for the intended use of the sensor being certified. Any applications requiring a temperature control tighter than + 1 ºC will be identified and information relayed to the LQM by the Section Chiefs. The equipment will also be labelled with the certification requirements for the temperature measuring devices. It is the responsibility of the staff member performing the certification to verify that the reference standard being utilized for certification meets the accuracy and precision limits required for the device under certification. Thermometers or thermocouples used in refrigerators, freezers, ovens, water baths, hot blocks, etc., should be verified at the working temperature or within the working range. The LQM will be responsible for facilitating the certification of all temperature devices within the laboratory areas. The LQM must be notified of new equipment purchases that include temperature measuring devices so that the equipment can be certified at the correct interval and accounted for within the equipment inventory. The LQM maintains all certification records. The LQM will also maintain an inventory of all thermometers and their certification schedules and make it available for review on the LAN. The following details the certification procedures for each type of temperature sensor in use at LSASD. 1. Thermometers and Thermocouples operating in refrigerators, freezers, ovens, water baths, and hot blocks – Place the working and reference temperature sensor side by side within the area the readings will be recorded. Care should be taken to prevent the two sensors from touching. Note: If an ethylene glycol bottle sensor is utilized, both devices should be placed inside the liquid solution. Allow the working and reference devices to stabilize for a minimum of 15 minutes (for devices utilized in freezers, a minimum of one hour should be allowed for proper equilibration). Record the temperature from each device on the LSASB Thermometer Certification Form. The difference between the two devices should be ≤1°C. 2. Thermometers and Thermocouples operating below room temperature – Prepare an ice bath using crushed ice and distilled water. This bath must have a complete mix of ice/water slurry within the entire container. This mix should be prepared within a 500 mL beaker or larger. Allow the Page 3 of 17 LSASDPROC-1011-R2.0 Equipment Certification Effective Date: August 16, 2019 ice/water mix to stand for 10 minutes and then place the thermometers side by side within the mixture. Allow the working and reference devices to equilibrate for a minimum of 15 minutes. Read the temperature from each device and record it onto the LSASB Thermometer Certification Form. The difference between the two devices should be ≤1°C. 3. High Temperature Thermocouples and Digestion Blocks – High temperature applications (>100 °C) such as ovens, muffle furnaces and TKN digestion blocks are verified against a reference thermometer. Fill a beaker or digestion tube with sand and insert the reference standard (thermocouple) in the sand. Place the beaker or digestion tube in the device (muffle furnace, digestion block, etc), ramp the temperature to the maximum temperature prescribed by the method and allow to equilibrate for a minimum of 15 minutes after the set temperature has been achieved. Record the temperature from the thermocouple on the LSASB Thermometer Certification Form along with all other required information. The difference between the two devices should be: i. ≤2°C for temperatures >100°C, but <180°C ii. ≤50°C for temperatures >180°C, but <550°C iii. ≤50°C for temperatures >550°C If differing criteria are specified in the method, method -specified criteria will be observed. 4. Thermometers and Thermocouples operating at or above room temperature – Note: Thermometers that are not assigned a specific use or are not clearly labeled as to the specific working range will be certified by this procedure. Set a constant temperature water bath or drying oven at approximately 75 ºC and allow the temperature to stabilize. Place the working thermometer next to the reference thermometer in the water bath and let stabilize for approximately 15 minutes. Record the temperature from each device onto the LSASB Thermometer Certification Form along with all other required information. The difference between the two devices should be ≤1°C. For field thermometers with both a probe and internal sensor (Indoor and Outdoor displayed values), both sensors will be certified. The probe will be certified as detailed above. The internal sensor will be certified against a second reference thermometer at