National Laboratory Association Test and Measurements 31 July – 1 August 2017

National Laboratory Association 31 July -1 August 2017 Interlaboratory Comparison of Stack Particulate Matter Measurements National Laboratory Association 31 July -1 August 2017

Scope: Participation Criteria This procedure is relevant to key network personnel directly associated with compliance to the ISO 17025 for stack testing Where two or more participating test measuring teams, use there own equipment and personnel to implement iso kinetic dust sampling on the same stack at the same time The purpose of the ILC testing is to evaluate the technical ability of the laboratory, using the same sample matrix and appropriate sample designs Use of USEPA method 5 or 17, for this presentation method 17 will be used as reference

Introduction This procedure is used to ensure that all the Stack Testing teams operate in accordance with ISO 17025 requirements, providing reliable iso kinetic dust emission results. This interlaboratory comparison has not yet been implemented, in South Africa at any site by any stack testing team. It is hoped that by using this procedure it will provide a bench mark to start such a comparison activity. After implementing the procedure it is possible that changes will have to be made to ensure its practical use It will be a requirement for all stack testing laboratories that carry out compliance sampling for the authorities to have ISO17025 accreditation by 2018, reference document SANAS R80-02

Preparation A presite visit should be done to ensure the suitability of the sampling site, access to points, availability of power supply, sample ports large enough for lances. Ensure that testing teams have completed their safety induction training and medical surveillance as would be required by the plant on which the testing will take place. Ensure online dust emission analyser has been calibrated, using IKS , these results will be the reference data for comparison of ILC testing between laboratories Determine what type of filter will be used either Glass fibre or Quartz fibre Sample filters to be prepared by a single laboratory for both testing teams. Before starting test run determine operation conditions of plant

Required Equipment Sampling train, with connection for nozzle, filter housing Suction tubing between sample probe and control unit Condenser for moisture capture Flow regulating valve Vacuum pump Rotameter Gas analysers to determine oxygen concentration of stack gas Log sheet to record test run readings

Measurement Protocol Hoist sampling equipment up to platform from which the sample ports to the stack can be accessed Prepare sampling train and ensure suitable power supply Remove blank plates from sample ports, verify direction of flow in stack Measure temperature of stack gases, compare results, should be similar if not, investigate reason for error Travis the stack diameters with pitot tube to determine velocity across ducting, compare results, if not similar then investigate reason for error (this itself could be used as an ILC, between the testing teams Calculate required size of sample probe nozzle, attach to sample probe

Place filter in sample trains filter holder, record filter reference number Insert sample train into stack, ensure nozzle pointing in correct direction of emission flow Once both testing teams are ready start sampling run over a period of 60 min IKS sampling conditions should be logged in check sheets Repeat test on 3 consecutive runs, store filters in clearly marked holders Remove sample train from stack After each test run weigh and calculate moisture capture during sampling, this can be done on site and results can be compared between teams, results should be similar (an additional type of ILC)

Reporting of Results: Indication of performance of individual participants Sample filters are sent to selected laboratory for analysis Results in mg/nm3 are analysed and documented for each testing laboratory Testing teams discuss results and determines if difference between filters are within the accepted tolerance level Copy of calibration certificates: sample pump, pitot tube, temperature sensor

Performance Evaluation: Minimum Acceptance Criteria Evaluation can be based on the z Score or there can be a “Satisfactory Range “ of-2.0 to 2.0 Calculation of uncertainty of measurement Conclusion