U.S. Contamination Technical Advisory Group Meets in Birmingham

The U.S. Technical Advisory Group (TAG) to Subcommittee 6 – Contamination Control recently met in Birmingham, Alabama. Twenty-nine committee members came together to continue work on contamination-related standards, focusing on deliverables for the October 2019 TC 131/SC 6 meetings in Milan, Italy where U.S. experts will meet with worldwide engineering counterparts.

Three major projects were discussed:

ISO 11171, Calibration of automatic particle counters for liquids: An International Interlaboratory Study (ILS) has been initiated to:

• Measure the intra-company repeatability and inter-company reproducibility of particle count data obtained using automatic particle counters calibrated with Draft ISO DIS 11171:2019.
• Generate particle count data to be used by NIST to certify consensus standard SRM 2806d that will report sizes in units of μm(c).
• Generate particle count data for NIST RM 8632a that will be used to update Table A.1 in the standard.

The study is expected to wrap-up by June 30 so that analysis can be done and a presentation given during the ISO TC 131/SC 6 meetings in Milan, Italy.

ISO 4405, Determination of particulate contamination level by the gravimetric method: This standard has not been updated since 1991. The U.S. TAG continues its work to define new technical procedures that can be incorporated into an ISO 4405 update. Based on a round robin completed last year, U.S. comments are being given to the project leader for consideration and inclusion.

ISO 23369, Filter multi-pass test under cyclic flow conditions: An ILS was recently completed to:

• Measure the intra-company repeatability and inter-company reproducibility of data obtained using the procedures of ISO/DIS 23369:2013 along with particle counters calibrated with the ISO/DIS 11943:2013 with traceability to ISO 11171: evaluating fine and course filters with ISOMTD and ISOFTD.

The project leader is currently analyzing the results of the study and will present the findings at the next U.S. TAG to SC 6 meeting in June. A presentation will also be given to the international experts in Milan, Italy during the SC 6 meetings in October.

The U.S. TAG on contamination control meets three times per year. If you would like to get involved in the U.S. ISO standards development process, please contact Denise Husenica at dhusenica@nfpa.com.