Development of the Regular Interlaboratory Counting Exchanges (RICE) scheme to include visual reference counts and...

Area of Science:

• Occupational Health and Safety
• Environmental Science
• Analytical Chemistry

Background:

• The RICE proficiency testing scheme previously relied on image analysis for asbestos fibre counting.
• Participating laboratories used visual counting methods alongside the established scheme.
• Asbestos clearance operations presented unique counting challenges.

Purpose of the Study:

• To develop reliable visual reference counts for industrial asbestos samples using historical RICE data.
• To establish suitable reference counts and performance limits for asbestos clearance samples.
• To integrate visual reference counts and clearance samples into the RICE scheme.

Main Methods:

• Utilized visual counts from participating laboratories within the RICE scheme.
• Developed reference counts for industrial asbestos samples.
• Developed reference counts and performance limits for asbestos clearance samples.
• Analyzed data variation to define performance intervals on log and square-root scales.

Main Results:

• Established reliable visual reference counts for industrial asbestos samples.
• Created validated reference counts and performance limits for asbestos clearance samples.
• Successfully integrated visual reference counts and clearance samples into the RICE scheme in 1992.

Conclusions:

• Visual counting data from laboratories can provide reliable reference counts for asbestos testing.
• The updated RICE scheme offers improved accuracy for both industrial and clearance asbestos sample analysis.
• Performance limits are adapted to sample density variations for more robust testing.