Crystalline Silica

Exposure Assessment

A worker cutting brick pavers using a masonry saw.

A worker cutting brick pavers using a masonry saw. Photo by NIOSH

Assessing employee exposure to respirable crystalline silica is critically important to determine the need for exposure controls and personal protective equipment. This page provides NIOSH and other related methods for monitoring and measuring respirable crystalline silica exposure. Prior to exposure monitoring, review each analytical method carefully and consult an American Industrial Hygiene Association (AIHA) accredited laboratory for analysis. An accredited laboratory can provide additional guidance about appropriate sampling methods.

The NIOSH Manual of Analytical Methods (NMAM) is a collection of methods for sampling and analysis of contaminants in workplace air. These methods have been developed or adapted by NIOSH or its partners and have been evaluated according to established experimental protocols and performance criteria. NMAM also includes chapters on quality assurance, sampling, and portable instrumentation.

NIOSH Pocket Guide to Chemical Hazards

The Pocket Guide is a source of general industrial hygiene information on several hundred chemicals/classes found in the work environment. Key data provided for each chemical/substance includes name (including synonyms/trade names), structure/formula, CAS/RTECS Numbers, DOT ID, conversion factors, exposure limits, IDLH, chemical and physical properties, measurement methods, personal protection, respirator recommendations, symptoms, and first aid.

Hardware and Software Requirements for Field-based Respirable Crystalline Silica Monitoring

  • For end-of-shift silica monitoring.

Other Methods