At a glance
Assessing worker exposure to respirable crystalline silica is important to determine the need for exposure controls and personal protective equipment. Prior to exposure monitoring, review each analytical method carefully and consult an accredited laboratory for analysis.
![Safety manager performing work assessment and writing notes.](/niosh/media/images/IHassessment2.jpg)
Assessment methods
The NIOSH Manual of Analytical Methods (NMAM) is a collection of methods for sampling and analyzing contaminants in workplace air. These methods have been developed or adapted by NIOSH or its partners. They have also been evaluated according to established experimental protocols and performance criteria. NMAM includes chapters on quality assurance, sampling, and portable instrumentation.
NIOSH Method 7602
- NIOSH Method 7602 – Silica, Crystalline, by IR is recommended if there are minimal amounts of amorphous silica and silicates in the sample.
- NIOSH Method 7603 – Silica in Coal Mine Dust is for using when analyzing for silica in coal dust.
- The NIOSH Pocket Guide to Chemical Hazards is a source of general industrial hygiene information on several hundred chemicals found in the work environment.
- Hardware and Software Requirements for Field-based Respirable Crystalline Silica Monitoring is used for end-of-shift silica monitoring.
Other Methods
- Occupational Safety and Heatlh Administration (OSHA) Method ID-142. This OSHA method is similar to NIOSH Method 7500 and can be used in most sampling situations where silica is in a mineral matrix (i.e., in concrete or asphalt).
- Mine Safety and Health Administration (MSHA) Method P7. Method for sampling coal dust.
Engineering controls
Engineering controls are interventions that can be used to eliminate or more safely work around hazards. Incorporating engineering controls are beneficial because they reduce work-related injuries and illness. To control silica exposures, there are wet methods that use water sprays to control dust. There are also dry methods like ventilation controls that use vacuums and high efficiency particulate air (HEPA) filters.
NIOSH Engineering and Physical Hazard Reports
The NIOSH Engineering and Physical Hazard Reports include research described in an assortment of report types. Go to Workplace Survey Reports to view these reports.
Directory of Engineering Controls
The NIOSH Directory of Engineering Controls provides links to engineering control-related webpages, projects, programs, tools, and resources to improve workplace health and safety.