ALS analyzes dusts that may contain crystalline forms of silica, which can cause silicosis.
About Silica:
Silica is a natural occurring mineral found in rocks and stone commonly used in different building materials such a bricks and concrete. Workers will be exposed to silica when drilling, cutting or otherwise performing operations whereby these materials are being broken and are releasing dust. Both OSHA and NIOSH has identified exposure to silica as a health hazard as dust containing crystalline forms of silica (quartz, cristobalite, and tridymite) may cause silicosis. New Permissible exposure limit (PEL) for crystalline silica was introduced in 2016 highlighting the hazard this kind of exposure presents.
Method Information:
ALS offers analysis for silica using NIOSH Method 7500 by X-Ray Diffraction. NIOSH Method 7500 is able to speciate the different crystalline forms of free silica and differentiate from most interference in bulk or air filter samples. As opposed to traditional methods using IR and visible spectrometry were interferences can and give false positive results.
Reporting Limits:
Crystalline Silica (Quartz): 5 ug/sample
Cristobalite: 5 ug/sample
Tridymite: 30 ug/sample
Sampling procedure:
Sampling is done by pumping air through a PVC filter with a recommended flow rate of 2.7 L/min. Pumps and Cyclone needed for sampling can be rented from ALS on a daily basis. The filter and filter cassettes used for sampling will be provided by ALS and is included in the price for the analysis.
Please click here to see how to calibrate the pump.
