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Silica

The CDC states at least 1.7 million U.S. workers are exposed to respirable crystalline silica in a variety of industries and occupations, including construction, sandblasting, and mining. Overexposures still exist today, regardless of any regulatory movement on OSHA’s part. These overexposures occur in many trades and sectors, including the building and construction industries.

Silica exposure has been known for decades to be the cause of silicosis, which can cause respiratory problems so severe that it can even lead to death. Regulatory agencies in this country are finally starting to take notice and changes are most likely coming that will force compliance with the issue of silica in the workplace.

What is silica? Essentially, silica is a combination of silicon and oxygen. The most common form is quartz. The same sand that we see all over the world is a form of silica and it’s the most common single mineral species on the planet. When it gets dangerous, though, is when it gets small enough to enter the lungs as respirable dust. That is what regulatory agencies provide guidance for.

A part of that guidance is testing for the presence of silica. Forensic Analytical Laboratories, Inc. is proud to announce that we are now an accredited lab for the analysis of respirable silica in air. We do this by a method known as Fourier transform infrared spectroscopy (FTIR). This method is a quantitative method that provides results with the same limits as xray diffraction and is reported the same way, though based on a different instrument method (NIOSH 7603 and ASTM D7946 as opposed to NIOSH 7500 for XRD). Most of the mining industry uses FTIR analysis already, so it’s a time tested methodology. Why did we make the choice to use FTIR instead of XRD? Honestly, it was simply a business choice. We have an FTIR and the knowledge to use it. We are committed to providing our customers with quality analysis and this is a method we are sure of.

The image shown here is an example of the theory: As the amount of silica increases, so does the height of the peaks specific to the species (e.g. the quartz peak at 798 cm-1). The height is directly related to the mass of the silica in the sample.

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Call our lab today at (800) 827-3274 for information on pricing and turnaround times, or feel free to ask us any questions. We look forward to serving your silica analysis needs.