Why Choose Safe Environments
- NATA accredited analysis to International and Standards
- Gravimetric and chemical analysis
- X-ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) analysis
- Certified Occupational Hygienist available for further detailed analysis where required
- Sampling NATA accredited to ISO 17020 to determine compliance with exposure standards
Australian Exposure Standard (ES) for Respirable Crystalline Silica
The Australian occupational exposure standards for Respirable Crystalline Silica as Cristobalite, Quartz and Tridymite is 0.05 mg/m3 as a time weighted average for an 8 hour day, 5 days a week. The exposure standards are based on epidemiological and toxicological data, however there will always be some interpersonal variability which is why health monitoring for people at increased risk is critical.
The two analytical methods for the measurement of crystalline silica are:
FTIR is more prone to interferences and there is greater measurement uncertainty of about 30 to 40% because the scanning area is about 8 millimetres where there may be significant differences in the dust deposition on the filter. In comparison XRD uses the majority of the filter scanning about 20 millimetres in diameter the filter is also rotated which reduces the heterogeneity in measurement and consequently reduces the uncertainty.
The detection limits for FTIR and XRD can be comparable but XRD has the ability to adjust the scanning parameters by increasing the measurement time and thereby reducing the limits of detection this can be well below 5 ug.