An In-field Method for the Calibration of Instrumentation for Respirable Crystalline Silica Analysis

<p dir="ltr">Crystalline silica is a carcinogen which is associated with many diseases including silicosis, chronic obstructive pulmonary disease (COPD) and lung cancer. These diseases come about because of exposure to and inhalation of respirable crystalline silica (RCS) which is produced during work activities such as tunnelling, blasting, construction, quarrying, cutting, and polishing engineered stone benchtop materials. For dust particle to be deposited in the lungs of humans, it depends significantly on the particle size or aerodynamic diameter. Dust particles are referred to as respirable when they have aerodynamic diameter less than 10 μm and a median cut point (d50) of 4 μm. These particle sizes can penetrate the alveoli. Some of these activities release dust that contains a very high concentration of RCS. When workers are continuously exposed to these size fractions, and they inhale them over time it affects their health and their ability to carry out tasks effectively. These result in them being retired early from their work and battling with the effects of their conditions such as silicosis for the rest of their lives To measure the RCS concentration in dust in a workplace, dust is sampled onto filters, which are normally sent to commercial laboratories that are off-site and in certain countries the testing laboratories are in another country. The results can take up to 6 weeks before they are received by which time the work environment has usually changed due to various factors, such as some workers may have been moved from the work area to another, production in the area sampled may have ceased and moved to a different section of the work site. Workers may also have been exposed to silica from the dust as production has continued while waiting for the results of the samples previously collected. The situation above is common in developing countries and also remote sites in developed countries all of whom would benefit from more timely and if possible, accurate onsite RCS analysis. If such data was available, operations could use it in their risk assessment process thus, implement enhanced health and safety procedures before workers are potentially exposed.</p><p dir="ltr">A systematic literature review was undertaken to investigate previous research that has attempted to address the issue of timely onsite RCS measurement and identify gaps that this research has addressed. The gaps identified were the paucity of research around standardized method of dust collection for in-field RCS analysis and the need for more research around in-field RCS analyses and the use of portable RCS instrumentation. Also included were the absence of a calibration method for RCS measuring instrument that can be deployed in-field, and the absence of a standardized approach to overcoming the impact of interferences present in host materials.</p>