- By Treven Pyles
By virtue of OSHA's new rule, which became effective on June 23, 2016, workers in the construction industry will be exposed to lower levels of silica dust on the job. Silica is a naturally occurring mineral component in sand and stone, which are present in numerous building materials construction workers handle on a regular basis, such as brick, cement, drywall, and plaster. Like asbestos, silica was deemed a human carcinogen by multiple health agencies and it becomes a hazard only when airborne. While abrasive blasting releases the highest amount of silica dust in the air, there are plenty of other activities which pose a serious risk to the wellbeing of construction workers.
According to OSHA, the aim of the new standard is to reduce the incidence of occupational lung disease among construction workers by requiring employers to maintain the air concentration of silica below the permissible limit, as well as to design and implement exposure control plans. They will also have to offer employees who regularly work with silica-containing materials a set of medical exams every 3 years so as to monitor their health and timely detect any potential effect of exposure. The compliance deadline for employers in the construction industry is September 23, 2017. OSHA estimates that the enforcement of the new silica rule will save more than 600 lives and prevent approximately 900 cases of silicosis - the most common disease exposure to silica causes - annually.
Silica is present in over 600,000 workplaces within the U.S. construction industry at the moment, which means approximately 2 million people are exposed to it on the job. According to OSHA, over 840,000 of these employees are frequently in contact with silica concentrations which exceed the new permissible limit. Any activity which releases silica particles in the air creates a health hazard, to a greater or lesser extent. If they disturb the following building materials without wearing reliable protective equipment, construction workers are bound to inhale silica dust, which may lead to debilitating pulmonary disease within several years:
Out of the entire range of activities construction workers may perform to the above materials, abrasive blasting is by far the most dangerous when it comes to silica exposure. It entails propelling a stream of abrasive material to a stone, concrete, or metal surface under high pressure with the purpose of removing paint or rust. Abrasive blasting can also shape or roughen various surfaces. When the operation involves sand, it is referred to as sandblasting, and construction workers who make use of this abrasive material are at highest risk, since sand contains silica. Nevertheless, there are other activities which generate harmful amounts of silica dust as well, such as:
Interestingly, the tools construction workers use to perform these operations can influence the amount of silica dust released in the air significantly. For instance, surface grinders produce a concentration of airborne silica which is 79% higher than OSHA's new permissible exposure limit, whereas the toxic dust excavators and bulldozers generate exceed it only by 7%.
The inhalation of silica dust in occupational settings can result in multiple types of pulmonary disease, silicosis being the most widespread among construction workers. As it gradually causes extensive damage to lung tissue, silicosis ends up restricting breathing capacity tremendously, which is why most people who suffer from this disease experience very distressing symptoms. Depending on the severity of exposure, silicosis may ensue within a few weeks to as long as 20 years after the first contact with silica dust. While there is no known cure, the disease can be successfully managed with treatment, which typically involves medication and oxygen therapy.
Between 3,600 and 7,300 new cases of silicosis occur every year in the U.S. However, by reason of increasingly effective workplace regulations, the rate of mortality has been declining over recent decades. Nowadays, silicosis is responsible for approximately 100 deaths in the U.S. annually, which is undoubtedly a great improvement by contrast with the 1,065 victims registered in 1968. In addition to silicosis, exposure to silica dust can also cause the following diseases, which may stem from the previous or develop independently:
The primary change OSHA intends to operate within the construction industry concerns the permissible exposure limit (PEL), which, starting with September 23, is going to be 50 micrograms of airborne silica per cubic meter of air (50 mcg/m3), averaged over a period of eight hours. Considering the previous PEL, 250 mcg/m3, it is without a doubt a major improvement, reducing the amount of silica dust construction workers are exposed to by 80%. In order to permanently keep silica levels below the limit, employers will either have to use a control method provided by OSHA or assess exposure themselves and subsequently decide on the most appropriate way to manage it.
Additionally, OSHA's new silica rule includes the following requirements which employers in the construction industry will have to comply with:
Using NIOSH method 7500 by X-ray diffraction, which can identify three different forms of crystalline silica with high accuracy, we provide reliable silica testing services to employers in the construction industry. With over 25 years of professional experience, our industrial hygienists perform high-quality silica testing for numerous companies in the construction industry and will gladly assist you as well. If you are a construction employer, please feel free to contact us and we will promptly help you meet OSHA's new silica requirements to ensure a safe and clean environment for your workers.Call 205.328.9200