By Jason Van Dyke
One of the newest areas in employee exposure is the field of e-waste recycling. The process of taking electronic waste and turning it into raw materials that can be used again is changing just as fast as the electronics that are being recycled. There are many things to be concerned about when talking about employee exposure.
Several years ago, it was common for e-waste recycling to consist of banks of employees simply disassembling electronics and placing the components into bins. Exposure wasn’t that concerning if proper hygiene practices were followed. The facility often had the same exposure concerns that you would find in a traditional manufacturer; that has changed though.
One of the newest forms of recycling appears very close to single-stream recycling that you see elsewhere. Gone is the idea of a worker using a pneumatic tool to quickly disassemble a component; now, whole categories of components are placed on belts and fed into massive shredders and sorters that physically break things down into smaller and smaller pieces, which are separated out using everything from magnets to computer-controlled pneumatic guns.
PSARA has been studying e-waste recycling processes to determine what exposures are possible, how to measure them effectively, and how best to protect employees from exposure. One of the first electronic devices we looked at was copying machines. When a copying machine is sent for recycling, the toner cartridges are removed as is the “waste bottle” where excess toner is collected. Unfortunately, significant amounts of toner still remain inside the machine. Nearly every interior surface of a copier becomes coated with a heavy layer of excess toner during its years of use, and when the copier is shredded, a significant amount of the residual toner is released into the air, creating a dust exposure hazard.
One of the major components of toner is a substance called carbon black, and through exposure testing, PSARA has found that the majority of all dust exposure during copier recycling is actually carbon black exposure. Carbon black has an OSHA permissible exposure limit (PEL) of 3.5 mg/m3 which is significantly lower than the nuisance dust standard. In facilities that recycle copiers, this should be a major concern.
Other concerns include mercury; nearly all backlit LCD screens contain a small fluorescent tube to provide lighting. Obviously, these tubes are not removed before shredding, which means that there is a potential for mercury exposure when such screens are recycled. Of course, even if employee monitoring shows low levels of airborne mercury, it could still be accumulating on surfaces throughout the facility.
Electronics use a disparate number of components, so when e-waste is recycled there are many different employee exposure scenarios, some of which may not be very obvious. If you are in the business of e-waste recycling, it’s important to have an industrial hygiene team that can help you determine how to measure exposures effectively and protect your employees.To find out more about this topic, click here.