|
Many jobs might expose employees to hazardous materials, causing various health effects. Examples of workplace exposure can be found in factories, chemical plants, manufacturing, and automotive shops.
Honor the Hierarchy of Controls
For workplaces that handle chemicals, there is a Hierarchy of Controls that range from the most effective to the least effective. These are, in order of effectiveness:
- Control at the Source
- Control Along the Path
- Control at the Worker Level
Polychlorinated biphenyls (PCBs) in building material are in the news everyday. The potential health risk and liability make them a widespread concern of EH&S staff, employees, building owners and construction. Download Now
Three Tips at the Source
Preventing chemical exposure at the source is the most effective way of ensuring that your workers are not exposed to the dangerous chemicals they are required to handle to do their jobs.
The three most effective ways to control and prevent chemical exposure at the source are substitution, mechanization or engineering controls, and administrative and work practices controls.
Tip 1: Substitute a safer chemical or process. Many harmful chemicals and processes are used as a matter of tradition although less harmful alternatives exist. Substitution is complex and requires research and experimentation. If successful, however, it is the most powerful and desirable control method. EPA’s Safer Choice initiative provides a list of safer alternatives for many chemicals used in the workplace. OSHA provides a toolkit for employers that want to make the transition to using less harmful chemicals.
If there are no reliable substitutes for hazardous chemicals, you can change the way the process is carried out so it makes the handling of the chemical safer. Sometimes a different process with less potential for exposure can be substituted. Examples include:
- Flow coating or dipping instead of spraying
- Water-based caustic or abrasive- or water-blasting for paint-stripping with solvent-based strippers
- Water-blasting instead of abrasive-blasting
- Controlling dust with a wet method
- Steam-cleaning instead of using solvents
OSHA’s Process Safety Management (PSM) of Highly Hazardous Chemicals Standard requires covered employees to identify processes that pose the greatest risks and begin evaluating those first. This involves performing a process hazard analysis (PHA)—a careful review of what could go wrong and what safeguards must be implemented to prevent releases of hazardous chemicals.
Tip 2: Engineering controls. This type of control implements physical changes to the workplace, which eliminate or reduce the hazard on the job/task. For example, handling of hazardous chemicals can be done by using mechanical arms or robots to keep workers away from the source of exposure. An example would be using an automatic parts dipper instead of manually dipping metal parts in a degreaser.
In this free guide you will learn best management practices to help you easily navigate through the world of PCBs. Download now!
Engineering controls can also involve isolating or enclosing the process. Isolating the source of chemical exposures can be accomplished through actual physical enclosure, preferably with separate rooms or buildings, and closed doors. When isolating a process in a separate room, make sure that the direction of airflow is into the restricted area from the cleaner areas. Therefore, the isolated area must be under negative pressure compared to surrounding areas. This can be done by exhausting extra air from the isolated area to the outdoors using fans in either general or local exhaust ventilation. Exhaust air must be decontaminated before released to the outdoors.
If using a separate room is not feasible, certain operations can be completely enclosed in other ways to protect workers. Examples of enclosing a process include:
- Splash guards
- Hoods over machine operations using cutting fluids
- Use of pumps to handle solvents
- Fume hoods
- Use of wet methods to reduce the generation of dusts or other particles
- Use of glove boxes, which are small units that have two or more ports in which arm-length rubber gloves are mounted. The worker places his or her hands into these gloves to perform tasks inside the box.
- Enclosing individual workers within a special isolated booth or room from which they can observe and control an operation using chemicals. Worker enclosures must have heat and air-conditioning and clean air from an uncontaminated location. They should be under positive pressure to keep out contamination.
Tip 3: Administrative and work practices controls. These types of controls to reduce exposure to chemical hazards involve establishing efficient processes and procedures. This can be accomplished by:
- Rotating job assignments.
- Restricting access only to a limited number of essential employees.
- Isolating by time. The amount of time that employees spend in isolated areas should be minimized. In addition, a hazardous operation can sometimes be performed during the second or third shifts to reduce the number of workers potentially exposed.
In tomorrow’s Advisor, we will discuss steps workers should take to protect themselves and their families from hazardous chemical exposures.