Although elimination and substitution are separate controls in the hierarchy of control measures, they are also considered engineering controls because they are designed to remove the hazardous source before the worker makes contact. Other forms of engineering controls include:
Reduce or remove hazards by separation in time or space. (May be particularly helpful in a shared lab space where different types of chemicals are being used.)
Place the material or process in a closed system.
Move hazardous materials where fewer workers are present.
- Guarding and shielding
Install guards to provide protection from moving parts or electrical connections.
Shielding provides protection from potential explosions
Use fume hoods, fans, air ducts and air filters.
While engineering controls seek to eliminate hazards, administrative controls aim to minimize a lab worker's exposure. Administrative controls are the existing safety rules and protocols put in place for workers in the lab to follow. Following are examples of administrative controls:
Personal Protective Equipment (PPE)
Even though the hierarchy of control measures indicates PPE is the least effective of control measure, it should absolutely be used, in case other control measures fail. The success of PPE depends in part on whether or not lab workers actually use it.
Eye goggles, hearing protection, and protective clothing (e.g., lab coats and gloves) are the most recognizable and most used PPE in the lab.
PPE is always essential, and especially critical in the following circumstances:
- When engineering controls are not feasible or they do not totally eliminate a hazard;
- As a temporary control while engineering controls are being developed;
- In emergency situations.