In 1950 the United States National Safety Council began describing what became known as the “hierarchy of controls.” Often depicted as a pyramid, it lists (in order of importance and effectiveness) the methods required to separate employees from potential hazards on the job. Later, the National Institute for Occupational Safety and Health (NIOSH) worked with this same hierarchy, and the Occupational Safety and Health Administration (OSHA) also began to make use of the pyramid on their website on their Hazard Prevention and Control pages. Proper use of the Hierarchy of Controls in the lab today can help us to remain safe as we work with samples from COVID-19 positive patients.
The best controls in the hierarchy are the first two- elimination and substitution. Unfortunately, these are generally not options when it comes to laboratory work and the biological hazards with which we come into contact on a daily basis. If we eliminated the biohazards, we wouldn’t have any tests to perform.
The first and most effective hazard prevention method on the hierarchy for laboratorians is the use of engineering controls. Engineering controls are defined as those things which reduce or eliminate exposure to a hazard through the use or substitution of engineered machinery or equipment. These controls are favored over others because they are designed to remove the hazard at its source, before it can come into contact with the employee. Often, engineering controls are independent of worker interactions which helps to provide and maintain a high level of protection. The initial price of certain engineering controls can be high, but over the longer term, operating costs are lower, and they can provide a cost savings in other areas of lab processes.
One of the most common engineering controls in labs is a biological safety cabinet (BSC). There are a variety of BSC types, and the safety air containment, the HEPA filtration, and the shielding make them a powerful tool to protect staff from hazards. The CDC has recommended that any testing on samples from COVID-19 patients be performed inside of a BSC if there is a risk for creating an aerosol. Opening coronavirus swab specimens and vortexing samples are good examples of aerosolizing procedures.
Administrative controls, the next level of the hierarchy, seek to improve workplace safety by creating safer procedures in the workplace. Controls can range from the placement of warning signs throughout a facility, employee training programs, and even the use of safety tape. Lab safety procedures are vital, and if they are followed, they can protect staff from COVID-19 and other pathogens. Unfortunately, administrative controls become a weaker level of protection mainly because the onus of safety practices now relies in part on human behavior. If staff follow safety SOPs to the letter, there will be virtually no exposure issues, but we know that unpredictable people don’t always follow the written guidelines. Maintaining a stronger lab safety culture where strict adherence to safety policies occurs will enable your existing administrative controls to be a more useful tool in the battel against lab acquired infections.
The final level of protection from harm in the workplace in the hierarchy of controls is the use of personal protective equipment. By definition, that means that PPE is the least effective method to keep employees from hazard exposure- it is our last resort for safety. Sadly, the COVID-19 pandemic has created a shortage of PPE both for healthcare workers and the general public. Some of this is because of misuse of PPE- people wearing gloves in the stores and in their cars, news anchors wearing N95 respirators in public, etc. There has been confusion about what PPE should be used in healthcare because the guidance has changed often. To keep up with the latest, check the CDC COVID-19 Laboratory web site for appropriate PPE use. Remember, PPE is our last line of protection from this virus and from any other pathogen we work with in the lab setting. Use it properly to keep you safe now and always.
The hierarchy of controls is always available to workers to keep them safe. During this pandemic, there is a new focus on protection, and many questions are being asked. There are references which can help to provide some of the answers (CDC.gov, WHO.int, OSHA.gov, etc.), but if you need more lab safety information, please feel free to send me questions at firstname.lastname@example.org. I will provide the most current safety guidance for your issue. This is a rapidly-changing situation, and information comes from many sources, Make sure you do your best to validate what you hear, and continue to use Standard Precautions and good behaviors to keep you and your laboratory staff safe from COVID-19 and other harmful pathogens.