Let us now look at the second major control group that we have talked about and that’s primary containment and barriers, which consists of safety equipment and personal protective equipment or PPE. The primary barriers that we often talk about in biosafety are usually engineering controls, like the biosafety cabinet, the animal enclosures and directional air flow. Personal protective equipment are things like gloves, masks, eye protection, gowns, respirators, and hearing protection.

 First, let us look at three common ventilated engineering controls. These are all primary barriers that you may see in your laboratory. On the left-hand side you see that biological safety cabinet. In the middle, the chemical fume hood and on the right-hand side the clean bench or the laminar flow cabinet. We will discuss each of these in more detail later. As you see, they all move air in a different fashion, but they are all engineering controls.

 If you look at the levels of protection they provide, you can see that across the top we have personal protection, product protection, and environmental protection. The fume hood only provides personal protection because it draws air away from you. The clean bench only provides product protection because that is what it was designed to do – protect the product. That is why it is called a clean bench. The Class I biosafety cabinet, protects personnel and the environment, while the Class II biosafety cabinet protects all three – personnel, product, and the environment. The class III biosafety cabinet also protects all three, but to a higher degree.

 Now, turning our attention to personal protective equipment or primary barriers. As you know, PPE is commonly used in the laboratory. A variety of different areas of the body are covered, therefore blocking various routes of transmission. You may use gloves, coats, gowns, shoe covers, booties, respirators, face shields, safety glasses, safety goggles and hearing protection. What type of PPE is used and how much, is very much dependent upon the risk assessment.
Gloves, come in a variety of different sizes and styles. Depending on what you are doing and the hazard, the right kind of gloves should be selected. There are gloves that protect against microbial pathogens, chemicals, heat, cold, cuts, punctures, water and more. In addition, you may use double gloving as well. Each glove has its own protective capability and when you combine them, you get the best of both. The selection of gloves really depends on the situation you find yourself in and the hazards presented.

 Eye and face protection is also very important. The face has a lot of entry points for pathogens via the mucous membranes of the eyes, nose, and mouth. You see here a variety of different eye protections. On the top left-hand side, you can see just normal eyeglasses. On the bottom left-hand corner, you can see goggles. In the middle, you see somebody wearing eye glasses with a face shield and on the bottom right-hand, corner safety glasses. The glasses on the top right-hand corner, maybe very stylish but will not give you very much eye protection. Each of the different eye protection types have advantages and disadvantages. Which type of eye and face protection you choose is again very dependent upon a good risk assessment.

 Nose and mouth protection. As you know, there is a potential for pathogens to enter the body through the mucus membranes of the face, if these are exposed. Therefore, we want a barrier over those membranes whenever there is a possibility that you may get splashed in the face with a pathogen. There are a wide variety of options to choose from when it comes to nose and mouth protection. Simple surgical masks are the easiest and most affordable option, but respirators will also work. Masks, in combination with eye protection like a face shield, goggles or glasses will create barriers to all the mucus membranes of the face. You need to do a thorough risk assessment to determine which is the most suitable and cost-effective option to protect your nose, eyes, and mouth.

 Respirators. If your risk assessment indicates that there may be potential aerosols created that cannot be controlled by a primary containment device, then you need to protect your lungs from these aerosols with a respirator. An N95 respirator is one of the more common ones but there’s other ones that you can choose from. As with other PPE, respirators come in a variety of different sizes and styles and expense. A risk assessment will help you choose the correct one.
Here is a short video to summarize a lot of these concepts and ideas, called biosafety 101. This is from the Canadian government and it summarizes many of those practices and techniques we talked about and shows you an overview of good laboratory practices. So please watch this video.

That was a very good overview of biosafety in general and a summary of some of the basic good laboratory practices that we talked about earlier on. Now let us look at some laboratory design features that support the previous controls.