We’ve seen them in countless movies, especially ones involving alien attacks or nuclear weapons. We’ve even seen them on the discovery channel, as crime scene investigators poke through the shrapnel and debris left over by bomb blasts and fires. Hazmat suits, also known as biohazard suits and NBC (Nuclear, Biological, Chemical) suits are designed to protect wearers from the dangerous substances that they are likely to encounter in their work.
These suits have two chief functions: gas or vapour protection and splash protection. Gas protection suits are designed to shield the wearer from just about anything except radiation. They are totally encapsulated and are usually over-inflated to protect the wearer from contamination even in the unlikely event that the suit is breached. They are worn with a self-contained breathing apparatus (SCBA) so that the wearer can breathe easily within the suit.
Suits that are designed to protect against splashes or anything liquid are also fully encapsulated with an SCBA, but needn’t be airtight, as gas protection suits are. As a result, they don’t offer any protection against airborne contagions.
In the US, Hazmat suits are categorized on four levels:
o Level A suits, which are completely encapsulated with an SCBA. These suits are airtight to provide protection against direct and airborne contact with contagions. Gas protection suits fall under this category. Owing to the necessary thickness and relative inflexibility of these suits, as well as the limited air supply, they can’t be worn for long periods of time, and should be removed usually after around 20 minutes.
o Level B suits can be either fully encapsulating or offer only partial protection. They can be worn with or without an SCBA. Splash protection suits are categorized as Level B suits.
o Level C suits are merely coveralls that provide an adequate measure of protection against moderate splashes and run-of-the-mill dirt. They aren’t worn with an SCBA but can be worn with a gas mask or respirator should the need arise.
o Level D suits aren’t specialised suits as such. Ordinary industry-specific protective gear, such as boiler suits and face masks, falls under this category. Tail Activewear Coupon
Hazmat suits and biohazard protective equipment are further rated according to permeation rate, breakthrough time, and degradation to help you determine the level of protection that you require.
Permeation rate is the speed with which chemicals and contagions move through the protective material. If the permeation rate is high, it means that the contagions move quickly through the material. Breakthrough time refers to the total time it takes for contagions to completely permeate the suit. It gives an indication of the lifespan of particular protective items. Degradation measures how quickly material physically deteriorates once it has come into contact with a contagion. Depending on the type of contagion, material can become brittle, harden, soften, or in worst case scenarios, actually dissolve.
Considering that not all protective equipment is made equal with regard to permeation, breakthrough time and degradation, it’s important to carefully consider the specifics of the task at hand before donning any protective clothing. For instance, you need to identify all hazardous materials with which you are likely to come into contact. You also need to consider whether there is a risk that your protective material will be punctured or torn. You need to estimate the level of contact that you will have with the contagion. Will you have to wade knee-deep through the hazardous substance or will you only have to analyse it through a microscope?
Lastly, you need to consider all incumbent decontamination procedures. It’s no good kitting yourself out in an airtight suit with a SCBA and gloves taped up to your elbows, and then dumping it, toxic waste splatters and all, in an open bin where any passing Joe will have access to it. The protective measures that you take at the end of a dangerous assignment are just as important as the ones you take to see that assignment through.