Under circumstances where a person is likely to be exposed to a workplace environment with gas or airborne material, protection is essential. There are a huge variety of different respirator masks available to suit different conditions, and to ensure that staff are safe, it is necessary to understand which type is required for which situations, in order to provide the best possible protection.
Respirator masks fall into 3 basic categories, which are used under different circumstances, and require different training and precautions to be taken. Essentially, the 3 main types are SCBA (Self Contained Breathing Apparatus), PAPR (Powered Air Purifying Respirators), and finally Escape Breathing Devices.
Self Contained Breathing Apparatus or masks for wildfire smoke are used in industrial circumstances where the user needs access to a guaranteed safe air supply. The name: Self Contained Breathing Apparatus means that the equipment provides a micro environment which is cut off from any external pollutants or chemicals. These are made up of two components. A large tank of air is worn on the back and connected to an airtight mask which is worn over the head.
The tank of air, which is under high pressure, will usually provide enough air for up to an hour, but larger versions are available which last for longer. These are needed under circumstances where there is not a safe air supply available, and where the operator must be provided with a safe supply of air to allow them to survive.
Essentially an industrial SCBA respirator mask is identical to the equipment worn by a diver, and the same precautions such as keeping track of how much air is available at any time must be undertaken. There are two main types of masks, open and closed circuit. With an open circuit system, once air has been exhaled, it will be released into the environment. Where this is inappropriate, for example where the environment must not be contaminated, a closed system can be used. With a closed SCBA system, the exhaled air is stored and can be reprocessed to allow more time for the user to work.
A PAPR or Powered Air Purifying Respirator Mask is generally designed to be worn under circumstances where particulate matter needs to be removed from the air supply, which is otherwise safe to breathe. With these, an air pump with a filter is attached to the belt, and this provides a steady supply of filtered air to a separate mask. There are a variety of situations under which a PAPR mask is the ideal respirator. When using a paint sprayer, or an industrial grinding or sanding device, the air will become contaminated with paint or fine dust that can cause problems if inhaled.
By wearing a PAPR respirator mask, people are protected from things in the air, rather than from the air itself. There are a variety of different filter options available in conjunction with a PAPR mask, and the correct ones for any given situation should be worn. The various filters are sorted by the minimum size of particle that they filter out of the air supply. Some coarser filters are designed to just get rid of relatively large dust particles, while increasingly fine filters are available that are able to remove items as small as virus particles from the air (HEPA filters). Using the correct filter is essential, as the efficiency of the air pump will be governed by the ease with which it can push air through to the breathing mask. If a very fine filter is used, the pump has to work harder, and consequently the battery life will be much shorter, meaning that the user will have to make frequent changes to their system to maintain their protection.
Escape Breathing Devices are sometimes confused with smoke hoods, and although they have many similarities, there are also subtle differences between the two products. An Escape Breathing device is designed to provide the user with a temporary supply of clean and safe air in an emergency.
A smoke hood is especially designed for situations in which the air supply is compromised due to smoke, and these will often merely filter out the high levels of smoke particles in the air in order to ensure a few moments of protection when escaping from a plane. An escape breathing device can be specialised to a particular situation, for example, if you are in an environment where gas can leak, and most devices offer protection in the form of a small canister of gas that will provide a few moments of safety.