Both powered and supplied air respirators are designed for people that require respiratory protection. Powered air works on the basis of ambient air being drawn through filters to remove contaminants. No breathing effort is required by the wearer; instead a battery-powered fan and motor draw the ambient air through the filter.  Supplied air respirators supply a breathable, regulated flow of air from a compressor via a tube.  

Wearer comfort is a key factor that can make the use of P&SA systems attractive in many applications. Air quality may not be the only hazard a worker is exposed to; some workers may need to use eye, hearing and respiratory protection simultaneously – and in some applications, head protection also has to be factored into the equation. When multiple pieces of Personal Protective Equipment (PPE) are required, the issue of compatibility arises when different items are competing for the same head and face space.

An advantage of P&SA systems is that while their primary function is to protect against respiratory hazards, the fact that their design requires a head top also means that they can be used to incorporate other elements of PPE. The head top is loose fitting and does not require fit testing. 

Simplifying selection

To establish whether gas in air is filterable, 3M offers a guide on its website which lists gases and indicates which filters are required. Powered air respirators are suitable for most hazards providing that the filter is matched to the contaminant. The level of protection offered is often greater to that of a disposable or reusable respirator so it can be a question of how long the user requires respiratory protection or if multiple items of PPE are needed. 

Mobility is also a factor and with supplied air respirators the practicalities of having to be attached to an air supply have to be considered. These systems require a supply tube from the compressor which can be up to 30m long and therefore restrict mobility.  

Another consideration is the condition of the working environment. Some areas may need temperature control in the form of heating or cooling units which are only available with supplied air systems.  However, while a powered air respirator does not have any chilling mechanism, the movement of air across the face has a cooling effect and avoids issues such as misting.

Arguably the most important step in the selection process is choosing the head top, which can be matched to specific industry and application requirements, as well as whether any other PPE needs to be considered. The Versaflo Powered Air Respirator range from 3M, for example, offers a varied portfolio of options suitable for a variety of industries. Broadly speaking, they fall into three categories: head covers with hoods, rigid head tops and specially-designed welding head tops.

In some applications, a simple hood is deemed sufficient. If there is a particle-carrying mist in the air which may become liquid when settled, there are head tops with greater coverage. Where impact protection is required, a higher level of head and eye protection is offered by rigid visor or helmet types of head top. For welding applications where powered air devices are particularly popular, there are specially-designed head tops which offer a high level of respiratory protection with the added benefit of a cooling air flow.

With powered and supplied air systems, there are ways of protecting your investment. One is to ensure proper training for the people both using and maintaining the equipment. There is a lot of support available for this: 3M provides detailed care and maintenance packs, which cover the full regime, including COSHH record requirements. There are also accessories available which help prolong the life of the equipment and protect it from damage. 

While P&SA options are often seen as the more complex choice, they can be the most appropriate and overall the most straightforward solution for many applications. They are easy to customise to the requirements of specific industries and can solve workplace problems such as PPE compatibility, helping to ensure employee compliance and confidence in protection.