PAPR, or Powered Air Purifying Respirator, is a battery operated respiratory unit. Rather than being negatively powered like traditional face masks, PAPR units are positively powered. This means that clean, filtered air is driven into the filter and mask through a battery powered blower. This design gives them an advantage when it comes to airborne hazards that require P3 category filters such as crystalline silica, asbestos and welding fumes, and can provide a more comfortable wearing experience over longer a period of time.
How Do PAPR Respirators Work?
PAPR respirators use a rechargeable battery pack to power an air blower. This blower pulls contaminated air into the particulate or gas filter, then into the face mask. Depending on the model, this air may blow constantly or be activated by breath. Used air then escapes from the face mask through an exhalation valve.
Like most respirators, PAPR units use disposable particulate or gas filters to filter the contaminated air. These filter must be replaced once degraded. Many models indicate with a light or alarm when this is the case.
Read more on particulate and gas filters
Benefits of PAPR Respirators
Ease of Wear
PAPR respirators are comfortable to wear, almost eliminating any breathing resistance. As the air is pushed into the face mask, rather than pulled, the wearer can breathe more naturally. This is especially important if the wearer is undertaking laborious activities or wearing respiratory protection for an extended period of time.
Another advantage is the face mask air circulation provided by the air blower. The movement of air can cool the wearer in hot, humid environments. This is most noticeable in full face models. It's important to note that PAPR respirators do not have the ability to heat or cool air before is it is delivered to the face mask.
High APF (Assigned Protection Factors)
Assigned Protection Factor (APF) is the number given to a respirator that indicates its level of protection. This can range from 10 to 100+. A full face PAPR respirator can have an APF of up to 1,000 (once fit tested). This is significantly higher than half face, negative powered respirators, which may only have an APF of 10. This makes these respirators ideal for hazardous chemicals and dust, infectious substances and welding fumes.
Read more on respiratory fit testing
Position of the Filter
In many PAPR models the particulate or gas filter is positioned behind the wearer, in a protected position. This means that the filter itself may not receive the full impact of the airborne hazard (Eg. dust particles being generated by an electric sander). This makes the clean air easier to achieve and the filter last longer.
When to Wear PAPR Respirators
To know if you and your team require PAPR respirators, you must conduct an audit to determine:
What your potential hazards are
If respiratory protection is required
If so, what level of respiratory (protection factor) is required
As a guide, a PAPR respirator should be worn whenever your minimum protection factor is above 50, and must be worn when your minimum protection factor is above 100.
PAPR Welding Helmets
Welding requires specialised PPE to protect the welder from its combined hazards including arc flash, high heat, projectiles and the fumes that are produced by welding. It can be laborious to wear separate pieces of PPE to protect the face and the respiratory system. If you weld frequently, a specialised PAPR respirator welding helmet will be useful to you. The combined unit includes all of the features and benefits of a regular PAPR unit, but with the added safety of a welding helmet.
Welding PAPR units are used mostly to protect the user from the various welding fumes caused by MIG, TIG and Stick welding with materials such as aluminium and steel. Some fumes released, that a PAPR unit can protect you from include aluminium oxide, metal oxide smoke and metallic powder.
Most models also include a spark filter which screens out hot metal particles.
3M Speedglas Adflo
One of the most popular PAPR welding models is the rechargeable, battery powered Speedglas Adflo. Unlike the CleanSpace model, the Adflo's air filter is worn around the waist, putting the weight of the unit on the lower back. Air is them blown up a tube into the top of the welding helmet. The clean air flows at a constant rate of 170L/min, regardless of the batteries charge or the state of the particle and gas filters. The air is directed into the helmet in a fashion that allows for ample air circulations, making sure that breathable air is distributed evenly throughout the helmet.
The Adflo includes a long lasting battery which, dependent on conditions, can last up to 10 hours. You can also get back to work more quickly with its one hour rapid charge.
The Adflo is connected to 6 different welding helmet options, in various grades and price points. Options include standard welding helmets, flip up visors and additional head protection.
To find out more about Speedglas welding helmets contact ATOM Safety.
PAPR Hygiene & Maintenance
In the interest of hygiene, where practical each user should be given at least their own face mask. This should be cleaned and disinfected after each use to maintain proper working order. Standard AS/NZS 1715 - Selection, Use and Maintenance of Respiratory Protective Equipment states that no device should be reissued without being properly cleaned and disinfected after the last use.
Before wear, it is vital that each respirator must be checked to ensure that it is in proper working order.
To find out a PAPR respirator is the right fit for you and your team, contact a member of the ATOM Safety team.