Understanding the Types of Respiratory Protection
Selecting the correct respiratory protection is vital. There are many hazards in the workplace that can cause both short and long term respiratory damage. Below is a breakdown of the different types and styles of respirators available to help protect workers. If you are unsure of your requirements, or would like further assistance please contact ATOM Safety.
There are two types of respiratory protection – negative and positive pressure. Negative pressure relies on the user drawing air through the cartridge or filter, whereas positive power units are battery operated, pulling air through the cartridge or filter. Negative respirators can be either disposable or reusable, whereas positive pressure units are reusable.
Negative Pressure – Disposable
Pre-Formed or Flat Fold
Disposable respirators are available in flat fold and preformed variations. Both varieties are designed to fit the face, covering the mouth and nose. Flat fold masks come ‘flat-packed’ and need to be expanded before wear. They generally have a better fit as they are flexible and can mould to an individual’s face shape. Pre-formed are packaged ready to wear.
Valved or Un-Valved
Disposable respirators are available in valved or un-valved options. The purpose of the exhalation valve is to provide extra comfort as it assists in reducing a build up of heat and moisture.
Activated carbon filters assist with removing nuisance odours and offer protection from low levels of specific gases and vapours.
How to Fit a Disposable Respirator
Hold the mask in hand with the nose piece up. Allow headbands to hang freely.
Position the mask under the chin, covering mouth and nose.
Pull the headband over the head.
Check fit and press metal nose clips gently.
A mask has been fitted correctly when there is a complete seal around the mouth and nose, and no unfiltered air is able to enter the face mask area.
Ensure that the wearers face in clean shaven to allow for a correct fit. Facial hair creates small gaps between the face mask and the skin. Even one-day stubble may effect the seal and let small amounts of unfiltered air into the face mask. Masks should be fit tested to ensure optimal protection is achieved.
Negative Pressure – Reusable
Full or Half Face Respirators
Reusable respirators come in both half face and full face varieties, both of which offer protection from various particulates, gases and vapours. Half face masks provide a seal which fits over the nose and under the chin. Combined with appropriate filters, a half face mask will provide protection against particulates, gases and vapours.
Full face masks provide an improved seal and therefore improved protection compared to the half face mask. A full face mask covers the eyes and face which provides protection against irritating vapours, mists, and splashed chemicals. Converting from a half face mask to a full face mask with a P3 particulate filter provides 50 times more protection.
Reusable Filters and Cartridges
Filters are designed to be used against specific gases and vapours. They are individually marked according to what vapours and/or gases they can be used against. There are three classifications of particulate filters – P1, P2 and P3. Each offers a different level of protection against particulates and airborne toxins.
Vapour & Gas Filters
Filters are individually designed to be used against specific gases and vapours. Filters are marked according to what vapours and/or gases they protect against.
Filters are also classed by absorbency, 1 being low to medium, 2 being medium, and 3 being high absorption. The higher the absorbency, the higher concentration of gases and vapours the filter effectively works at.
Filters typically protect against a number of gases and vapours, not just one. A filter that protects against organic vapours (boiling points >65°C), Acid Gases, Sulphur Dioxide, and Ammonia all at Class 1 absorbency would be displayed on product as:
When Should Filters be Changed?
During use particles will build up in the filter, slowly allowing less air to pass through. This is known as breathing resistance. Filters should be changed when breathing resistance makes it too uncomfortable or laborious to breathe properly.
The exact time to change your respirator is a personal choice, dependent on how sensitive you are to breathing resistance.
Your filter should also be changed if it becomes damaged in any way.
Positive Pressure Respirators
Positive pressure respiratory systems utilise a battery powered unit that either pulls air through a cartridge or filter, or supplies air through an airline or self contained unit. There are two options, PAPR or SCBA.
PAPR (Powered Air Purifying Respiratory)
A Powered Air Purifying System is a battery operated respirator unit that can be either full face or half face. The mask is attached to a breathing tube which utilises a battery operated blower unit that draws air through the appropriate filter or cartridge to remove any contaminants. There are many variations of PAPR units available to suit the user’s requirements.
CleanSpace’s unique PAPR design places the battery weight behind the head, reducing strain on the neck, or lower back whilst improving mobility by removing any hoses or cables. This design also reduces the product’s overall weight. CleanSpace offer the lightest PAPR respirator on the market, weighing in at just 500 grams. The on-board battery is rechargeable, and lasts a full working day (up to 8 hours).
SCBA (Self Contained Breathing Apparatus)
A Self Contained Breathing Apparatus or SCBA is a respiratory system that is a portable ready supply of safe breathing air that is used when atmospheric conditions are unknown, or when there is an immediate danger to life or health (IDHL) eg. Emergency response. Depending on the model, air supply can last from 30 to 60 minutes.
SBCA respiratory systems are designed for use when there is immediate danger to life. They need to be donned quickly, be comfortable, have excellent visibility and allow communication between wearers. MSA’s SCBA systems are ergonomically designed to reduce stress and strain. The face mask has a wide 86% field of view and speaking diaphragm to improve spatial awareness and communication. Premium models also include 2-way radios and thermal imaging cameras.
Escape respirators are portable devices designed to be used during emergency escape from zones containing hazardous gas. Unlike other respirators, escape respirators can only be used for a limited period of time. Most models will provide the user protection for under one hour.
Emergency respirators should be made available in any situation where workers may be exposed to harmful gases or fumes. When selecting an escape respirator there are two options – a filtering device, or an independent air supply system. Filtering devices are more economical and work well if the potential hazardous gas is known. If this is not known, opt for an independent air supply.
Every workplace is different, and requires a tailored safety management program in respiratory protection. Contact ATOM Safety today to discuss your respiratory protection requirements.