Respiratory Protective Equipment (RPE)

Introduction to RPE

In this post we're going to touch on some different areas in the vast arena of Respiratory Protective Equipment. We're going to start with:

• An introduction to RPE
• Types of Respiratory Protection
• RPE Filters
• RPE Maintenance free masks
• Selecting RPE
• Matching filters, substance and form.
• The suitability of different RPE

Respirators and breathing apparatus are used by workers to protect their health from many harmful dusts, mists, vapours, gases and fumes. Respiratory Protective Equipment (also known as RPE) remove harmful substances which would be breathed in without said protection. These hazards occur in a variety of circumstances, including cutting materials such as stone, wood or metal, using solvents such as turpentine, dusty powders and welding.

RPE comes in different sizes to suit different workers depending on the user and the task at hand. All respiratory protective equipment must be both:

Adequate - Correct equipment for the hazard and reduce exposure to the required levels in order to protect the user's health.

Suitable - Correct for the wearer, task and environment in such a way that there are no additional risks to the user.

According to the HSE in order to select RPE that provides the wearer with the required protection level you must understand:

• the hazardous substance and the amount in the air (exposure)
• the form of the substance in the air (vapour, gas, particle)
• The type of work being carried out
• any specific wearer requirements such as spectacles, or hearing protection.

If there is likely to be a lack of oxygen in the environment in which the user operates, specialist breathing apparatus will be required and only those trained should be using such equipment.

 

Types of respiratory protective equipment

There are two types of RPE, which are then split into sub-groups. Those are respirators and breathing apparatus.

Respirators - There are two types of respirators which remove contaminants and harmful substances from the air:

• Non-powered respirators which rely on the user's breathing to draw air through the filter.
• Powered respirators which use a motor to provide a clean supply of air through automatically passing air through the filter.

Breathing apparatus - this RPE requires some form of air cylinder or compressor (known as an independent source) to supply clean air to the user.

 

Respirators and breathing apparatus are then split into two further sub-groups:

Tight-fitting facepieces (aka masks) must have a firm seal with the user's face, available as both powered and non-powered respirators and breathing apparatus. When using respirators or breathing apparatus which require a firm seal a face fit test should be carried out to ensure the RPE is protecting the wearer.

Loose-fitting facepieces which prevent contaminants leaking by the user providing enough clean air, this type of RPE is only available as powered respirators or breathing apparatus.

 

Respiratory Protective Equipment - Filters

The filter is one of the most vital components of any respirator which are available for liquid particles, vapours or gases (see picture). Filters can be purchased both as a part of the respirator or separately. The correct filter MUST be chosen in order to provide the adequate protection for the user. See the table below with a very brief guide:

Type	Colour				Hazard Type	Examples	Maximum use level
A1	A1				Organic gases and vapours, boiling point >65C	Working with solvents from paints and adhesives	10x WEL (half mask) 20x WEL (Full mask) OR 1000 ppm whichever is lower.
A2	A2				Organic gases and vapours, boiling point >65C at higher concentrations	As A1 above but with higher concentrations or prolonged use.	10x WEL (half mask) 20x WEL (Full mask) OR 5000 ppm whichever is lower.
A1B1E1	A1	B1	E1		As A1+ Organic gases and vapours + acid gases. (NOT Carbon Monoxide).	As A1 and working with chlorine, bromine, hydrochloric acid and other acid gases.	10x WEL (half mask) 20x WEL (Full mask) OR 1000 ppm whichever is lower.
A1B1EK1	A1	B1	E1	K1	As ABE1 plus ammonia and ammonia derivatives	As ABE1 plus ammonia and ammonia derivatives	10x WEL (half mask) 20x WEL (Full mask) OR 1000 ppm whichever is lower.

 

Maintenance free particulate respirators

There are three basic levels of protection within these most common respiratory protection which are used for particles, as they are simple to use and relatively inexpensive in comparison to other RPE. These respirators may also be valved or unvalved, (the valved being cooler to wear) and may contain carbon or other products to remove nuisance levels of certain gases and vapours. (See picture). The three levels of protection are outlined below:

	FFP1	FFP2	FFP3
Protection	APF 4	APF 10	APF 20
Usual uses	Non toxic dusts, mists and fumes based on water and oil. Working with non toxic dusts, mists and fumes, hand sanding, drilling and cutting.	Harmful dusts, fumes and aerosols based on water and oil. Working with softwood, glass fibres, metal and plastics (besides PVC) and oil mists.	Harmful and carcinogenic dusts, fumes and aerosols based on water and oil. Working with highly toxic metals, hardwood, radioactive and biochemical active substances as well as oil mists.

 

Selecting Respiratory Protective Equipment

 At the point of selecting RPE, you must have already carried out the COSHH risk assessment to identify which hazardous substances are occupying your workplace. The HSE reminds that there are two key areas to consider:

• Any products used at work that are classed as hazardous substances will come with a safety data sheet (SDS) provided by the supplier. All products which are classed as 'dangerous for supply' must be provided with this sheet by law and it must contain the following information:

-health hazards

-forms of the substances contained in the product

-type of RPE necessary for its use

• Work activities, such as cutting or heating materials, may generate harmful substances as a result, which in turn will contaminate the air in the form of dusts, mists, gases or fumed.

I strongly recommend reading the 'Selecting RPE' table within HSG53 which can be found http://www.hse.gov.uk/pUbns/priced/hsg53.pdf on page 12.

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The substances we are trying to protect our employees from can take multiple forms, such as particles, vapour and gas. It is thought by some however that these hazards only happen one at a time. This is NOT true. Hazards can take multiple forms at the same time, for example when spray painting. You must ensure that the selected RPE protects against all forms the hazards take within your workplace.

Note:

• solid and liquid forms will be present as particles.
• fine sprays and mists are made up of liquid particles (aka droplets).
• fumes are very fine solid particles and not gas or vapour.
• smoke, fume and airborne liquids require RPE that is suitable for use against particles.
• Under certain conditions, volatile liquids may under certain conditions become airborne as both particles and vapour.

 

Matching filters, substance and form

The filter material within is the part which filters out hazardous substances, different filter materials filter different substances and forms with there being two basic filter types; gas/vapour filters and particle filters.

So it's important to remember the following points:

• Airborne liquids in the form of fine sprays and mists and solid materials, including dusts, fibres, smoke and fumes require a particle filter.
• When air is breathed in it passes through the filter removing the contaminants.
• The whole respirator can be made of filter material or have separate filters which are attached.
• Particle filters do not protect against gas or vapour.
• Gas/vapour filters do not protect against particles.
• NEITHER filter can be used in oxygen-deficient atmospheres, this will require specialist breathing apparatus.
• Some environments require a combination of both gas/vapour and particle filters.

 

Suitablity	Respirators
RPE Type	Disposable half-mask - particles	Reusable half mask - particles	Reusable half mask - gas/vapour	Full face mask - particles	Full face mask - gas/vapour	Powered mask	Powered hoods/ helmets
Particles	YES	YES	NO	YES	NO	YES	YES
Gas/vapour	NO	NO	YES	NO	YES	YES	YES
Wear time	<1hr	<1hr	<1hr	<1hr	<1hr	>1hr	>1hr
APF4	YES	YES	NO	YES	NO	NO	NO
APF10	YES	YES	YES	YES	NO	YES	YES
APF20	YES	YES	NO	NO	YES	YES	YES
APF40	NO	NO	NO	YES	NO	YES	YES
APF200	NO	NO	NO	NO	NO	NO	NO
APF2000	NO	NO	NO	NO	NO	NO	NO

 (Credit Health and Safety Executive)

Glossary

• FFP - Filtering Face Piece
• FFP+ 1 (low), 2 (medium), 3 (high)
• APF is the 'Assigned Protection Factor' which indicated the level of protection provided by the mask.
• WEL is the 'Workplace Exposure Limit' which is the maximum amount of airborne contaminant allowed when averaged over a specific time frame. Depending on the contaminant, the WEL will vary, as well as this there are two time period which can be used to measure the WEL: the Time Weighted Average (TWA) which is an 8 hour period and the Short Term Exposure limit (STEL) which is a 15 minute period.
• NR when following FFP on respirators, this designates that the mask is NOT reusable, as such you should use it once and dispose.
• R designates that the mask IS reusable. Care should always be taken however to ensure that the mask is still providing the required protection.
• D when used in conjunction with FFP shows the mask has undergone the additional Dolomite Clogging Test and as a general rule this indicates a better resistance to clogging of the medium filter.

 

I know this is a lot to take in and there's a lot more to come, but it is incredibly important that the correct RPE is selected for the task and hazard at hand. This is only the beginning, in future posts we're going to cover topics such as the maintenance of RPE, determining the assigned protection factor required, what the law has to say, carrying out a fit test and training.

I hope this post has been useful we'll see you again soon.

 

Danny