Respiratory Protection Chris Coombs 21st Feb At this point put on existing P3 AURA mask

Dust and Particulates Dusts are formed by the mechanical breakage of a parent material, down into smaller particles, usually larger than 0.5 microns. Dusts can be formed by: Drilling Crushing Grinding Sanding Milling Sweeping The smaller the dust, the longer it hangs in the air and the easier it is to inhale. Other forms of particulate: Mist, Weld Fume, Smoke, Aerosols, Fibres etc

Our defence mechanisms have problems with the following: Introduction Limitations of the respiratory system’s defences… Our defence mechanisms have problems with the following:  Large quantities (Can swamp our defences) Toxic, poisonous or infectious particles (Can damage our lungs as well as other parts of the body)   Sensitising particles (Can trigger allergic reactions e.g asthma) Very small particles (Can bypass most of our defences to reach the lungs)

Introduction Filtration by the respiratory system 30 – 5 µm diameter particles are filtered out here 5 – 1 µm diameter particles are filtered out here Particles less than 1µm diameter can reach the lungs

Hierarchy of controls Elimination – Physically remove the hazard Substitution – Replace the hazard Engineering controls – Isolate workers from the hazards Administrative controls – Change working practises Use of PPE – Protect the worker with PPE Most effective The hierarchy of controls is a universally accepted system used throughout industry to minimise or eliminate work-place exposure to hazards – including respiratory hazards. The hierarchy details a range of controls, in their order of decreasing effectiveness. All too often, PPE and the use of respirators, are seen as the only control and all others are discounted, or not even considered! Personal Protective Equipment or PPE Controls, such as using a respirator, are at the bottom of the hierarchy – the last control that should be considered. PPE and respirators they rely on proper selection and use by the worker – each and every time they are potentially exposed. In other words, the worker is individually responsible. Health & Safety Engineers should work down through the hierarchy, implementing or ruling out each control in turn. However, the use of PPE and respirators is often implemented for various reasons, including: When elimination, substitution, engineering or administrative controls are impractical, uneconomic, impossible to implement, create additional hazards or the implementation of these controls does not fully reduce the hazard to a safe level When other controls are being installed or repaired When emergencies or other temporary situations When mandated by local or national regulations or company policy. In certain circumstances when exposures are beneath limits, but either the employer or the workers desire a voluntary use of respiratory protection Least effective NIOSH Workplace Safety and Health Topic, CDC Hierarchy of Controls, www.cdc.gov/niosh/topics/hierarchy

Respiratory Protective Equipment (RPE) Tight-fitting filtering respirators Before we go on to look at challenges, firstly, what RPE are we looking at? Tight-fitting respirators These come in various forms, but all rely upon a tight seal to the face and the wearer inhaling air through a filter to remove contaminants. Filtering facepiece respirators / Disposable Respirators / ‘dust masks’ – are the simplest type. The filter makes up the body of the respirator. They are typically single use or shingle-shift use only. Reusable respirators can come in different forms: half-masks (covering the mouth and nose) or full-facepieces (covering the mouth, nose, eyes and most of the face). Powered filtering respirators Often known as Powered Air Purifying Respirators (PAPRs), a battery powers a fan that draws in through a filter, the filtered air is fed into either a: Loose-fitting headtop or helmet. These do rely upon a tight-seal to the face to provide respiratory protection. A tight-fitting half or full-face mask Powered systems are portable and flexible, but are limited to battery duration and the capabilities of the fan and filters. Supplied air respirators Similar to powered air respirators, however compressed breathable air is supplied to the wearer by tubing. Like PAPRs, loose-fitting headtops or tight-fitting masks can be used. Supplied air systems can be used where filtration of the ambient air is not possible, difficult or in potential IDLH atmospheres. However, the need to be connected to a compressed air line does limit the workers ability to move around. Self Contained Breathing Apparatus (SCBA) SCBA is significantly more complicated to use and maintain compared to other respirators shown here. Sometimes SCBA is the only option in emergency, high risk or potentially IDLH atmospheres. I am not going to go into the different types of products and their merits in this presentation, otherwise we would be here for many hours. Powered filtering respirators Supplied air respirators Breathing Apparatus (BA or SCBA)

How do Particulate Filters Work? Polypropylene Blown Microfibre Filter

? Mechanical filtration… filter fibres Advanced Electret Filter Material Filter fibres Gaps between filter fibres are larger than the particles Filtration relies on particles making contact with filter fibres ? What’s stopping the particles from bouncing off the filter fibres As a result the gaps between the filter fibres are often much larger than the particles we want to filter out Earlier we mentioned that the four mechanical filtration mechanisms rely on airborne particles in the air making contact with the filter fibres… But what is stopping the particles from bouncing off the filter fibres?

? Mechanical filtration… filter fibres Advanced Electret Filter Material Filter fibres Once a particle touches a filter fibre it will be held there quite firmly by Van der Waal’s forces What’s stopping the particles from bouncing off the filter fibres ?

Assigned Protection Factors Disposable Respirators Protection Levels FFP1: Particulates up to 4x WEL FFP2: Particulates up to 10x the WEL FFP3: Particulates up to 20x the WEL* FFP1 = APF 4 FFP2 = APF 10 FFP3 = APF 20 At 3M we produce multiple different varieties of protection for the respiratory system. We produce valved and unvalved disposable respirators for protection against dust particles and some nuisance level gases, which are categorised into FFP1, FFP2, and FFP3 levels of protection which differ based on the amount of exposure to particles they can protect against. The Nominal Protection Factors are a calculation of the theoretical maximum protection the product can provide. *Workplace Exposure Limit – see HSG 53

Disposable Respirators

Reusable Respirators

Full Face Respirators

These all work on a basic principle? Negative pressure principle Requirement to be Face Fitted Must seal well to face or inward leakage of contaminated air reduces protection

What is fit testing? Means of assessing how well a respirator seals to a face 2 main methods are used: Qualitative taste test Quantitative test using Portacount

Quantitative Particle Counting Test May be used for disposable respirators, half masks and full-face masks with particle filters. Uses TSI Portacount. Facepiece must be probed. Compares particle count inside and outside facepiece. Result reported as a fit factor

Fit test methods – Qualitative Taste Test For disposable respirators and half masks with particle filters. Pass or a fail. Works on the principle of taste. A mist is directed into a hood If there is a leak at the face seal the wearer will taste the solution and fail the test.

Fit Testing Exercises 1 min for each exercise = 7 Minutes

However not everyone can create a Seal? Facial Scarring Adventure Sports ??? % of the population Beard Wearers

Respirators not requiring fit testing Respirators that rely on air flow through the head top and have a loose fit to the face e.g. helmets and hoods – loose fitting