Respiratory Protection

The 3M Four-Step Method What issues do we need to consider to get the correct respiratory protection? 1.Identify Respiratory Hazards 2.Understand the Contaminants Effect on Workers 3.Select the Appropriate Type of Respirator 4.Train in Proper Respirator Use and Care

The Air We Breathe O 2 21% Other gases 1% N 2 78%

The Body s Defenses Cilia Nose hairs Cough Reflex Mucous Blanket

LUNG ANATOMY ~ 300 million alveoli in each lung. Surface area of 140 m 2 ( ~ size of a tennis court). Each alveolus ~ 0.1mm diameter. Each day 8-9,000 litres of breathed-in air meet 8-10,000 litres of blood pumped in by the heart.

Lung Damage Healthy Cilia Damaged Cilia

Lung Diseases Healthy Lung Overexposure to Cadmium Source:Dr F. Netter, Ciba

Lung Diseases Coal Miner s Lung Silicosis Source:Dr F. Netter, Ciba

Asbestos Related Disease Lung Cancer Mesothelioma Source:Dr F. Netter, Ciba

Where Workplace Contaminants can affect Workers

Exposure Standards Airborne concentrations which should not cause adverse health effects for nearly all workers. Exposure Time Concentration Toxicity Breathing Rate Individual Sensitivity

Engineering Controls

Why wear Respirators here? What are the respiratory protection issues in this workplace?

Why wear Respirators here? Knowledge & Evaluation of site specific contaminants. Significant Workplace Exposures - ongoing or emergency (e.g. spills). Exposure Standard/ Regulatory issues e.g. Spraying Isocyanate based paints Confined space entry Oxygen Deficiency

Types of Respiratory Hazards Particulate Dusts Mists Fumes Smokes Gases & Vapours

Sizes of selected particles Visible by electron microscope Visible by microscope Visible by human eye Viruses Unaggregated Welding fume Tobacco smoke Bacteria Industrial mists Pollen Human hair Dust Fog Mists & drizzle Rain 0.01 0.1 1.0 10 100 Particle diameter, microns (1mm = 1,000 microns) 1000 10000 Total Inhalable Range O

Dusts Dusts are formed as solid materials are broken into smaller particles, such as by drilling, crushing or grinding. The smaller the dust, the longer it hangs in the air and the easier it is to inhale.

Mists Mists are tiny liquid droplets usually generated during spraying operations. Many mists are a combination of several hazardous ingredients.

Fumes Fumes occur when metals are heated and then quickly cooled. This creates very fine solid particles that drift in the air.

Filtration Theory for Particle Filters A filter is NOT a screen or sieve. Particles are NOT collected by layering on top of a filter.

Particle filtration

Particle Capture Mechanisms Impaction - Dominant for large particles (>0.6µm) Interception - Operative for particles > 0.1 µm Diffusion - Operative for particles < 0.4 µm, dominant for < 0.1 µm

Electrostatic Attraction Filter fibre Use of charged fibres to improve capture efficiency

Gases Gases are substances that are neither liquids nor solids at room temperature and pressure. Gases can travel far and fast from their source, often undetected,.

Vapours Vapours are substances that evaporate from liquids or solids, for example, as water evaporates to create humidity.

Activated Carbon Carbon derived from coconut shells or coal. Crushed & conditioned at high temps, low O 2 levels. Extensive network of pores & large internal surface areas. Not good at filtering particles!

How much surface area does activated carbon have? 1 kg = 1.1 million m 2 e.g. 2 x 6051 A1 filters hold ~ 140 gms carbon equivalent to 150,000 m 2 OR ~ 30 football fields!

Gas/Vapour Adsorption Residence time in cartridge: ~ 0.1 sec Need FAST reactions for effective removal of toxic gases and vapours. Absorbed Contaminant AIRFLOW

How Long Will My Filter Last? For Particle Filters: Unacceptable breathing resistance Physical damage

How Long Will My Filter Last? For Gas & Vapour Filters this depends on: Contaminant & its Concentration Breathing Rate Relative Humidity Sorbent Capacity

Respirator Selection - Issues to Consider Contaminant Identification Actual Exposure Levels Added Features required: Eye, head, face protection Specific Worker requirements Beards Heat/Cold Task related e.g. welding

Respiratory Protective Equipment Spectrum Surgeon s Mask Half Face or Disposable Respirator Full face Respirator Self- Contained Breathing Apparatus Air- Line Powered- Air Purifying Respirator Increasing Protection

Negative pressure Half face Reusable & Disposable respirators Respirator Types 3 Positive Pressure Supplied Air Systems Powered Air Purifying Respirators (PAPR s) Full face Respirators Self Contained Breathing Apparatus (SCBA)

Use & Fitting Ensure you have the right respirator for the job at hand. Make sure it FITS you! Fitting Instructions should be available. Wear for the entire exposure period. Leave work area if: Damage occurs Dizziness or other distress occurs Irritation occurs Breathing resistance becomes excessive. 3M 2005

Face Fit Issues

Qualitative or Quantitative Fit Testing Methods to determine that an individual can get an effective face fit when using a certain model respirator

Respirator Fitting Maintenance free Type Respirator

Respirator Fit Check Maintenance free Respirator Negative Pressure check Cover mask with hands Inhale Check for air leaks Positive Pressure check Cover mask with hands Exhale Check for air leaks (N.B. Cannot do this check with a valved product)

Respirator Fit Check Negative Pressure check Cover filter inlets Inhale Check for air leaks Positive Pressure check Cover exhalation valve Exhale Check for air leaks

Respirator Misuses

Wear Time If respiratory protection is not worn at all times when exposures occur, protection levels will fall dramatically.

Wear Time Actual Protection Factor with an expected Fit Factor of 100 100 100 X Exp Std Actual Protection Factor 20 10 4.8 9.2 16.8 80 90 95 100 Percent Wear Time

Limitations Check Instructions & Warnings on product packaging. Air Filtering Respirators DO NOT supply oxygen - ensure O 2 levels are >19.5%. Do not modify or alter filters or masks. Ensure filters haven t passed Use-by date. Use in accordance with AS/NZS 1715. User Instructions

Maintenance Check all parts before use Replace defective parts only with genuine replacement parts.

Clean & Inspect your respirator Before cleaning, remove particulate & gas/vapour filters and valves. Wash with mild soap and water. Use a brush to remove dirt Inspect all parts for: Dirt Cracks, tears, holes Distortion Look for: Headstraps breaks, tears loss of elasticity broken buckles/clips Valves Detergent residue cracks, tears, distortion missing covers

Assembling & storing your respirator Air dry all parts. Recheck all parts & replace any defective. Re-assemble the respirator When necessary, discard and replace the filters. Store the clean respirator in a plastic bag or box inside a locker or cabinet.

Storage Location

Summary Respirator Selection Fitting and Use Limitations Maintenance & Storage

3 TechAssist Helpline Yes! You can get assistance & advice on respiratory issues on 1800 024 464

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