Frequently Asked Questions

At present we do not have any FAQs for Eyewear Protection but we will update this section as soon as we are launching our new Eyewear range end of March 2007.

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Q. When should Ear Plugs be worn as opposed to Ear Muffs?

A.Many people find ear plugs to be more comfortable to wear over long periods of time. Also, they do not interfere with other types of personal protective equipment (PPE) such as powered respirators. For some frequencies, ear plugs can also offer higher attenuation than ear muffs. To determine the most suitable type of hearing protection, a noise assessment should be undertaken using a sound level meter.

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Q: The 3M 4540 claims to offer protection against nuclear particles. Does this mean that it can be used in all nuclear–related applications?

A: No. The protection against particulate radioactive contamination symbol does not afford protection from radiation. During operations in white zones in nuclear facilities, the 3M 4540 can help prevent radioactive dusts and liquids from reaching the body. However, as some operations may involve highly toxic or corrosive chemicals, protective clothing offering higher barrier levels may be required (consult National Regulations).

Q: Can I use the 4530 or 4540 in asbestos abatement applications?

A: Even though both the 4530 and 4540 offer an excellent barrier to very fine particles (up to 0.1 μ), it is suggested to use a garment with sealed seams (Type 4, i.e. 3M 4560) for abatement as it offers enhanced protection against Asbestos fibres (consult National Regulations for Asbestos Work/Protection).

Q: How do you dispose of the garments?

A: Unused garments can simply be incinerated as household waste. However, contaminated garments must be treated as contaminated waste and disposed of in accordance with national legislation.

Q: What does penetration index mean? Does 0% for a specific chemical mean that nothing can pass through?

A: No. The test as per EN 368 measures liquid penetration through a fabric by simulating exposures to small amounts (10 ml) for 1 minute only. When exposed to larger quantities and for a longer time, considerable percentages may pass through. To determine barrier effectiveness against a specific chemical, please refer to permeation data.

Q: Do permeation data indicate how long a garment can be used?

A: No. Permeation data as per EN369 reports the time taken for a chemical to reach a permeation rate of 1 μg/cm².min. But breakthrough time is not enough. Safe wearer time also depends on the toxicity and behaviour of the substance, as well as exposure conditions and wearer behaviour.

Q: Are accessories such as integrated socks, over sleeves, pockets available from 3M?

A: Yes. The 3M 450 overboot is now available.  Typical applications include: asbestos handling, abbatoirs/farming and pharmaceutical processing. 

This product is an accessory and is not intended for use as Personal Protective Equipment (PPE).  A risk assessment should be carried out by a trained safety professionaal to ensure that appropriate Personal Protective Equipment is selected and worn correctly.

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Q. Why are there APFs and NPFs?

A. A respirator’s Nominal Protection Factor (NPF) is the theoretical protection level based on laboratory measured performance data.

An Assigned Protection Factor (APF), as detailed in BS4275, is the level of respiratory protection that can realistically be achieved in the workplace by 95% of adequately trained and supervised wearers.

The APF should be used when selecting a respirator.

Q. What does the “CE mark” mean?

A. The CE symbol printed on the product/ packaging that informs the market that the product meets the essential requirements of the European directives relating to PPE. It could be described as a ‘passport’ to sell products within the European Union.

The CE mark is not a quality mark and does not indicate the performance of the product.

The product should meet the requirements of a relevant European Standard, e.g. EN149:2001 FFP1. This marking indicates the performance category of the product.

Q. Does a half mask with particulate filters give a higher APF than a similar specification disposable respirator?

A. Purely based on the protection factor, and not taking into account other factors such as user acceptability and cost effectiveness, there is no difference in APF between disposable particulate respirators and a half mask fitted with the same specification filters.

There is a difference between the APF associated with using the same filter on a half mask and a full face mask. e.g. P3 filters on a half mask give an APF of 20 but when the same filters are fitted to a full face mask the APF is 40.

Q. How long does a disposable respirator last?

A. Disposable particulate respirators, tested to EN149:2001, are approved for single shift use. Their effective usage time depends on a number of factors:

• Level of contaminant
• Breathing rate
• Heat
• Humidity
• Hygiene factors

These factors vary from one workplace to the next. For example: an operative working in a very hot, dusty environment may decide to change their respirator at the end of the morning rather than use the same one all day.

Q. How long will my gas/vapour filters last?

A. The life expectancy of a filter will vary from one job to another and is influenced by a variety of factors including the exposure time and location of the job. As long as the hazard has good warning properties, i.e. smell or taste at a lower level than the WEL - HSE publication HSG53 offers additional guidance to users - a filter can be used until breakthrough occurs, however this should not be routinely relied on.

Q. Does MDF (Medium Density Fibreboard) give off Formaldehyde when it is cut or routed?

A. The Health and Safety Executive (HSE) has concluded that machining of MDF is no more, or less, hazardous than working with other forms of wood. In short, formaldehyde is not considered to be a problem.

The HSE has previously suggested that an FFP2 respirator could be evaluated for cutting or routing MDF in ventilated workshops eg. 3M™ 8822 / 9322 Respirators. Alternatively, you could try the 3M™ Powered Air & Airfed Respirators which have the added advantage of providing eye protection & head protection, depending on the model chosen.

Q. What respirator should I use to protect against vehicle exhaust?

A. There is no simple answer to this question as there will normally be Oxides of Carbon and Nitrogen in the mixture of exhaust gases which cannot be filtered out.

The only way to protect against all the contaminants in vehicle exhaust would be with either a supplied air system or self contained breathing apparatus (SCBA). This solution is often not practicable so a compromise solution has to be reached. One option is a 3M half mask fitted with 3M™ 2128 Filters. These filters will filter out fine particulates and offer relief from nuisance levels of acid gas and organic vapours in the exhaust.

Q. Can I use organic vapour filters with isocyanate based compounds?

A. The levels at which isocyanate can be detected by smell or taste are considerably higher than the Workplace Exposure Limit (WEL) as set by the HSE. There would be no indication of smell/taste that 'breakthrough' had occurred until an exposure higher than the WEL.

As isocyanates are a potent occupational asthmagen the safe solution and HSE advice is to use an air fed system which supplies breathable quality air to the wearer rather than filtering out airborne contaminants. The 3M™ Visionair, 3M™ Flowstream or 3M™ S-200 Air Fed Systems could be considered for this type of application.

Q. What respirator do I need when painting?

A. As there are so many different types of paint in common use it is very difficult to suggest one product for everything.

The main problems are vapours from the organic solvent carriers and particulates in the form of pigments and spray mist. In most cases brush or roller applying paint is less hazardous than spraying since a lesser amount of pigment and vapour will become airborne. We suggest the following filter selections for the more commonly occurring paint application groupings:

• Powder coating – particulate filters or supplied air, depending on levels of contaminant.
• Water based – particulate filters often combined with nuisance level organic vapour protection when low levels of solvent are present.
• Solvent based with good warning properties – organic vapour & particulate filters.
• 2-pack isocyanate based – a minimum of a supplied air visor.

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Q: Can 3M Chemical Sorbent be used with every chemical?

A: The 3M Chemical Sorbent can be used with a wide range of liquid chemicals but not all. There are some restrictions that apply, for example, the 3M Chemical Sorbent may not be suitable for cleaning up aggressive chemicals. If in doubt contact 3M or your Emergency Response Co-ordinator in your organisation.

Q: Can 3M Maintenance Sorbent be used for cleaning up mercury spillage?

A: No, because mercury has high density and therefore cannot easily be absorbed. Effective absorption relies on suitable viscosity, the higher the viscosity the lower the absorption.

Q: Which 3M Sorbent can be used for cleaning oil spills on water?

A: The 3M Oil Sorbent because it is hydrophobic and consequently will only absorb oil. The 3M Maintenance Sorbent (although absorbs oil) must not be used for this type of application as it absorbs both oil and water, and the Sorbent sinks to the bottom of water bed.

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Q. Do 3M™ Scotchlite™ Reflective Materials continue to perform even when wet?

A. The answer is simple: "absolutely"!

So committed are we to measure conformance of our products to ensure they exceed all the performance requirements of EN471, the European Standard for High Visibility garments, that we invested in rainfall test equipment, one of only a few units that is commercially owned in Europe.

Housed at our Technical Centre in Bracknell, an in-use test is simulated in the wet 'shower' test. A sample of the material to be tested is placed directly under a flow of water accurately calibrated to a level of 283mm of water per hour. This may not sound a lot until you consider that the Met Office estimates that statistically this level of rainfall occurs only for just two minutes every 1,000 years!

We insist that all our materials far exceed the requirements of the Standard. You can therefore rest assured that they will continue to reflect in even the worst British weather.

Q. What is the significance of having different reflective tape designs on Class 2 High Visibility Waistcoats?

A. There are several configurations of reflective tape permitted for Class 2 garments, due to both the need to have 360° all round visibility of the wearer, and also the need to meet the reflective area requirements of EN471. The two-bodyband and brace configuration offers the highest level of protection as it incorporates the highest degree of 360° visibility of the wearer.

Q. In the event of accidental cutting will the waistcoat continue to protect?

A. No! EN471 specifies minimum amounts of fluorescent and reflective materials for each classification of garment. A garment that has been cut down will not necessarily contain the amounts of these component materials to meet the standard and offer the level of protection afforded by EN471. More importantly the garments will no longer be conforming in line with the level of protection identified as necessary in the risk assessment.

Employers are liable for the safety of their employees and it is their responsibility to equip you with adequate PPE. If you cut down your garment, they will have to issue you with another.

Q. The high visibility garments I have purchased do not contain a label. Is this a problem?

A. If high visibility garments are purchased to protect employees, they are considered to be PPE, which the Work Place Regulations require to be 'suitable for use'. If they do not carry a label featuring the CE Mark, they are not considered to be PPE and therefore cannot be 'suitable for use'. In which case they should not be offered as items that offer high visibility protection.

To find out more about specific Visibility FAQs, please go to our Scotchlite™ Reflective Material website.

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Q: Which respirator do I need when welding stainless steel?

A: When welding stainless steel with MIG or MMA, the welding fumes often contain particles of chromium and nickel, of which chromium is more dangerous to inhale. The 3M™ Adflo™ Respirator with particle filter offers you excellent protection in this application.

TIG welding does not emit much welding fume but creates large quantities of ozone gas. Read more below under ‘When does ozone form?

Plasma cutting and plasma welding give rise to high temperatures, which can emit damaging oxides of nitrogen.

Read more below under ‘What are nitrogen gases?’.

Q: Do I really need respiratory protection when welding ordinary steel?

A: Although welding fume from normal steel is not one of the most dangerous types, it is far from good for your health. Among other things, it contains particles of iron oxide, which can cause siderosis. (chronic inflammation of the lungs).

When welding with MIG/MAG and MMA, there are heavy fume emissions, meaning that both a respirator and good ventilation in the workplace are necessary. When welding ordinary steel, The 3M™ Adflo™ Respirator with particle filter is recommended.

Q: What sort of respirator is needed when welding surface-treated material?

A: When welding surface-treated material, a series of dangerous pollutants can be released; how dangerous depends on the type of surface treatment. When welding galvanised steel, zinc oxide particles are released. These can cause zinc ague, also known as fume fever. If you weld painted material you should be especially careful, as many paints can give off very dangerous air pollutants.

When welding galvanised steel or material painted with lead primer, we recommend that you use The 3M™ Adflo™ Respirator with particle filter. This can be used in  combination with an odour filter to minimise unpleasant odours.

If the material is painted with two component paint or insulated with polyurethane, you should always contact a Safety Engineer. There is a large risk that you will be exposed to isocyanates, which are very dangerous to inhale and difficult to detect. In these cases we recommend a compressed air device like 3M Fresh-air C.

Q: Does shielding gases and alloyed electrodes affect my working environment?

A: When welding with MIG and TIG, the noble gases argon and helium are used as shielding gases. Neither argon nor helium is considered dangerous, but they can displace oxygen in unventilated areas, making the atmosphere oxygen deficient. When welding with MAG, carbon dioxide, or a mixture of carbon dioxide and a noble gas, are used as shielding gases.

Since parts of the shielding gas can be converted into carbon monoxide when the gas reaches the air, large quantities of carbon monoxide can form around the welding arc. Carbon monoxide cannot be filtered away. If the ventilation is poor, the oxygen level must be checked.

Alloyed electrodes are common when welding with MAG. The alloys often contain manganese or silicates. This means that manganese oxide and silicates are diffused into the surrounding air when you are welding. Adflo with particle filter usually offers sufficient protection against alloy particles.

Q: When does ozone form?

A: When welding aluminium not only are particles of aluminium oxide produced but ozone gas is formed by the action of the UV radiation from the arc breaking down molecular oxygen. Ozone is also produced when welding stainless steel with TIG. Eventually ozone will be converted back to oxygen, a process that is speeded up when the ozone comes into contact with solid surfaces that act as a catalyst. Ozone cannot be filtered from the atmosphere but relies on being converted back to oxygen.

At low ozone concentrations the use of the Adflo respirator system with particulate filter reduces the amount of ozone reaching the welder. This is achieved by the fact that the particle filter (because of its large surface area) and the breathing tube to the welding helmet help to catalyse the conversion of ozone back to normal oxygen. At higher concentrations the inclusion of a gas filter in the Adflo respirator adds an additional large surface of carbon granules on which a further reduction of ozone takes place.

Q: What are nitrogen gases?

A: Nitrogen dioxide and nitric oxide are examples of nitrogen gases that are formed when you weld with high amperage and high temperatures. Nitrous gases are formed by a reaction in the air between nitrogen and oxygen and are very dangerous to inhale in large concentrations. Nitrogen gases should not be filtered therefore Fresh-air C is suggested.

Auto-Darkening Welding Filters

Q: Are Speedglas™ Auto-Darkening Welding Filters as safe as traditional shaded glass filters?

A: Yes. Speedglas filters always provide UV/IR protection for your eyes, whether they are turned on or off, dark or light. They're potentially safer than traditional filters and helmets since the Speedglas helmet can always be in the down position, protecting your face and eyes. Plus, your hands are not preoccupied with visor adjustment.

Q: What happens if the battery fails?

A: To repeat: you're always protected from damaging UV/IR radiation. And no matter what, your eyes are always shaded from flash. When you pick up an OFF Speedglas filter, it's intermediately-shaded. When you turn on the filter, it "lightens" and becomes transparent. When an arc is struck, the filter darkens. (The dark shade level depends upon which Speedglas model is used.)

Q: Do you see any of the arc flash?

A: No. The filter changes too quickly for the eye to see a flash. The transition from no arc to arc occurs without a perceptible flash.

Q: Are the Speedglas™ Welding Filters fragile?

A: No more than traditional filters. All Speedglas filters have inner and outer replaceable protection plates. The filter is recessed back into the helmet for further protection. You can treat the heat- and chemical-resistant helmet very much like any other welding helmet.

Q: Why do Speedglas™ Filters and Helmets cost more than traditional filters and helmets?

A: 3M uses state-of-the-art electronics and super lightweight materials to provide the optimum productive, comfortable, and safe helmet/filter combination available. The filter itself is a seven-layer laminate, hand-assembled under clean room conditions, with numerous quality assurance checks. The result is a flawless filter that always lets you see your work.

Q: Are the Speedglas™ Welding Filters compatible with non-Speedglas helmets?

A: No. The high performance and optical clarity of Speedglas filters requires a special design that is not compatible with non-Speedglas helmets. You should never attempt to mix any Speedglas products with non-Speedglas components; doing so may void your product warranty and could result in serious injury.

Q: My shade 11 Speedglas™ Filter appears to be a different dark shade compared to my old conventional filter. Why?

A: Different manufacturers (whether they are making conventional or auto-darkening filters) can have noticeable differences in filter shading, while still conforming to the international safety standards for welding filters. We recommend that you try the shade level you're used to, as well as the models above and below that level (for the above example, try the 10, 11 and 12 shade models). Or go with the Speedglas 9002V or 9002X filters, both of which have user-selectable dark shades of 9, 10, 11, 12 and 13.

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Q. I’ve been told to look on the “MSDS” for some information. What is it and where do I get one?

A: The MSDS or Material Safety Data Sheet is a document published by the manufacturer/processor of a substance that includes information on its usage and handling.
This may include toxicological effects, level of flammability and a breakdown of compounds. Manufacturers are obliged by law to provide a MSDS.

Q. When should I carry out a risk assessment?

A: The simple answer to this question is that you should carry out an assessment when you suspect that there is a risk.
The assessment needs to be of the risks created by the work, not the substances. It is a mistake to think that a risk assessment need only consist of a collection of manufacturers health and safety data sheets. This is often caused by a failure to understand the difference between a hazard and a risk.

Hazard - The potential to cause harm.

Risk - The likelihood that the harm will occur in practice.

A good analogy is a bottle of household bleach. The hazard is the bleach itself, but there is very little risk when the bottle is in a cupboard, but that risk increases if the bottle is left on the edge of a work surface with the lid off.

There is a raft of legislation relating to risk assessment including:

Section 2. Health & Safety at Work Act 1974, General Duties of Employers Employers are required to ensure, so far is reasonably practicable, the health, safety and welfare of all his employees. This does not implicitly mean that you have to carry out a risk assessment, but it would be difficult to comply with the regulation without having assessed the risks.

Regulation 3. Management of Health & Safety at Work Act 1992. A more explicit set of regulations that require risk assessments to be carried out.

Regulation 6. Control of Substances Hazardous To Health Regulations (COSHH). An employer shall not carry on any work which is liable to expose any employees to any substance hazardous to health unless he has made a suitable and sufficient assessment of the risks created by that work to the health of those employees and of the steps that need to be taken to meet the requirements of these Regulations.

Q. How does “Oxygen Deficiency” occur?

A: Oxygen Deficiency occurs when the percentage of oxygen in the air falls below 19.5% (a 3M definition). It can be caused by chemical reaction, fire or when other chemicals displace oxygen from the air. Typically this occurs in confined spaces where there is poor ventilation.

Q. What is meant by “IDLH”?

A: This is the concentration considered Immediately Dangerous to Life or Health (IDLH) as defined by the NIOSH (in the USA). The IDLH concentration is defined as "that poses a threat of exposure to airborne contaminants when that exposure is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from such an environment."
The IDLH value represents a maximum hazard concentration from which a worker would escape within 30 minutes without any escape impairing symptoms or any irreversible health effects.

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