Welding Fume

Welders and others need to be aware that they may be exposed to numerous hazards associated with welding and cutting processes. These include welding fume, fuel gases, inert gases, gas mixtures and solvents.

The short-term health risks of exposure to fume can include:

• Irritation of the throat and lungs including dryness of the throat, tickling, coughing or a tight chest
• Metal fume fever
• Temporary reduced lung function e.g. where breathing is easier when not working

The long-term health risks of exposure to fume can include:

• Cancer including lung and potentially kidney
• Occupational asthma
• Pneumonia
• Bronchitis
• Emphysema

The commonly encountered pollutants in fumes and gases thought to carry the highest risk factors include:

• Ozone
• Chromium particularly in its hexavalent state (Cr6+)
• Nickel (potential carcinogen)
• Cadmium
• Lead

The potential affect to a person of exposure to welding fume depends mainly on the:

• Amount of fume produced
• The pollutants in the fume produced
• The worker's exposure to the fume i.e. time exposed
• The concentration of fumes that a worker is exposed to

Effects may be worsened if an individual has a particular sensitivity (e.g. asthma).

There are many different measures that can be implemented to control exposure to dusts, gases, fumes and vapours in the workplace.

Using the hierarchy of control, we have developed a list of measures in order of priority, each option should be considered starting at the top.

Not all options will be feasible, and, in most cases, more than one measure will be needed.

Risk Assessment

A risk assessment is required to evaluate the risks to a worker from inhaling welding fume. It is used to recommend the elimination of the risk or to substitute the welding technique or consumables. It should consider several factors which would influence how much fume is produced, what pollutants the fume contains, how much fume the welder breathes in and how long the welder is exposed to the fume.

Factors could include:

• The welding process that you use
• The location where the welding is taking place
• The welding conditions
• The length of time that the welder will be creating fume
• The fume control equipment currently available
• The consumables or filler wire that are being used
• The coatings, plating or contamination that are on surfaces being welded or cut

For best practice:

1. Research the base materials and the consumables used
2. Understand the task that you are undertaking
3. Measure the extents of the exposure

Where it is not possible to eliminate or substitute the hazard, control measures should be introduced with the objective of keeping the particulate and gaseous fume levels as low as possible. General ventilation is no longer considered to be adequate as offering the necessary control, the most appropriate engineering control is fume extraction using Local Exhaust Ventilation (LEV).

LEV is an engineering control system which reduces exposures to airborne contaminants such as welding fumes in a workplace by extracting them away from the point of emission. The aim is to capture and remove the airborne contaminant before it enters the breathing space of the worker.

The HSE advises where fume extraction is usually required in the instances below:

• Moderate to high volume MIG/MAG production welding, small or medium sized parts, welding on a bench; or in a screened off area. Welding on carbon (mild) steels and aluminium
• High volume production welding using TIG on stainless steel or aluminium
• Welding of stainless steels using MIG, MAG, Flux cored of MMA (stick welding)
• Arc air gouging
• Welding or hot cutting galvanised materials (zinc plated)
• Welding or hot cutting materials containing cadmium or painted with lead or chromate paints
• Automated cutting (e.g. flame or plasma)
• Automated multi-head resistance welding machines

Visit the HSE website to find out more.

Buying the right LEV equipment is a critical step. Many employers buy LEV equipment to find that it doesn't work. That's because the wrong type has been purchased or because it hasn't been installed or maintained properly.

We offer a range of extraction products including flexible extraction arm and on-torch extraction, but it's important that you select the right equipment. Contact us today to arrange a site survey with our hose team

Contact us on 01482 383288 or email hose.support@arco.co.uk

A flexible extraction arm system has a round or oval inlet at the end of a flexible arm which can be moved over the welding position. The purpose is to draw the welding fume into the capture hood. Suitable filters should be fitted to the units which recirculate the filtered air back into the workplace.

On-torch extraction is only suitable for MIG and MAG welding torches. Extract is very close to the source, so it can be very effective at controlling the fume. An advantage is that extraction will normally be at the optimum position.

LEV should look to remove all welding fumes, where there is obvious visual residual fume or where additional protection is needed further controls in the form of Respiratory Protective Equipment (RPE) such as respirators, air-fed helmets, welding hoods etc. will be required.

Supplied Air

Powered Air Purifying Respirators (PAPR) and Filters

If supplied air is not practical, move to a powered air option

Half-Face Mask and filters

The guidance states that the minimum requirement is an APF of 20 so if you want to add a Gas filter to a Half Mask this would reduce the APF to 10 and therefore wouldn't be suitable. You should instead select a full-face mask.

Full-Face Mask and Filters

For people who are not welding but are in the vicinity we would suggest a P3 welding disposable respirator: 1A2240 10 AlphaFlow Moulded FFP3V Welding Respiratory AMF3CV.

Our Respiratory Protection Technical Specialist can visit your site to advise on the potential risks and hazards and suggest appropriate RPE. If RPE is required, Arco Professional Safety Services can provide face-fit testing for those wearing tight-or close fitting RPE, offer end-user training so equipment is used correctly and ensure equipment is maintained according to specific standards to keep compliance.

Face Fit Testing - Arco Professional Safety Services Fit2Fit accredited mobile respiratory protection team can conduct qualitative and quantitative face fit testing.

Respiratory Training - Arco Professional Safety Services offers individually structured training courses to ensure that your employees understand how RPE works, how to fit and use their specific RPE and aftercare, cleaning and storage.

Servicing and Maintenance - Arco Professional Safety Services help you comply with these requirements by providing services including inspection, maintenance and repair and monthly air purity analysis tests for breathing airline systems.

For advice on Respiratory Training, Maintenance or Face Fit Testing contact Arco Professional Safety Services or Telephone: 0330 390 0822 / Email: info@arcoservices.co.uk

1: HSE - Welding