A few days ago (February 2019), the health and safety executive (HSE) issued bulletin STSU1 – 2019.  The bulletin explains that new scientific research has linked the fumes associated with the welding of mild steel to lung and possibly kidney cancer.  The HSE will now expect that ANY welding conducted in the workplace must have sufficient protection measures from welding fume in place.

“All businesses undertaking welding activities should ensure effective engineering controls are provided and correctly used to control fume arising from those welding activities.” (HSE 2019)

“Regardless of duration, HSE will no longer accept any welding undertaken without any suitable exposure control measures in place, as there is no known level of safe exposure.” (HSE 2019)

A Summary of the HSE changes

Initially I read this and was left wondering the specifics of their “expectations”.  As a welding supplier and supplier of welding fume extraction systems, I was keen to make sure our company was knowledgeable of the new guidance and make sure we supplied the correct equipment and advice.  It got me thinking of the impact it will have on businesses, increased end user costs and increased control measures in the work place.  Below is a summary of information found on the HSE website which may help employers and business owners understand the requirements of the HSE for welding in the workplace. 

I have also sought clarification from HSE and spoke in length with their lead on the subject, the Head of Metals, Minerals and Engineering Sector.

What are Engineering Controls?

In no uncertain terms, engineering controls refer to localised exhaust ventilation (LEV).

“Make sure exposure to any welding fume released is adequately controlled using engineering controls (typically LEV)” (HSE 2019)

It seems that LEV refers to down draft welding benches, mobile fume extractors with arms and MIG torch extraction.

The British Occupational Hygiene Society (BOHS) have launched a website which includes a tool to help guide what control measure an employer can take against the fume created by a welding process.  The Welding Fume Control Selector Tool asks a number of questions and based on the answers, provides an optimum control

Are there Exceptions to LEV?

As mentioned above, I have spoken in length with the HSE about this subject and the expectation is clear – extraction MUST be used when undertaking any welding in an inside environment.  If extraction leaves residual fume, respiratory protective equipment (RPE) should also be worn. 

Otherwise, it is down to the employer to document the reason as to why extraction would not be suitable.  When asked, the Health and Safety Executive could only think of situations such as working at height or when there are access issues where LEV would not be applicable.  In these situations, RPE may be deemed suitable but consideration would also need to be given for other persons in the area.  Variables to consider in these circumstances – fume clearing times, ventilation, restriction of access to the area or RPE despite of persons in the area.

The other exception is outside welding.  In these instances, LEV is not practical nor is it effective.  Any welding conducted in an outside environment must be conducted with the use of RPE, whether that be air fed helmets or face fit respirators.

 “Battery powered filtering welding visors are more expensive but are good when it is not practical to use extraction and the welder is doing a reasonable amount of welding” (http://www.hse.gov.uk/welding/fume-extraction-rpe.htm – 2019)

Masks and Air Fed Masks are they Enough?

The law states that RPE, (Respiratory Protective Equipment) whether that be powered air or face fit masks are NOT deemed to be suitable as a standalone control measure in inside environments against welding fume unless:

  • for emergency work or temporary failure of controls where other means of control are not reasonably practicable
  • for short-term or infrequent exposure, such as during maintenance work, where you decide that other controls at the source of the exposure are not reasonably practicable. (HSG53 2013)

“The laws governing the control of harmful substances in the workplace, and their supporting ACOP (Approved codes of practice), say that you should only use RPE after you have taken all other reasonably practicable measures to prevent or control exposure. By going through the risk assessment process required by these laws, you can determine whether the use of RPE is necessary in your workplace. If you write your justification for using RPE on your risk assessment record you should remember the reasons behind your chosen control regime and be able to adapt it in the future as necessary. If you have fewer than five employees you are not legally required to record your risk assessment.” (HSG53 2013)

If RPE is to be used in the workplace, the HSE guidelines state:

  • The mask should be correct for the job ie correct levels of filtration. 
  • User must be clean shaven (when using face fit masks)
  • Should be stored correctly
  • Filters/masks should be replaced as per manufacturers guidelines
  • Masks should be face fitted to the user – different masks fit different face types

More information on RPE can be found at http://www.hse.gov.uk/pubns/priced/hsg53.pdf

Information about LEVs

An LEV, or Localised Exhaust Ventilation is an extraction system which is generally a mobile unit with a ducting arm.  The articulating arm can be used to direct the extraction hood over the area generating fume.  Fume is sucked up the ducting into an air filtration system and is then expelled as clean air back into the environment.  LEVs are available with one or two arms and with either disposable or re-useable filters.  Whilst an LEV with disposable filters is cheaper to purchase initially, a re-useable filter machine offers lower long term running costs.  Extractors with re-useable filters often have connections for a compressed air system to use pulses of air to clean the filters. 

In large workplaces a large filtration unit would feed ducting leading to multiple extraction hoods over different work areas.

Spark arrestors should be included within the machine for any application where hot sparks or spatter are produced.  The spark arrestor prevents the hot material from entering the combustible filter and prevents fire hazards. 

LEV units should be maintained correctly with filters being changed at manufacturers recommended intervals.  The LEV should also be used correctly to ensure fume is extracted efficiently.  Guidance for LEV maintenance can be found at the following URL:  http://www.hse.gov.uk/pubns/priced/hsg258.pdf

Bottom Line

From researching the HSE website, I found lots of information which didn’t provide a black and white answer to the HSE expectations.  Having now spoken with the Head of Metals, Minerals and Engineering Sector it is now clear:

  • Extraction MUST be used unless practically not possible when welding indoors regardless of material or duration.
  • RPE can be used as a secondary line of defence to protect against residual fume or for outside welding environments.

This article is meant as a guide only and does not substitute advice given by the HSE.  Please see the HSE website to ensure the correct control measures are used within your work place.  Should you require extraction systems or air fed welding helmets, TBWS can assist.