Welding fumes and metalworking fluids pose occupational safety risks to those who work for fabricated metal businesses. In the UK, employers must protect their workers from welding fume health risks by law. This applies to everyone who welds, no matter how often or for how long.
All welding fumes can cause lung cancer, so it's important to control them.
Welding fumes are covered by the Control of Substances Hazardous to Health (COSHH) regulations. For more information about what COSHH requires of employees, see COSHH: A Comprehensive Guide.
In this article, we will answer some frequently asked questions specifically about welding fumes and metalworking fluids and the risks associated with them.
What are welding fumes?
Welding is a common process used in fabricated metal manufacturing. Welding fumes, including those generated from processes like plasma cutting, are tiny particles that form when the base metal is heated during welding. During the welding process, a piece of metal is heated to a temperature above its melting point, causing parts to evaporate and condense into fumes. These particles can float in the air for a long time.
The type of particles depends on the metal being welded and any coatings on it. For example, welding iron or steel mostly creates iron oxide fumes.
Are welding fumes toxic?
Yes, welding fumes can be harmful. They can cause both short-term and long-term health problems.
Short-term effects:
- Gases like carbon monoxide and nitrogen dioxide can be dangerous, especially in confined spaces
- These gases can irritate the eyes, nose, and throat
- In extreme cases, they can lead to breathing difficulties
Long-term effects:
- Occupational lung disease, including lung cancer
- Occupational asthma
- Other respiratory illnesses
Gases, such as carbon monoxide and nitrogen dioxide, are produced when welding. Exposure to these gases is dangerous, especially in the welder’s breathing zone, as carbon monoxide can cause asphyxiation by affecting the body’s ability to carry oxygen in the blood, and nitrogen dioxide can irritate the eyes, nose, and throat upon contact. These gases are particularly dangerous when working in a confined space, as they can build up quickly and create an oxygen-deficient environment.
The most common long-term health risk associated with exposure to welding fumes is occupational lung disease, including lung cancer, but it can also lead to the development of occupational asthma and other respiratory illnesses.
How can people be protected from inhaling welding fumes?
Health and safety law requires employers to put control measures in place to protect workers from the risks posed by welding fumes.
Here's a simple breakdown of what employers need to do:
- Try to avoid or reduce exposure:
- Can you use a method that makes less fume?
- Is it possible to automate the welding?
- Could you use different materials or processes?
- Use local exhaust ventilation (LEV):
- This is a fume extraction system that removes the fumes
- A fume extractor is much better than a fan, which can spread fumes around
- Provide proper breathing protection:
- Use this when local exhaust ventilation systems are not enough or cannot be used
- Make sure to choose the right type for the job
In situations where fume extraction solutions are not possible, or if there is still a significant risk of worker exposure with a system in place, high quality respiratory protective equipment (RPE) must be provided to prevent inhalation of harmful fumes. Masks should be equipped with a suitable filtration system for effective extraction of particles. Additionally, a portable solution for ventilation may be necessary for some tasks.
The specific kind of equipment used will vary depending on the task and its duration. The Health and Safety Executive has produced Welding Fume Control Guidance that provides more information.
What are metalworking fluids?
Metalworking fluids are used during the creation of fabricated metal products for many reasons, including to provide lubrication and cooling, to carry away debris and to improve performance. They are typically applied by continuous jet, spray or hand dispenser, and are often referred to as:
- Suds
- Synthetic fluids
- Coolants
- Cutting fluids
- Slurry
- Soap
Are metalworking fluids dangerous?
Metalworking fluids are hazardous substances that can affect those working with them in several ways. They can be inhaled by those working around them, come in contact with skin if suitable personal protective equipment is not used and enter the body through cuts, abrasions or the mouth.
Exposure to metalworking fluids can result in several health effects, including skin disorders such as dermatitis and respiratory conditions that include work-related asthma, bronchitis and occupational hypersensitivity pneumonitis. This is the case because the oils and metal debris found in metalworking fluids can irritate the skin and respiratory tract. Also, harmful bacteria and fungi can grow in fluid systems that contain water or water mixes.
What needs to be done to protect people from metalworking fluids?
Similarly to welding fumes, health and safety law requires employers to put measures in place to protect their workers from the dangers posed by metalworking fluids. The extent and form of these measures will depend on the specific fluids and processes used but may include installing splash guards, regulating the volume and rate of the fluid’s delivery to minimise vapour production and providing suitable personal protective equipment (PPE) to prevent skin contact.
There are also several measures that workers can take to protect themselves from the risks posed by metalworking fluids, including eating and drinking in designated areas away from any fluids, washing their hands thoroughly before and after working with them and regularly changing dirty overalls.
What is health surveillance?
Health surveillance is a process in which an employer regularly checks the health of its employees, and is required if indicated in a risk assessment. This process will vary depending on the specific risks that the worker is exposed to and is important to protect workers’ health because it helps to spot health changes and signs of disease early.
Who needs to complete health surveillance?
Asthma health surveillance should be provided for workers who are regularly exposed to welding fumes that include asthmagens (substances that can cause asthma), such as those generated when welding mild steel and stainless steel with a welding torch, which produces hexavalent chromium. Additionally, exposure to manganese from welding fumes may pose other health risks. It may also be useful to maintain health records for everyone who works around all forms of welding fumes regularly because it is carcinogenic by nature. Also, regular skin and breathing inspections should be carried out on those who work with metalworking fluids.
What training do metalworkers need?
To protect metalworkers from harm, they must receive training that makes them aware of the dangers associated with welding fumes and/or metalworking fluids. This is especially important for those who are new to metalworking.
This training should also cover topics such as how workers can safely carry out their duties, how to use any risk control measures in place and how to identify any health problems that they may experience.
The HSE provides advice on how to manage the risks associated with welding fumes and metalworking fluids. Those who work with these substances should also consider taking our COSHH Awareness course:
