Hazardous substances

Hazardous substances

Some chemicals and substances that are used at work, or are a by-product of work process, can damage your health, sometimes seriously. These substances can come in a number of forms, ranging from dusts and gases that can be breathed in, to liquids that can come into contact with your eyes or skin.

Most businesses use substances that can damage your health. Sometimes substances are easily recognised as harmful, such as paint, bleach or dust. But others are less obvious.

According to the TUC, between 15,000 and 18,000 people die of cancer each year because of previous exposure to chemicals at work, while a further 30,000 to 40,000 people develop cancer annually. Thousands more people die from other conditions caused by past exposure to hazardous substances.

Ill health caused by these substances used at work is preventable. Many substances can harm health but, used properly, they almost never do.

Hazards and health conditions

Exposure to hazardous substances can cause range of diseases and conditions. Some might develop quickly, while others take years to develop. The nature of these conditions will depend on the substance, the form that it is in and the duration of exposure, but they can include:

  • Cancer of all organs of the body
  • Reproductive disorders
  • Nerve and brain disorders
  • Heart, lung, liver and kidney diseases
  • Skin diseases
  • Allergies, sensitisation and irritation of the eyes, skin and the respiratory system.

Hazardous substances come in a number of forms, including

  • Chemicals, or mixtures of chemicals, such as bleach, acid, solvents or adhesives (which can come in a number of forms)
  • Fumes or gases, such as those produced by welding or soldering, chlorine, carbon monoxide, paints or inks
  • Liquids or mists, such as those used in metalworking, solvents, cleaning chemicals, even water
  • Dusts, such as respirable crystalline silica, wood, flour, cement or metal
  • Biological agents, such as fungi, bacteria and viruses

Exposure can occur through four routes, depending on the form of the substance: inhalation; skin or eye absorption; injection and ingestion.

What your employer should do

The main regulations governing how employers manage harmful substances are the Control of Substances Hazardous to Health Regulations 2002, often abbreviated to the COSHH Regulations. They cover all substances that can damage your health.

The COSHH Regulations do not cover work with asbestos, lead or radiation because these substances are governed by their own sets of regulations.

Much like other health and safety regulations, COSHH requires employers to either prevent exposure to hazardous substances altogether or, where that is not possible, reduce it to as low as is reasonably practicable.

Employers must carry out a COSHH risk assessment, and implement the controls it identifies, before employees start work with any hazardous substance. This COSHH risk assessment must consider:

  • the processes that involve or create hazardous substances
  • how these cause harm, and
  • how this harm can be reduced.

To gauge how dangerous processes are, employers will need to gather information on the substances. This can come from a variety of sources, such as the HSE, the internet or suppliers. Chemical products should be supplied with a safety data sheet. This document describes the hazards the chemical presents, and gives information on handling, storage and emergency measures in case of accident.

Employers must work out if it is possible to eliminate the risk. This could include substituting a hazardous substance with another that presents less, or no, risk; or adopting a different work process which doesn't create a hazardous form of that substance.

If it is not possible to eliminate the risk, steps should be taken to reduce exposure. This might involve enclosing the work process so that fumes cannot escape; installing a ventilation system, which extracts dust or gases; or introducing methods of work – operating procedures, supervision and training – which mean the process isn’t as dangerous.

Personal protective equipment, like masks or gloves, should be used only as a last resort if other methods of reducing exposure cannot adequately control the risk. This is because if it fails, for example if it is not worn correctly or it breaks, it will offer no protection.

Different substances will require employers to take different steps, but the overarching principles are the same regardless of the substance.

In some cases, employers have to monitor the health of employees who work with hazardous substances. This is to check whether the steps they are taking to reduce exposure are effective. This is necessary if there have been previous cases of work-related ill health in the workplace or industry; or where there is still some risks posed by the hazardous substances, despite the steps taken to reduce them.

Employers must tell workers about the hazards and risks of any substances they are required to work with, and how to keep themselves safe.

For some substances, the HSE has established what is known as a “workplace exposure limit”, often abbreviated to WEL. These are maximum concentrations of substances in the air, averaged over a period of time. They are intended to prevent excessive exposure. These WELs provide an additional layer of legal protection to the steps outlined above, and must be complied with. However, it is usually possible for employers to reduce employees’ exposure beyond them. When it is, employers must do so.

What you can do

  • Report defects and failures in the control measures to your employer or your safety rep
  • Remove any clothing or PPE which could cause contamination before eating or drinking
  • Make use of washing facilities
  • If you’re a safety rep and concerned about your employer’s control of hazardous substances, ask to see their COSHH risk assessment.

Further reading