What Is COSHH? Hazardous Substance Control Explained

Every business — regardless of size or industry — must comply with health and safety laws. And for most businesses, the COSHH Regulations play a big role in health and safety procedures. If you’re not sure exactly what COSHH is or how to comply with these regulations, here’s everything you need to know. 

What Is COSHH?

COSHH is short for “Control of Substances Hazardous to Health”, a set of health and safety regulations. Under these regulations, businesses are required by law to protect workers from potentially harmful substances.

Regardless of which industry your business operates in, the chances are the COSHH regulations will apply to your company. Even businesses in the least dangerous industries will use substances that could be harmful to employees. For example, everyday products, such as cleaning agents, can be considered hazardous. 

So employers must take steps to monitor and manage risks, implement control measures and keep exposure to hazardous substances to a minimum.

Why Are the COSHH Regulations Important?

Last year alone, 1.4 million workers in the UK suffered from work-related ill-health. Many injuries and medical conditions, including lung disease and skin cancer, were caused by exposure to dangerous substances. COSHH aims to keep employees out of harm’s way and reduce the number of work-related injuries and health conditions across the UK. 

Breaching these regulations puts your workers at risk of harm and ill-health, and non-compliance is also a crime that could result in prosecution. So if you employ anyone who might come into contact with hazardous substances, it’s essential you fully understand the COSHH regulations and how you can comply and keep your workforce safe from harm. 

What Is a Hazardous Substance? 

Before you can meet the COSHH requirements, you need to know what substances to protect your workers from. Substances can take different forms, including:

  • Chemicals
  • Fumes
  • Dust
  • Vapour
  • Mist
  • Nanoparticles 
  • Gases
  • Fibres
  • Germs (bacteria and viruses)

Any substances with the potential to cause harm are hazardous. They may be classed as an irritant, a corrosive, toxic or health hazard depending on the danger they present. Dangerous substances can cause health issues when they come into contact with skin or eyes, when they’re inhaled, swallowed or injected. While it’s unlikely your employees will be injecting dangerous substances, they can enter the body’s bloodstream through cuts and open wounds. 

Other types of hazardous substances include lead, asbestos and radioactive elements — but the COSHH regulations don’t cover these. That’s not to say businesses shouldn’t protect their employees from these materials — the only reason the COSHH doesn’t include these substances is they have their own specific regulations that you need to follow. 

What Are the COSHH Symbols? 

coshh symbolsHazardous products are labelled with the relevant COSHH symbols. These indicate how a substance is dangerous and cautions users. COSHH symbols are international, so they’re recognised, understood and used in countries all over the world. 

There are nine COSHH symbols. While some are self-explanatory, others might require an explanation — especially if you haven’t come across them before. Here’s a brief description of some of the not-so-obvious COSHH symbols: 

  • Oxidising: These substances interact with other chemicals and may cause a fire or explosion. Common oxidising substances are oxygen, hydrogen peroxide and halogen elements.
  • Compressed Gas: This indicates the gas is stored under pressure. Many people overlook the dangers of compressed gas, but it can be a very hazardous substance. If compressed gas is heated, or the tank isn’t properly maintained, it may explode. Refrigerated compressed gas can cause cryogenic burns if it comes into contact with the skin.
  • Corrosive: These substances will destroy living tissue and other substances when it comes into contact with them. It can damage materials and cause severe burns and eye damage.
  • Toxic: Toxic materials can damage a person’s health — even at low levels of exposure. If a toxic substance comes into contact with skin or is inhaled, it may be fatal. Examples of toxic substances include mercury and chlorine gas.
  • Health Hazard: This symbol is also known to mean “long term health hazards”. This symbol indicates that a substance might cause serious health issues such as damaged organs, cancer and genetic defects. 

How to Comply with COSHH Regulations

Identify and Assess Risks

The first step to complying with the regulations is a COSHH risk assessment. This involves identifying and assessing hazardous substance risks in the workplace.

Often, products will contain labels with COSHH symbols indicating whether or not they’re hazardous. However, identifying harmful substances isn’t always as easy as spotting labels on products. You will need to walk around your workplace to identify hazards, consider any equipment that might produce hazardous substances and consult the HSE web page for your industry to find examples of dangerous substances to consider. 

Once you have identified risks, you will need to record how these substances might cause harm, how likely they are to cause harm and the jobs or tasks will lead to exposure. 

Prevent Exposure to Hazardous Substances 

Preventing, or at least reducing, exposure to hazardous substances is one of the main requirements of the COSHH. Controlling exposure to hazardous materials can make your workplace a safer place, preventing accidents, injuries and work-related ill-health. As an employer, you are responsible for implementing control measures to prevent or reduce your employees’ exposure to risks. Here are some of the steps you must take to avoid exposure:


  • Substitute Dangerous Substances
    One of the best ways to prevent exposure to hazardous substances is to consider alternative substances that present less risk.
  • Use Control Equipment
    Control equipment includes ventilation systems, extraction systems, Personal Protective Equipment (PPE), and decontamination equipment. Such equipment can reduce exposure to airborne hazards such as chemicals, germs and dust, reduce the risk of contamination, and prevent accidents when handling or working with dangerous substances. 
  • Provide Personal Protective Equipment
    Sometimes working with hazardous substances is unavoidable, but in such cases, you should provide, replace and pay for any personal protective equipment employees need to stay safe while working. Types of PPE include respirators, protective gloves, clothing, footwear and eyewear. You are responsible for making sure the PPE effectively protects employees from any harm.
  • Supervision
    Supervision can prevent accidents involving hazardous substances. Supervisors must ensure health and safety procedures are followed and offer advice when it comes to handling or working around dangerous substances. 

Monitor the Control Measures

Once control measures are in place, the COSHH requires employers to monitor how effective these measures are. Methods of monitoring can include recording any accidents or injuries that occur despite control measures, testing for bacteria on surfaces, and monitoring air quality.

If your control measures prove successful in reducing or preventing exposure to harmful substances, you can show you’ve taken the necessary steps to minimise risk. Regular monitoring will also help you make sure your control measures stay up to date and relevant. 

Monitor Employees’ Health 

As well as monitoring the control measures around the workplace, you may choose to keep an eye on your employees’ wellbeing with health surveillance. Health checks, tests, examinations and questionnaires can provide data about employees’ health and can help you detect and evaluate health hazards and control measures. 

For some employees, health surveillance is a legal requirement — if employees are frequently exposed to health risks, you should monitor their wellbeing. But even when health surveillance is optional, it can be a good idea to collect valuable information about how employees are affected by the work environment. 

Provide Training about Hazardous Substances

It is your responsibility as an employer to provide training and information for your employees about hazardous substance control. Employees should have access to the COSHH risk assessment, information about what the workplace hazards are and training on how to stay safe when working with hazardous substances. 

As well as ensuring employees have up-to-date knowledge of COSHH health and safety risks and procedures, you must also make sure any on-site contractors know the risks and how you are controlling them. 

Prepare for Accidents and Emergencies 

While the COSHH aims to prevent accidents from occurring, you will need to have a plan in place for dealing with foreseeable accidents and emergencies. You’ll need the right equipment, procedures, and people on-site to deal with emergencies such as casualties and spills of hazardous substances. If dangerous products are spilt, you will also need to have arrangements in place to deal with any waste created, to prevent this from causing any further accidents. 

COSHH Employee Responsibilities

Most of the COSHH requirements and responsibilities fall on employers.  However, employees can share some of the responsibility by making sure they follow health and safety procedures and implement COSHH control measures. 

Employees should keep up to date with provided training and information regarding risk management and carry out tasks with risk prevention in mind. They must use any control equipment provided — such as PPE —  where necessary and should take responsibility for keeping the workplace clean and free from germs. As well as ensuring their own safety, employees can also help colleagues and contractors stay safe when working with hazardous substances.

The CHAS Common Assessment Standard makes it easier for both clients and contractors to achieve compliance. Once a year, a CHAS assessor will review your information and make sure you’re compliant with risk management regulations, including Health and Safety and COSHH regulations. Sign up for a CHAS Premier Membership today and secure accreditation for your company. 

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