What is COSHH? A Step by Step to COSHH Assessments

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What does COSHH stand for?

COSHH  stands for the Control of Substances Hazardous to Health.  It is the set of guidelines first introduced in 1988, outlined out by the HSE to ensure any business using hazardous substances, do so in a controlled and safe way. This aims to reduce accidents and risk to health of employees in the workplace.

It’s important that all businesses, even those individuals who are self employed take the necessary steps to protect themselves.

COSHH applies to all industries using harmful substances and this can include catering, baking, beauty and hairdressing, cleaning, agriculture, engineering, motor vehicle repair and so on.

This guide will cover the following 8 Steps of COSHH:

  1. COSHH Risk Assessment
  2. Precautions
  3. Prevent or control exposure
  4. Maintenance of control measures 
  5. Monitor exposure
  6. Health surveillance
  7. Plans & procedures for accidents and emergencies
  8. Training for employees

Additional Resources

Why do I need COSHH?

The purpose of COSHH is to protect the well-being of your employees, which is required by law.

It guides you through evaluating the risks in your business, to how you can best control or prevent them. Health monitoring, assessment of procedures and equipment should be undertaken regularly to ensure you uphold your compliance with COSHH.

Most businesses will work with some substances which pose a risk to health, even products such as mild cleaning agents can be hazardous to employees if not used correctly.

Step 1. COSHH Risk Assessment

The risk assessment aims to identify all harmful substances which can damage health and the tasks where there is exposure to these materials.

COSHH Risk Assessment

Identify who should carry out your assessment

Employers may carry out the assessment themselves or delegate to a member of staff who has the knowledge and experience.

This could include qualifications, practical experience of the circumstances and any training in occupational hygiene. Be mindful that how extensive their abilities need to be, will depend on the individual risk or situation.

If you don’t have the necessary skills in house, enlist the help of expertise from outside your business.

Your risk assessment will need to include:

  • Identifying and listing all hazardous substances in the workplace – they may not always be labelled as harmful
  • Evaluating the implications to health of each substance
  • Assessing who may be affected and how
    • Don’t forget to think about contractors or anyone else who could be exposed.
    • Exposure routes include – by breathing in dust, gas or mist, by skin contact or by swallowing
  • Record all your findings

Risk Assessment Helpful documents

  • Tips on how to assess harmful substances

You do not necessarily need a qualification to carry out a risk assessment, however the basic skills required are outlined here by the HSE.

For detailed information on how to write a COSHH risk assessment view the following guidelines.

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Step 2. Precautions

If you identify risks from your initial assessment, you should review precautions you can take to remove the risk or whether it’s possible to change internal processes.

Ask yourself:

  • Can we use an alternative?
  • Can we change our process to eliminate the hazardous substances?
  • What control measures do we already have in place & do they work?

You should compare any control measures you have already with the following:

Think about  the necessary precautions you need to take to protect your employees. If you can’t eliminate the hazard, controlling exposure is crucial.

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Step 3. Prevention or Adequate Control of Exposure

If you can’t eliminate the risk, control measures should be put in place for each risk based activity you identified in your assessment.

Here are some examples of what you need think about when putting these measures in place.

  • What processes, systems or engineering controls can you use that minimise the amount of hazardous material used or produced?
  • What equipment can you use that completely isolates the hazard?
  • How can you control the exposure at the source? Can you implement a ventilation system which extracts fumes?
  • Establish how the substance should be stored. Does it need to be segregated, kept in a locked cabinet or at a particular temperature?
  • How could the substance be absorbed? What personal protective equipment do you need? This should be used in conjunction with other safety methods and not as a replacement.

Helpful Documents

  • Chemical Segregation
  • Storing hazardous substances in the workplace

Your control measures will depend entirely on the hazard itself. Adequate control under COSHH means:

  • Apply the 8 principles of COSHH
  • Do not exceed the WEL (workplace exposure limit)
  • If the substance causes cancer, heritable damage or asthma, reduce exposure to as low as reasonably possible.

Page 29 of the HSE guide provides details on adequate control including how to  use, store, label and dispose of dangerous substances. Available to download here.

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Step 4. Maintenance of Control Measures

COSHH requires that you maintain your controls so they perform to the standard in which they did when they were initially introduced. You will need to:

  • Train employees on how to use control measures
  • Ensure they are aware of how to report problems
  • Regularly check procedures and equipment

This will involve making sure any protective clothing, equipment or systems are regularly tested and perform to the original standard.[wpanchor id=”#monitorexposure”]

You must retain your records of all tests and examinations carried out for at least 5 years.

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Step 5. Monitoring exposure

To comply with COSHH you need to measure the concentration of hazardous substances in the air which could be breathed in by workers, where your risk assessment has concluded that:

  • Exposure limits may be surpassed
  • Control measures aren’t working properly
  • There is a serious risk to health if control measures fail

Before monitoring, you should be familiar with the exposure limits. A WEL (workplace exposure limit) is the maximum concentration of an airborne substance over a specified time period, to which a person can be exposed.

There are 2 forms of monitoring airborne substances:

  • Personal monitoring – this establishes the concentration of an airborne substance within an employees breathing zone. The sample should be taken from the breathing zone around the employee’s face.
  • Fixed place monitoring- can be at the source of emission, or another area of the workplace away from the hazard – this can help determine if your control measures are effective.

You need to keep and maintain any records of exposure monitoring you carry out and allow employees access to their personal record.

For detailed information on monitoring strategies of harmful substances, review the HSE guide to monitoring toxic substances.

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Step 6. Health Surveillance

After taking the steps outlined above, it will be apparent where some risk remains. If the risk remains where:

  • An employee is exposed to one of the substances listed in medical surveillance schedule 6 (page 92).
  • An employee is exposed to a substance linked to a disease, and it is likely, due to work conditions that this disease could occur.

Health surveillance should be a regularly planned assessment and health records need to be kept for at least 40 years.

The surveillance may involve:

  • Examining an employees skin for conditions such as dermatitis
  • Assessing their breathing, where work may involve substances causing asthma
  • A health assessment to identify any disease which could appear when using a particular substance.

Assessments should be carried out by an occupational health service physician or GP who is competent in occupational medicine.

The HSE provides various guidelines on surveillance for different circumstances.

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Step 7. Creating Plans and Procedures

In the event of an accident or emergency, you need to have the necessary processes in place to handle such a situation.  This involves planning for an emergency whereby the exposure to dangerous substances goes far beyond day to day contact.

You will need to:

  • Plan and set up warning and communication systems
  • Ensure all information is available to those who should be aware – this may include emergency services.
  • Practice safety drills with all staff regularly
  • Have a plan in place which outlines the steps involved to reduce the harmful effects, restore the situation to normal and inform employees who are affected.
  • Ensure you have the necessary safety equipment.

The above must be complied with in full where carcinogens, mutagens or biological agents are used.

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Step 8. COSHH Training

All employees need to be properly trained and provided with the relevant instructions. You are responsible for ensuring they are fully trained on the following:

  • Access to safety datasheets
  • The names of the substances they work with and the risks to health
  • The findings of your risk assessment
  • Precautions they need to take to protect themselves and others
  • How to properly use the PPE clothing they’re supplied with
  • Results of exposure monitoring and health surveillance
  • Fully understanding control measures and how to report faults
  • Emergency procedures

This information and employee training should be reviewed and updated when necessary.

If any changes occur to the type of work, method or substance used, you will need to undergo the steps outlined in this guide; then the relevant documentation and training should be updated.

If you would like advice on training for employees, please review details on the HSE website here.

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