COSHH Training Resource

It is recommended to take some notes when reading this resource. The user is unable to partially save the test quiz form and return to it later. The test quiz must be completed in full before submitting.

COSHH – The Control of Substances Hazardous to Health


Every year, thousands of workers are made ill by hazardous substances, contracting lung disease such as asthma, cancer and skin disease such as dermatitis. These diseases cost many millions of pounds each year to:

  • Industry, to replace the trained worker.
  • Society, in disability allowances and medicines.
  • Individuals, who may lose their jobs.

Employers and employees have duties concerning the control of substances hazardous to health in the workplace.

Myth – ‘Of course it’s safe – we’ve always done it this way.’Reality – Some diseases take years to develop. If exposure is high because the task has always been done that way, maybe it’s time for a change.

Which Substances are Harmful?

  • Dusty or fume-laden air can cause lung diseases, e.g. in welders, quarry workers or woodworkers.
  • Metalworking fluids can grow bacteria and fungi which cause dermatitis and asthma.
  • Flowers, bulbs, fruit and vegetables can cause dermatitis.
  • Wet working, e.g. catering and cleaning, can cause dermatitis.
  • Prolonged contact with wet cement in construction can lead to chemical burns and/or dermatitis.
  • Benzene in crude oil can cause leukemia.

Many other products or substances used at work can be harmful, such as paint, ink, glue, lubricant or detergent. Substances can also have other dangerous properties. They may be flammable, for example solvent-based products may give off flammable vapour. Clouds of dust from everyday materials, such as wood dust or flour, can explode if ignited.

Find out what substances are involved that you are working with and in what way are they harmful? You can find out by:

  • Checking information that came with the product, e.g. a safety data sheet.
  • Asking the supplier, sales representative or trade association.
  • Looking in the trade press for health and safety information.
  • Checking on the Internet, e.g. HSE’s website pages for your trade.

Task and Ways of Exposure

Way of exposureTask
Exposure by breathing inOnce breathed in, some substances can attack the nose, throat or lungs while others get into the body through the lungs and harm other parts of the body, e.g. the liver.
Exposure by skin contactSome substances damage skin, while others pass through it and damage other parts of the body. Skin gets contaminated:
– By direct contact with the substance, e.g. if you touch it or dip your hands in it.
– By splashing.
– By substances landing on the skin, e.g. airborne dust.
– By contact with contaminated surfaces – this includes contact with contamination inside protective gloves.
Exposure by swallowingPeople transfer chemicals from their hands to their mouths by eating, smoking etc without washing first.
Exposure to the eyesSome vapours, gases and dusts are irritating to eyes. Caustic fluid splashes can damage eyesight permanently.
Exposure by skin punctureRisks from skin puncture such as butchery or needlestick injuries are rare, but can involve infections or very harmful substances, e.g. drugs.
Myth – ‘It’s natural so it can’t be harmful.’Reality – Natural materials can be harmful. For example, henna can cause dermatitis and asthma, wood dust can cause asthma, stone or concrete dust can cause lung disease such as silicosis, and citrus oils can cause skin problems.

Safety Data Sheets

Products you use may be ‘dangerous for supply’. If so, they will have a label that has one or more hazard symbols. Some examples are given here. These products include common substances in everyday use such as paint, bleach, solvent or fillers. When a product is ‘dangerous for supply’, by law, the supplier must provide you with a safety data sheet. Note: medicines, pesticides and cosmetic products have different legislation and don’t have a safety data sheet. Ask the supplier how the product can be used safely.

Safety data sheets can be hard to understand, with little information on measures for control. However, to find out about health risks and emergency situations, concentrate on:

  • Sections 2 and 16 of the sheet, which tell you what the dangers are.
  • Sections 4-8, which tell you about emergencies, storage and handling.

Since 2009, new international symbols have been gradually replacing the European symbols. Some of them are like the European symbols, but there is no single word describing the hazard. Read the hazard statement on the packaging and the safety data sheet from the supplier.

Hazard Checklist

When assessing if a product or a task has potential to cause harm, ask the following:

  • Does the product you are using have a danger label?
  • Does your process produce gas, fume, dust, mist or vapour?
  • Is the substance harmful to breathe in?
  • Can the substance harm your skin?
  • Is it likely that harm could arise because of the way you use or produce it?

Myth – ‘I don’t work with harmful substances.’Reality – Most businesses use substances that can be hazardous to health – even something as simple as flour can act as a substance hazardous to health.

You should then ask:

  • What are you going to do about it?
  • Should you use something else?
  • Can you use it in another, safer way?
  • Can you control it to stop harm being caused?
  • What measures need to be taken, and when?

Control Measures

Control measures are always a mixture of equipment and ways of working to reduce exposure. No measures, however practical, can work unless they are used properly. So, any procedure should combine the right equipment with the right way of working. This will include instructing, training and supervising the workers doing the tasks.

Myth – ‘What do you expect – it’s a dirty job!’Reality – Why does your job need to be dirty? Think about changing the way you work to produce cleaner processes.

Examples of control measures

Substance, process Control equipment Way of workingManaging
– Cleaning with solvent on rag.  – Use a rag holder.
– Provide a small bin with a lid for used rags.
– Avoid skin contact.
– Reduce solvent vapour from used rags.
– Check controls are used.
– Safe disposal.
– Dust and sparks from abrasive wheel.– Put an enclosure around the wheel and extract the air to a safe place.– Check the airflow indicator.
– Make sure the extraction works.
– Maintain controls.
– Test controls as required by law.
– Fume from cutting
demolition scrap.
– Ventilated welding helmet, gloves.
– Washing facilities.
– Work outdoors upwind of the fume wherever possible.
– Allow the fume to clear before removing helmet.
– Check if there is any lead paint on the scrap being cut.
– Carry out health checks.
– Cutting-fluid mist from a lathe.
– Swarf.
– Put an enclosure around the lathe and extract the air to a safe place.
– Protective gloves.
– Use skin-care products.
– Make sure the extraction works.
– Allow time for the mist to clear from the enclosure before opening it.
– Train workers.
– Check and maintain fluid quality.
– Test controls as required by law.
– Carry out health checks.
– Dust from disc cutter on stone worktop.– Use an enclosure to extract air to a safe place.
– High-efficiency vacuum cleaner.
– Cut and polish worktops inside an enclosure.
– Vacuum up dust.
– Test and maintain controls.
– Carry out health checks.

Myth – ‘They wouldn’t sell it to us if it wasn’t safe.’Reality – Just because something is available to buy, does not mean it is safe – you can buy cyanide for industrial use.

Choosing Control Measures

In order of priority:
1 Eliminate the use of a harmful product or substance and use a safer one.
2 Use a safer form of the product, e.g. paste rather than powder.
3 Change the process to emit less of the substance.
4 Enclose the process so that the product does not escape.
5 Extract emissions of the substance near the source.
6 Have as few workers in harm’s way as possible.
7 Provide PPE equipment such as gloves, coveralls and a respirator. PPE must fit the wearer.

Control Equipment

Control equipment comes in many forms. It includes ventilation to extract dust, mist and fume; glove boxes and fume cupboards; spray booths and refuges (clean rooms in dirty work areas). It also includes using water to reduce dust, and systems for disinfecting cooling water. For control equipment, your supplier should provide a ‘user manual’. If you don’t have one, ask for it. And if this is impossible, you may need professional help to write one. The user manual should set out schedules for checks, maintenance and parts replacement.

For example, it should include:

  • A description of the system.
  • The daily checks the worker or supervisor needs to carry out, e.g. the ventilation is turned on, the airflow indicator gives the right reading.
  • The weekly or monthly checks the supervisor or owner needs to carry out, e.g. of equipment wear and tear, and that short cuts are not creating dangers.
  • Details of any thorough examination and test.
  • Signs of wear and control failure.
  • A list of replaceable parts.
  • A description of how operators should use the system so it works effectively.

Remedy defects in good time. It is pointless making checks if you take no action when something is wrong.

Checking And Maintaining

Once you’ve got control, you need to keep it. Regular checks and maintenance should be carried out as recommended to ensure the control measures remain and the equipment keeps working properly.

Please click the link to complete the test quiz – Test Quiz