Hazardous substances

Exposure to substances hazardous to health is a daily occurrence for thousands of workers in the offshore oil and gas industry. Many of these substances have the potential to cause health effects eg skin disease such as dermatitis, cancer and lung disease such as asthma. The Control of Substances Hazardous to Health (COSHH) Regulations 2002 (as amended) place responsibility on the employer for taking effective measures to control exposure and protect health.

COSHH in the offshore oil and gas industry

Application of COSHH Offshore

The COSHH Regulations apply to all locations and activities in the offshore industry where the Health and Safety at Work etc Act 1974 applies. This covers offshore installations and pipeline works (including pipe-lay barges) on the UK sector of the Continental Shelf (UKCS); as well as vessels working in connection with offshore installations to carry out activities such as construction, maintenance, diving operations etc.

General COSHH Requirements

COSHH aims to protect workers and others from adverse effects of exposure to substances hazardous to health. It does this by requiring assessment of risk, control of exposure, monitoring and maintenance of controls, health surveillance and the provision of information, instruction and training.

Duties and responsibilities

The main duties under COSHH fall on employers. This means that owners, operators and contractors all have responsibilities which cover both their own employees and others who may be affected by their activities.

Management of COSHH


Effective control of health risks depends on co-operation and co-ordination of activities. This is particularly important offshore where a number of employers and their employees may be involved in an operation. Although, management arrangements offshore are often complex, the simple, guiding principle is that whoever is in control of an operation must ensure that adequate arrangements are in place. Management arrangements might include appointment of COSHH co-ordinators. Employers will need to ensure that the appointed people are competent to carry out their functions. Anyone with duties under COSHH may make arrangements with others to carry out those duties. Legal responsibility, however, remains with the employer (the operator, owner or contractor as appropriate) – the employer must ensure the duties are carried out properly.

Risk assessments

COSHH risk assessments are a key part of ensuring worker safety by helping you to assess the risks to your workers from hazardous chemicals. Assessments should consider:

  • Substances used: information on the hazardous properties of a substance and its risk potential is essential.  You can find out by checking Safety data Sheets, asking the supplier, looking at industry guidance or checking on the internet eg HSE's website
  • Work and working practices: if the substance is harmful, how might workers be exposed eg breathing in gases/fumes/dusts, contact with the skin/eyes, swallowing. Bear these in mind when you look at the tasks.

Risk assessment is not just a paper exercise. It's about taking sensible steps to prevent ill health. You need to know how workers are exposed and to how much, before you can decide if you need to do anything to reduce exposure.

Although there is no obligation under COSHH to record an assessment, it makes sense to write down what steps you have taken to identify the risks. And the really important part is to making a list of the actions you are taking to control the risks to health. These need to be available to those carrying out the work so that they can be readily used.

Prevention and control of exposure

COSHH requires exposure to be prevented or, where this is not reasonably practicable, adequately controlled. Control measures are always a mixture of equipment and ways of working to reduce exposure. The right combination is crucial and no measures, however, practical, can work unless they are used properly.

The ACOP gives a hierarchy of preferred control measures and sets out how adequate control may be achieved. The use of personal protective equipment (PPE), including respiratory protective equipment (RPE) is only acceptable as a last resort in addition to other means if these alone cannot provide adequate control. Schedule 2A of COSHH sets out 8 principles of good control practice, which can be used as a checklist for assessing your approach to control. In addition, HSE has developed a free internet tool for identifying good control practice. It covers a wide range of processes and activities and includes the guidance on good control practice for the offshore oil and gas industry ie Offshore COSHH Essentials.

Offshore COSHH Essentials

Offshore COSHH Essentials was prepared in partnership by an HSE/Industry/Unions working group and describes good control practice for controlling exposure to chemicals, for a range of common processes and tasks in the offshore industry. The guidance is aimed at managers, safety practitioners, offshore medics and safety representatives in the offshore oil and gas industry, who have responsibility for managing the control of substances hazardous to health.

The guidance consists of a series of Offshore COSHH Essentials (OCE) sheets giving practical advice on good control practice for specific tasks and a series of Offshore COSHH Method (OCM) sheets, which give advice on generic COSHH issues such as PPE, health surveillance etc. These OCE and OCM series are part of a suite of guidance on offshore health risks and includes Offshore Food Essentials (OFE) and Offshore Radiation Essentials (ORE).

Offshore essentials guidance (OCEs, OCMs, OFE and ORE)

The OCE sheets are not your COSHH assessments, but they will help you to assess the risks for named tasks and identify good control practice as well as reviewing existing control practice. An individual duty holder is unlikely to need all the sheets and should therefore select and download the appropriate sheets for the process or task that they are interested in and follow the advice given. It is important to look at all the advice and not pick and choose bits of advice, as all the points work together to provide adequate control. Implementing all the advice means that you will be following good control practice and will normally comply with exposure limits. You can also compare any controls you already use with the advice from Offshore COSHH Essentials. If the controls you have in place are the same or more stringent than those recommended by the guidance, then you are likely to be taking the right type of action.

Health surveillance

Employers have a duty to provide health surveillance for their employees only: an installation operator would not be under a duty to provide health surveillance for a contractor's employees. Contractors who do not have good access to specialist advice and services could ask the client company to agree to provide the necessary facilities, providing copy records for the contractor: or they could use an independent, recognised occupational health centre.

Information, instruction and training

Operators and owners need to ensure that the management on each installation is competent to apply COSHH requirements. When a number of employers are involved, information, instruction and training needs to be co-ordinated to ensure everyone is competent. Employers should also ensure that information provided for COSHH is made available to employees' safety representatives.

Safety representatives and the workforce

Involvement of employees in identifying and assessing COSHH hazards is very important. Individual employees have legal duties to take care of their own and others' health and safety and co-operate with management in meeting their obligations. They can only do this if they are involved. They also need to be involved because:

  • They are in direct contact with work hazards and may know what the problems are at first hand;
  • They are more likely to follow precautions if they have helped to identify them;
  • It will help to create a commitment to health and safety at all levels

With many different work groups present on an installation co-operation between employees is as important as co-operation between their employers. This can only be achieved if the workforce is involved.

Updated 2021-02-17