Health and Safety Law:  Hazardous Substances

Individuals who are exposed to hazardous substances during the course of their working lives are put at great risks against their health. Accordingly appropriate legislation needs to be put in place to ensure appropriate health and safety requirements are put in place by all employers who deal with hazardous substances to protect their employees.

Control of Substances Hazardous to Health Regulations 2005

The Control of Substances Hazardous to Health Regulations or COSHH came into force in April 2005 and impose a duty on all employers who deal with hazardous substances to ensure the health and safety of their employee’s.

Hazardous Substances

What is meant by Hazardous Substances?

The Regulations define a hazard in relation to a substance as meaning the intrinsic property of that substance has the potential to cause harm to the health of a person

Substances which are said to be hazardous to health therefore include the following substances:

  • Substances which are classified as dangerous to health under the chemicals regulations. These substances must all have a warning label and each supplier must provide data sheets for them which will help in their identification.

  • Certain biological agents such as bacteria and other micro-organisms if they are directly connected with work. Examples of this kind of work will be in the farming industry, the treatment of sewage and even healthcare where the exposure is incidental to the work.

  • Pesticides

  • Medicines

  • Cosmetics

  • Any substances produced in chemical processes

  • Any other substance which creates a risk to health

Excluded Substances

The following substances are not covered by the Control of Substances Hazardous to Health Regulations:

  • Asbestos – regulated by the Control of Asbestos at Work Regulations 2002
  • Substances which are hazardous only because they become radioactive at high pressure, at extreme temperatures or have explosive or flammable properties – regulated by the Control of Major Accidents Hazards (Amendment) Regulations 2005

Duty of Employers under the Regulations

The Control of Substances Hazardous to Health Regulations specifies various duties which all employers when concerned with hazardous substances should adhere to. They are as follows:

  • Assess the risks through a risk assessment

  • Decide what measures need to be put in place and then implement them

  • Control the exposure

  • Monitor the Exposure

  • Maintain the measures in place

  • Review the measures in place

  • Prove appropriate training to employees

Risk Assessment

All employers who deal with hazardous substances during the course of their business must undertake a full risk assessment taking into account the following factors:

Risk assessments undertake concerning the control of substances hazardous to health regulations will often be done in according with the Personal Protective Equipment at Work Regulations in order to make assessments on whether protective equipment will be needed for employees exposed to the hazardous substance.


In order to control the exposure to the hazardous substance the employer will be expected to undertake the following tasks:

  • Put in place arrangements for the safe handling, storage and transport of the substances and of waste containing such substances
    adopting suitable maintenance procedures;

  •  reducing to the minimum required for the work concerned the following:

    1. the number of employees subject to exposure

    2. the level and duration of exposure, and

  • the quantity of substances hazardous to health present at the workplace                   

  • controlling all aspects of the working environment in particular putting in place appropriate ventilation and ensuring workers have rest areas away from the exposure of the substance

  •  putting in place appropriate hygiene measures including adequate washing facilities

All the above measures will then have to be consistently monitored and reviewed in order to maintain the control and in some instances to remove them and replace them with more appropriate control measures.

Training and Information

All employees who are exposed to the hazardous substances must receive full training and information in relation to the following factors:

  • Details of the substances hazardous to health to which the employee is liable to be exposed including 

  • The names of those substances and the risk which they present to health

  • Any relevant occupational exposure standard, maximum exposure limit or similar occupational exposure limit

  • Access to any relevant safety data sheet        

  • The significant findings of the risk assessment            

  • The precautions which must be taken by the employee in order to safeguard himself and other employees in the workplace 

  • The results of any monitoring of exposure to the hazardous substance  

  • The results of any health surveillance undertaken

Joint Responsibility

The Control of  Substances Hazardous to health regulations are said to require joint responsibility as an employer must have a duty of care towards his workers and fellow employees whereas implied within the regulations each employee will have a duty of care towards his fellow workers.

When concerned with employment around hazardous substances health and safety must be paramount.