Managing Hazardous Substances under COSHH

Suppliers MSDSs are a good place to start for substance that are used in manufacture or cleaning. Other sources of advice about hazardous substances that may be present include the HSE, trade associations and trade unions.

The assessment should identify the hazards, the groups of
workers who may be exposed and the prevention and control
measures to be used. Remember to include foreseeable abnormal situations that may cause greater exposure – e.g. a spillage, a burst pipe or occasions where normally enclosed machinery has to be broken down for cleaning.

In April 2005 the regulations were modified. A new duty to
comply with eight basic principles of good practice for any
hazardous substance was introduced. These are:
• Design and operate processes to minimize emission or spread of hazardous substances
• Take account of all relevant routes of exposure
• Use control measures that are proportionate to the health risks
• Where possible use the most effective control measures that minimize the escape and spread of hazardous substances
• If adequate control cannot be achieved by other means use suitable personal protective equipment along with the other controls
• Check and review regularly to make sure that controls are working
• Inform and train all employees on the hazards and risks and the use of controls
• Make sure that the introduction of controls does not increase the overall risk to health and safety.

This means there is a hierarchy of control measures that should be considered.

Eliminating the Hazard Is there a safer substance that can be used? Can the process be changed to prevent the production of hazardous fumes or dust? Can a safer form of the substance be used – e.g. if a powder produces a dust hazard, is there a pelletised form which is less dusty or can a pre-mixed solution be used to avoid the need for mixing?

Enclosure Isolating the source from the majority of workers can help. However some people may be exposed if there is a rupture in containment or if maintenance work has to be done inside the enclosed area.

Ventilation General ventilation that provides sufficient fresh air may be suitable for low-grade hazards. For some substances local exhaust ventilation (LEV) may be needed at the point where the dust or fume is produced. LEV should be designed to remove dust or fumes before they get into workplace air. The shape, size and location of the intake and the design of ducting and pipework can greatly affect the efficiency of the extraction. Dust or fumes drawn into the extraction system must be disposed of safely.

Material Handling Dust or fumes are often produced when workers have to handle substances – e.g. to load products into a mixing vessel. Automation or mechanical aids can reduce the need to pour from sacks, drums or kegs. This can reduce the risk of dust, fumes or splashing and may also reduce manual handling risks.

Organisational Controls Restricting access to areas where hazardous materials are present reduces the number of workers exposed to risk. Good housekeeping to clean up spills and make sure that hazardous substances are properly stored can help.

Washing and changing facilities may be needed for some workers. Workers exposed to the risk must be informed and should be trained so that they can follow the control procedures.

Personal Protective Equipment As a last resort or as a temporary measure – e.g. in emergency situations – workers may have to use PPE. PPE should be suitable for the job in hand and should comply with the relevant European standards.

For tight-fitting respirators (e.g. disposable masks, half masks and full face masks) the initial selection should include a fit-test to make sure that it is suitable for the wearer. The test must be done by a competent person using the appropriate test equipment and the test results should be recorded. Advice should be available from the supplier. Workers who are required to wear PPE should be trained in its use.