Adequacy of Precautions Against Exposure
The employer must determine the Adequacy of Precautions having regard only to the nature of the substance; and the nature and degree of exposure to Substances Hazardous to Health.
Exposure by Inhalation
As regards exposure by inhalation of certain substances, the Control of Substances Hazardous to Health (COSHH) Regulations include additional criteria for determining adequacy of control.
Maximum Exposure Limits (MEL) For Inhalation
Where there is exposure to a substance for which a maximum exposure limit is specified in COSHH, the control of exposure by inhalation is not adequate if the exposure level is at the maximum limit. The control is adequate only if the level of exposure is reduced as far as is reasonably practicable below the maximum exposure limit.
The employer should consult Schedule 1 of the Control of Substances Hazardous to Health (COSHH) Regulations (see Publications and Assistance on Managing Health Risks of Substances) if he is not sure whether any substances in his undertaking have been assigned a maximum exposure limit.
Occupational Exposure Standards (OES) For Inhalation
If exposure to a substance for which an occupational exposure standard has been approved, the control of exposure by inhalation may be adequate if that occupational exposure standard is not exceeded; or where that occupational exposure standard is exceeded, the employer identifies the reasons for the standard being exceeded and takes appropriate action to remedy the situation as soon as is reasonably practicable.
The employer should consult the most recent Health and Safety Commission List of Approved Occupational Exposure Standards if he is not sure whether any substances in his undertaking have been assigned an occupational exposure standard (see Publications and Assistance on Managing Health Risks of Substances).
Where No MEL or OES Applies
For substances hazardous to health where no maximum exposure limit or occupational exposure standard is assigned, exposure by inhalation should be controlled to a level to which nearly all the population could be exposed, day after day, without adverse health effects.
Exposure Other Than By Inhalation
As regards non-inhalation routes of exposure (such as swallowing, absorption through the skin or mucous membranes and contact with the skin or mucous membranes), exposure should be controlled to a standard such that nearly all the population could be exposed repeatedly without any adverse health effect.