The main legislation concerning hazardous substances at work is the(COSHH) (or Control of Substances Hazardous to Health Regulations (Northern Ireland) 2003 (as amended)). It defines hazardous substances to include most hazardous chemicals (including waste and by-products), biological agents and any dust.
Harmful substances which are covered by COSHH include the vast majority of commercial chemicals. Examples may include:
Some hazardous substances are covered by separate specific regulations and are not covered by COSHH, asbestos and lead, for example. Substances which are dangerous just because they are explosive, flammable or radioactive are also not covered- they are covered by Dangerous Substances and Explosive Atmosphere Regulations 2002 (or Dangerous Substances and Explosive Atmospheres Regulations (Northern Ireland) 2003).
There are three main ways a substance can enter the body:
COSHH covers virtually all workplaces, requiring employers to prevent wherever reasonably practicable, workers' exposure to hazardous substances, and to control it where prevention is not possible.
Before exposing employees to hazardous substances, an employer must conduct a COSHH risk assessment. All the hazardous substances used in the workplace including waste and by-products must be identified, and information on each obtained. The first place to get information is the safety data sheet which suppliers must give with each product supplied. Other sources of information include product labels and other information from the manufacturer/supplier, HSE and HSENI guidance and publications and technical journals. For more guidance on this matter, visit the.
For Northern Ireland see the guidance notes on the. Next the employer must consider how likely is it that someone's health will be affected. How much of the substance is used/produced? Who may be exposed? Everyone has to be considered, including, for example, visitors, the public, contractors, employees working at other locations or at another organisation and especially cleaning and maintenance staff whose work may lead to them being highly exposed or those who may be at greater risk, such as pregnant, young or disabled workers or those more susceptible because of sensitivities or other diseases. How often and for how long may they be exposed? Are employees or others exposed to more than one substance since this may cause worse health effects? Are they also exposed to substances at home which may affect the level or mix of exposure? Again, it may be necessary to seek further information as given in the previous paragraph.
Specialist help may be sought for conducting risk assessments when there is no one with sufficient competence. A competent person is someone with an understanding of COSHH and with all the necessary information, knowledge, training and experience to understand and make correct decisions about the hazards and risks, the work and actions needed.
If significant risks are identified in step one of the risk assessment, the employer must consider how to prevent or minimise exposure and whether current controls are working and meet current HSE or HSENI, , industry, etc., guidance and good practice. Air monitoring and/or health surveillance results will help to indicate whether the controls are working.
The risk assessment must be recorded, kept readily available, and explain the findings and the necessary steps to control exposure. How much is recorded depends on the risk.
The assessment must be regularly reviewed. The type of work or extent of risk will determine how frequently. Reviews must also take place whenever it is suspected that they are no longer valid or when there has been a significant change. Checks on control measures, air monitoring results, health surveillance checks, work related ill-health, or information on new health risks may all indicate that a review is necessary. A significant change includes using a different substance or getting it from a new source, or a change in the controls, work process, or methods.
When reviewing an assessment, employers must consider preventing exposure or improving control measures even further. Changes in technology (control methods or equipment) or in the cost of alternatives may mean that it is now possible to prevent or further reduce exposure.
The COSHH regulations require employers to prevent exposure to substances hazardous to health, if it is reasonably practical to do so. Employers might change the process or activity so that the hazardous substance is not needed or generated. If this is not possible, then employers should replace it with a safer alternative, after having first considered the new risks this might create, or use it in a safer form, e.g. pellets instead of powder, which would reduce exposure to dust.
Only when preventing exposure is not reasonably practical, may the employer consider controlling exposure, and it should do so giving preference to the methods at the top of the 'hierarchy of control' (see below), but may use a combination of them as necessary:
If prevention is not reasonably practical, an employer must adequately control exposure. They should consider and put in place measures appropriate to the activity and consistent with the risk assessment, including, in order of priority, one or more of the following:
Under COSHH, adequate control of exposure to a substance hazardous to health means applying the eight principles of good practice set out in "Schedule 2A to COSHH", not exceeding the workplace exposure limit (WEL) for the substance (if there is one), and if the substance causes cancer, inheritable genetic damage or asthma, reducing exposure to as low a level as is reasonably practicable.
The HSE and HSENI has established workplace exposure limits for a number of substances hazardous to health. These are intended to prevent excessive exposure to specified hazardous substances by containing exposure below a set limit.
A WEL is the maximum concentration of an airborne substance, averaged over a reference period, to which employees may be exposed by inhalation. WELs are listed in the COSHH document "EH40/2005 Workplace exposure limits".
Correctly applying the principles of good practice will mean exposures are controlled below the WEL. Advice on applying the principles can be found in the "COSHH Approved Code of Practice (ACOP)" currently in its 5th edition and available either direct from the HSE or from major bookstores [ISBN: 0717629813].
COSHH acknowledges the particular hazards of substances which cause cancer, inheritable genetic damage or asthma, by requiring that exposure to these is reduced to as low a level as is reasonably practicable. The HSE and HSENI websites contain guidance on suitable controls.
For carcinogens (substances which may cause cancer), or mutagens (substances which may cause heritable genetic damage), special requirements apply. These are in regulation 7(5) of COSHH and explained in Appendix 1 of the COSHH ACOP.
If there is no WEL or if exposure is by absorption through or contact with the skin, or by ingestion, employers must set a standard at which nearly all the population could be repeatedly exposed and not suffer ill-health. The standard must be set after the appropriate information has been considered, for example the safety data sheet, HSE or HSENI guidance, technical papers, occupational medicine and hygiene journals.
Employers must keep control measures in efficient working order, good repair and clean, and ensure that they are properly used or applied. A competent person must examine, test and maintain them at suitable intervals. Visual checks should be carried out weekly. Control methods such as working procedures must also be reviewed. How often will depend on the degree of risk and the reliability of the control method. Records of tests and examinations must be kept for at least five years.
Employers must make proper use of the control measures, store them appropriately, and report defects to the employer immediately. Employers are responsible for providing employees with suitable training, information and supervision so that they are able to do this.
Employers must measure the amount of hazardous substances in the air breathed in by workers where there could be a serious health risk if control measures failed, where such measuring is necessary to ensure that exposure limits are not exceeded, or where control measures might not be working properly. The only exception is where there is some other system for checking exposure, such as an automatic alarm.
The monitoring process must be carried out in accordance with a suitable procedure and at an appropriate frequency, which will depend on the substance, the control measures used, and how close the exposure levels already are to the limits.
Records of the exposure monitoring must be kept for five years, except where they specifically relate to individuals, which must be kept for 40 years. They must be in a form that allows comparisons with any health surveillance records.
Employers must pay for and carry out health surveillance of workers exposed to hazardous substances where there is a reasonable likelihood of an identifiable disease or adverse health effect occurring under the working conditions, and detection is both possible and a low risk procedure to the employee. Whether the disease is likely to occur is a judgement based upon the frequency, duration, and type of exposure; toxicological data; and comparisons with other like substances, situations, and studies.
The purpose of health surveillance is to protect workers' health by detecting adverse health effects as soon as possible, to collect data to assist in detecting and evaluating health hazards, to check that the current control measures are sufficient and working properly, and to assess the immunity of employees working with biological agents (they may need vaccinations). Overall, the purpose is to benefit the workers, and it must not be used to discriminate against the less fit or more susceptible.
Where there is a period of time between exposure and when the possible ill-effect might occur, health surveillance may need to continue once exposure has ceased, but only so long as detection is possible at a sufficiently early stage.
Suitable facilities should be provided by the employer. The examination must be by a trained doctor or nurse, or possibly a trained supervisor, (for example if checking the skin of employees for dermatitis, or asking questions about breathing difficulties relating to asthma). The health surveillance procedures must be suitable and appropriate to the hazard and risk and be as non-invasive as possible. It may include the taking of samples, measurements and clinical examinations. Workers must turn up for health surveillance.
Records must be kept for at least 40 years from the last entry and in a form allowing comparisons with any exposure monitoring records.
If there is a risk of an accident, incident or emergency leading to exposure beyond the normal day-to-day risks, a plan must be drawn up. The purpose is to enable an immediate response by following set procedures and systems, such as emergency procedures, and procedures explaining how to warn and notify workers and the emergency services, etc. These "safety drills" need to be regularly practised and appropriate first-aid facilities must be provided. The plan needs to be reviewed, updated, and/or replaced as circumstances change.
If an uncontrolled escape of a hazardous substance takes place, immediate steps must be taken to minimise the harmful effects, return the situation back to normal, and inform employees who may be affected. All persons not concerned with the emergency should be excluded from the area, and others must be provided with the appropriate safety equipment including PPE.
This type of plan is not necessary where the quantities of the hazardous substance would present only a slight risk to health and the current control measures are sufficient and the substance is not a carcinogen, mutagen or biological agent.
Instruction, training and supervision
Employers must provide workers and others carrying out work in connection with their business (contractors and agency staff, for example), information on:
They must also provide sufficient and appropriate supervision and instruction to ensure that people at work do not endanger themselves or others by not knowing what they should do, what precautions to take and when to do so. They must ensure that workers understand the risks.