13.1.1. Medical surveillance includes, where appropriate, pre-assignment and periodical medical examinations. It also includes, where appropriate, medical examinations upon resumption of work after a prolonged absence for health reasons, and upon and after termination of work involving exposure to chemicals.
13.1.2. Medical surveillance, conducted by an approved medical practitioner, should be used as part of overall health surveillance, in accordance with the objectives and principles of the Occupational Health Services Recommendation, 1985 (No. 171). Health surveillance should also include, where appropriate, simple techniques for the early detection of effects on health. These could include examination and questioning about health complaints.
13.1.3. Where necessary, the employer, or the institution competent under national law and practice, should arrange, through a method which accords with national law and practice, medical surveillance of workers:
(a) for the assessment of the health of workers in relation to risks caused by exposure to chemicals;
(b) for the early diagnosis of work-related diseases and injuries caused by exposure to hazardous chemicals;
(c) for the assessment of the workers' ability to wear or use required respiratory or other personal protective equipment.
13.1.4. In the case of exposure of workers to specific hazards, medical and health surveillance should include, where appropriate, any examination and investigations which may be necessary to detect exposure levels and early biological effects and responses.
13.1.5. When a valid and generally accepted method of biological monitoring of workers' health exists for the early detection of the effects on health of exposure to specific occupational risks, it may be used to identify workers who need a detailed medical examination, subject to the individual workers consent.
13.1.6. Medical surveillance is necessary where:
(a) it is required by national law whenever workers are liable to be exposed to chemicals hazardous to health; or
(b) the employer is advised by an occupational health service that it is necessary as part of the protection of workers exposed to chemicals hazardous to health, given special attention to pregnant and breastfeeding women and other susceptible workers; or
(c) atmospheric or biological monitoring show that there could be effects on the health of a worker because of exposure to chemicals at work and medical surveillance will assist early detection of ill effects.
13.1.7. Exposure to the following types of chemicals may be appropriate for medical surveillance:
(a) chemicals that have a recognised systemic toxicity, i.e. an insidious poisonous effect;
(b) chemicals known to cause chronic effects, e.g. occupational asthma;
(c) chemicals known to cause severe dermatitis;
(d) chemicals that are known or suspected carcinogens;
(e) chemicals that are known or suspected teratogens or mutagens, as science develops;
(f) other chemicals where there is a likelihood that the disease or effect may occur under particular conditions of the work activity.
13.2.1. Where the results of medical tests or investigations reveal clinical or preclinical adverse effects, appropriate medical treatment should be provided and measures should be taken to improve the working conditions and environment with a view to preventing or reducing exposure of the workers concerned. In order to prevent further deterioration of their healths these measures should include a reassessment of the risks and corresponding control measures of relevant hazardous chemicals, and appropriate clinical re-evaluation of the health status of the workers should be carried out periodically.
13.2.2. The results of medical examinations should be used to determine health status with respect to exposure to chemicals, and should not be used to discriminate against the worker.
13.2.3. The results of medical examinations and biological monitoring should be clearly explained to the workers concerned.
13.3.1. The conditions under which, and the time during which, records resulting from medical surveillance of workers should be kept, the conditions under which they may be communicated or transferred and the measures necessary to keep them confidential, in particular when the information they contain is placed on computer, should be in accordance with national laws or practice, governed by recognised ethical guidelines. Where there are no recognised national laws or practice, a period of 30 years is recommended for keeping medical surveillance records.
13.3.2. Workers should have access to their own medical records. either personally or through their own physicians.
13.3.3. Workers and their representatives should have access to the results of studies prepared from medical records, where individual workers cannot be identified.
13.3.4. The results of medical records should be made available to prepare appropriate health statistics and epidemiological studies, provided anonymity is maintained, where this may aid in the recognition and control of occupational diseases.
13.3.5. The competent authority should make arrangements in accordance with national practice to ensure that medical records are maintained for establishments that have closed down.