The construction industry forms 5 to 15% of the national economy of most countries and is usually one of the three industries having the highest rate of work-related injury risks. The following chronic occupational health risks are pervasive (Commission of the European Communities 1993):
- Musculoskeletal disorders, occupational hearing loss, dermatitis and lung disorders are the most common occupational diseases.
- An increased risk of respiratory tract carcinomas and mesothelioma caused by asbestos exposure has been observed in all countries where occupational mortality and morbidity statistics are available.
- Disorders resulting from improper nutrition, smoking or use of alcohol and drugs are associated especially with migrant workers, a substantial portion of construction employment in many countries.
Preventive health services for construction workers should be planned with these risks as priorities.
Types of Occupational Health Services
Occupational health services for construction workers consist of three main models:
- specialized services for construction workers
- occupational health care for construction workers rendered by providers of broad-based occupational health services
- health services provided voluntarily by the employer.
Specialized services are the most effective but also the most expensive in terms of direct costs. Experiences from Sweden indicate that the lowest injury rates on construction sites worldwide and a very low risk for occupational diseases among construction workers are associated with extensive preventive work through specialized service systems. In the Swedish model, called Bygghälsan, technical and medical prevention have been combined. Bygghälsan operates through regional centres and mobile units. During the severe economic recession of the late 1980s, however, Bygghälsan severely cut back its health service activities.
In countries that have occupational health legislation, construction companies usually buy the needed health services from companies serving general industries. In such cases, the training of occupational health personnel is important. Without special knowledge of the circumstances surrounding construction, medical personnel cannot provide effective preventive occupational health programmes for construction companies.
Some large multinational companies have well-developed occupational safety and health programmes that are part of the culture of the enterprise. The cost-benefit calculations have proved these activities economically profitable. Nowadays, occupational safety programmes are included in quality management of most international companies.
Mobile health clinics
Because construction sites are often situated far from any established providers of health services, mobile health service units may be necessary. Practically all countries that have specialized occupational health services for construction workers use mobile units for delivering the services. The mobile unit’s advantage is the saving of work time by bringing the services to worksites. Mobile health centres are contained in a specially equipped bus or trailer and are especially suitable for all types of screening procedures, such as periodic health examinations. Mobile services should be careful to arrange in advance for collaboration with local providers of health services in order to secure follow-up evaluation and treatment for workers whose test results suggest a health problem.
Standard equipment for a mobile unit includes a basic laboratory with a spirometer and an audiometer, an interview room and x-ray equipment, when needed. It is best to design module units as multipurpose spaces so they can be used for different types of projects. The Finnish experience indicates that mobile units are also suitable for epidemiological studies, which can be incorporated into occupational health programmes, if properly planned in advance.
Contents of preventive occupational health services
Identification of risk at construction sites should guide medical activity, although this is secondary to prevention through proper design, engineering and work organization. Risk identification requires a multidisciplinary approach; this requires close collaboration between the occupational health personnel and the enterprise. A systematic workplace survey of risks using standardized checklists is one option.
Preplacement and periodic health examinations are usually conducted according to requirements set by legislation or guidance provided by authorities. The examination’s content depends on the exposure history of each worker. Short work contracts and frequent turnover of the construction workforce can result in “missed” or “inappropriate” health examinations, a failure to follow up on findings or unwarranted duplication of health examinations. Therefore, regular standard periodic examinations are recommended for all workers. A standard health examination should contain: an exposure history; symptom and illness histories with special emphasis on musculoskeletal and allergic diseases; a basic physical examination; and audiometry, vision, spirometry and blood pressure tests. The examinations should also provide health education and information on how to avoid occupational risks known to be common.
Surveillance and Prevention of Key Construction-related Problems
Musculoskeletal disorders and their prevention
Musculoskeletal disorders have multiple origins. Lifestyle, hereditary susceptibility and ageing, combined with improper physical strain and minor injuries, are commonly accepted risk factors for musculoskeletal disorders. The types of musculoskeletal problems have different exposure patterns in different construction professions.
There is no reliable test to predict an individual’s risk for acquiring a musculoskeletal disorder. Medical prevention of musculoskeletal disorders is based on guidance in ergonomic matters and lifestyles. Preplacement and periodic examinations can be used for this purpose. Non-specific strength testing and routine x rays of the skeletal system have no specific value for prevention. Instead, early detection of symptoms and a detailed work history of musculoskeletal symptoms can be used as a basis for medical counselling. A programme that performs periodic symptom surveys to identify work factors that can be changed has been shown to be effective.
Often, workers who have been exposed to heavy physical loads or strain think the work keeps them fit. Several studies have proved that this is not the case. Therefore, it is important that, in the context of health examinations, the examinees be informed about proper ways to maintain their physical fitness. Smoking has also been associated with lumbar disk degeneration and low-back pain. Therefore, anti-smoking information and therapy should be included in the periodic health examinations, too (Workplace Hazard and Tobacco Education Project 1993).
Occupational noise-induced hearing loss
The prevalence of noise-induced hearing loss varies among construction occupations, depending on levels and duration of exposure. In 1974, less than 20% of Swedish construction workers at age 41 had normal hearing in both ears. Implementation of a comprehensive hearing conservation programme increased the proportion in that age group having normal hearing to almost 40% by the late 1980s. Statistics from British Columbia, Canada, show that construction workers generally suffer significant loss of hearing after working more than 15 years in the trades (Schneider et al. 1995). Some factors are thought to increase susceptibility to occupational hearing loss (e.g., diabetic neuropathy, hypercholesterolemia and exposure to certain ototoxic solvents). Whole-body vibration and smoking may have an additive effect.
A large-scale programme for hearing conservation is advisable for the construction industry. This type of programme requires not only collaboration at the worksite level, but also supportive legislation. Hearing conservation programmes should be specific in work contracts.
Occupational hearing loss is reversible in the first 3 or 4 years after initial exposure. Early detection of hearing loss will provide opportunities for prevention. Regular testing is recommended to detect the earliest possible changes and to motivate workers to protect themselves. At the time of testing, the exposed workers should be educated in the principles of personal protection, as well as the maintenance and proper use of protection devices.
Occupational dermatitis is prevented mainly by hygienic measures. The proper handling of wet cement and skin protection are effective in promoting hygiene. During health examinations, it is important to stress the importance of avoiding skin contact with wet cement.
Occupational lung diseases
Asbestosis, silicosis, occupational asthma and occupational bronchitis can be found among construction workers, depending on their past work exposures (Finnish Institute of Occupational Health 1987).
There is no medical method to prevent the development of carcinomas after someone has been sufficiently exposed to asbestos. Regular chest x rays, every third year, are the most common recommendation for medical surveillance; there is some evidence that x-ray screening improves the outcome in lung cancer (Strauss, Gleanson and Sugarbaker 1995). Spirometry and anti-smoking information are usually included in the periodic health examination. Diagnostic tests for the early diagnosis of asbestos-related malignant tumours are not available.
Malignant tumours and other lung diseases related to asbestos exposure are widely underdiagnosed. Therefore, many construction workers eligible for compensation remain without benefits. In the late 1980s and early 1990s, Finland conducted a nationwide screening of workers exposed to asbestos. The screening revealed that only one-third of the workers with asbestos-related diseases and who had access to occupational health services had been diagnosed earlier (Finnish Institute of Occupational Health 1994).
Special needs of migrant workers
Depending on the construction site, the social context, sanitary conditions and climate may present important risks to construction workers. Migrant workers often suffer from psychosocial problems. They have a higher risk of work-related injuries than native workers. Their risk of carrying infectious diseases, such as HIV/AIDS, tuberculosis, and parasitic diseases must be taken into account. Malaria and other tropical diseases are problems for workers in areas where they are endemic.
In many large construction projects, a foreign workforce is used. A preplacement medical examination should be conducted in the home country. Also, the spreading of contagious diseases must be prevented through proper vaccination programmes. In the host countries, proper vocational training, health and safety education, and housing should be organized. Migrant workers should be provided the same access to health care and social security as native workers (El Batawi 1992).
In addition to preventing construction-related ailments, the health practitioner should work to promote positive changes in lifestyle, which can improve a worker’s health overall. Avoiding alcohol and smoking are the most important and fruitful themes for health promotion for construction workers. It has been estimated that a smoker costs the employer 20 to 30% more than a non-smoking worker. Investments in anti-smoking campaigns pay not only in the short term, with lower accident risks and shorter sick leaves, but also in the long term, with lower risks of cardiovascular pulmonary diseases and cancer. In addition, tobacco smoke has harmful multiplier effects with most dusts, especially with asbestos.
It is difficult to prove any direct economic benefit of occupational health services to an individual construction company, especially if the company is small. Indirect cost-benefit calculations show, however, that accident prevention and health promotion are economically beneficial. Cost-benefit calculations of investments in preventive programmes are available for companies to use internally. (For a model used extensively in Scandinavia, see Oxenburg 1991.)