Some jobs in the construction industry involve activities that can place workers at risk, unless the person has full, unimpaired control of their physical and mental capabilities. These jobs are called ‘safety critical' and the people who do them are ‘safety-critical workers'. You will need to decide whether an activity contains a safety-critical element and an incapacitated worker might expose themselves or others to a significant risk of harm. We will focus on health conditions that may involve, sudden loss of consciousness, impaired awareness or concentration, sudden incapacity, impaired balance or coordination, restricted mobility and impaired vision or hearing.

Before someone starts safety-critical work, it is good practice to check the person is fit.

A good example is crane operation. You need to be sure that a crane operator is able to climb the mast, can see well enough (this might mean making sure they use prescription lenses) and does not suffer from a condition which might cause them to lose consciousness or reduce their ability to concentrate.

Health surveillance is about systematic, regular checks on workers to identify early signs of ill health, and then acting on the results.Health surveillance is needed to protect workers who are at an increased risk, identify work-related ill health at an early stage so that steps can be taken to treat the condition and prevent further damage; and give early warning that protective control measures are no longer effective.

Health surveillance does not reduce the need to eliminate or manage health risks.

Formal health surveillance is only necessary if work damages health in a particular way and the following three factors all apply, there is a valid way to detect a disease or condition and it is reasonably likely that damage to health will occur under the particular conditions at work and health surveillance is likely to benefit the employee.

A good example is noise. Very loud noise is known to damage hearing. Hearing tests can detect the effect of noise on the hearing of people who work in noisy conditions. Hearing tests will benefit employees by identifying those at risk so that you can take measures to protect them and improve working conditions.

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