2.Health surveillance of workers must be carried out in accordance with the principles and practices of occupational medicine; it must include at least the following measures:
keeping records of a worker's medical and occupational history,
a personal interview,
where appropriate, biological surveillance, as well as detection of early and reversible effects.
Further tests may be decided upon for each worker when he is the subject of health surveillance, in the light of the most recent knowledge available to occupational medicine.