Medical Surveillance Icon Medical Surveillance

Medical surveillance describes activities that target health events or a change in the biologic function of an exposed person or persons. A surveillance programme involves recurrent longitudinal examinations and data analysis over time.

The principal objectives of a medical surveillance programme are:

  • To ensure that employees are fit for and suited to the work they are to do and that they meet the inherent requirements for their relevant occupations.
  • To establish reference points for the medical information on all employees, especially those exposed to health hazards; notably, baseline data on entry, job transfer, and exit data when they leave, against which work-related changes may be identified more readily.
  • To identify early adverse effects of exposure to hazards in their work or working environment, thereby determining the efficacy of hazard control measures.

These objectives of a medical surveillance programme are supported by The Employment Equity Act which expressly forbids medical testing unless the testing is permitted or required by legislation, e.g. the Occupational Health and Safety Act or is justifiable in the light of the inherent requirements of the job.

There are several pieces of legislation which require medical testing for employees to perform certain types of work. The foremost part of the legislation is the Occupational Health and Safety Act 85 of 1993 (OHSA), but it also includes the National Road Traffic Act and the Hazardous Substances Act.

The OHSA provides for the protection of the health and safety of employees and other persons at companies and institutions and requires risk assessment, exposure measurement and risk control. How this act refers to fitness to work is mainly within its regulations, such as the Construction Regulations, Driven Machinery Regulations, Hazardous Chemical Substances Regulations, the Hazardous Biological Agents Regulations, the Lead Regulations, and the Noise-Induced Hearing Loss Regulations.

This statutory fitness to work examinations is driven by:

  • The Tasks:
    • Drivers of hazardous self-propelled mobile equipment
    • Construction workers, confined space workers, workers at height, operators of lifting equipment, laboratory workers, food handlers, etc
    • Workers required to wear a respirator
    • Workers needed to work the night shift.
  • The Hazards:
    • Workers potentially exposed in terms of the OHSA: Hazardous Chemical substances, Hazardous biological Agents, asbestos, lead, noise, heat, cold.
    • Workers potentially exposed in terms of the Hazardous Substances Act: radiation

The inherent requirements of the job are the essential components (core activities, tasks or skills) of the role that, if not met, the job cannot be done. The inherent health requirements of a job are the minimum physiological thresholds of function, or the degrees of tolerance for dysfunction, necessary to meet the identified inherent needs of the job, safely and effectively.

"Inherent health requirements" or minimum medical standards of fitness refer to the capability of the employee to perform the tasks required:

  • to the required standard (quality & efficiency)
  • without undue risk to him/herself or others (safety)
  • The ability to function in the working conditions associated with the job (i.e. potential to be exposed to specific hazards), without undue risk to his or her health.

The inherent requirements of the job need to be detailed in the job description for the minimum standards of fitness (inherent health requirements) to be identified.

Health Surveillance

Dr Haidee Williams will help:

  • Design the specific medical surveillance programmes required by the findings of the site's SHE risk assessment, and continually review them.
  • Review outcomes of all occupational health tests, for adverse exposure effects, and impacts on medical fitness to work and manage the deviation.
  • Analyse data from surveillance programmes using sound epidemiological methods to identify trends in employee health.


Dr Haidee Williams offers specialist occupational medicine services with an interest in developing evidenced based safety, health and environment policies and programmes. Expertise includes medical examinations, medical adjudication, toxicology, health based risk assessments, hazardous chemical substances, hazard communication and training and guidance on H,S&E legal compliance requirements.


Practice: 2 Wycombe Avenue, Constantia, Cape Town, 7806
Tel: 087 809 0054
Mobile: 083 271 4551
Twitter: @drhmwilliams