What is Health Surveillance

Health Surveillance is a process involving a range of strategies and methods to systematically detect and assess the early signs of adverse effects

on the health of workers exposed to certain health hazards and subsequently acting on the results.

In simple terms, Health Surveillance means watching out for early signs of work-related ill health in employees exposed to certain health risks.

Methods can be simple or more complex depending on the risks to employees from the hazards of the job.

Why carry out Health Surveillance?

Some forms of Health Surveillance are required by law. Other forms of Health Surveillance are undertaken as good practice (e.g. pre-employment assessments as to fitness to work in the particular job).

Health Surveillance can:

•         help protect the health of employees

•         help you make sure employers are complying with the legal requirements for a safe workplace

•         allow detection of any adverse health effects at an early stage

•         assist in the evaluation of control measures

•         provide information useful in the detection of hazards and assessment of risks.

Health Surveillance should be conducted when:

•         there is an identifiable disease or other identifiable adverse health outcome

•         the disease or health effect may be related to exposure

•         there is a likelihood that the disease or health effect may occur

•         there are valid techniques for detecting indications of the disease or health effects.

Simple methods of Health Surveillance

Non-technical Health Surveillance techniques include:

Simple skin surveillance

Looking for skin damage on hands from using certain chemicals.

Simple respiratory surveillance

Asking employees to fill in a respiratory questionnaire to assess whether they have developed any breathing problems from substances they work with.

Technical methods of Health Surveillance:

Lung health

Spirometry tests: A lung function test to assess the capability of the lungs in gaseous exchange. This will detect any underlying damage to the lungs.

The participant has to blow into a tube and totally empty the lungs. The test takes approximately three minutes and three tests are carried out to give the best results.

The appointment would be approximately 30 minutes to cover administration and assessment by the nurse.

Occupational asthma or other respiratory diseases can be picked up by this procedure although further intervention will be required.


Audiometry tests: A hearing test to assess any hearing defects which may have been caused by exposure to noise at work.

This requires the participant to sit in a sound proof booth. Earphones and a handset are provided and the individual uses the handset when noises are heard.

The noise is heard through the earphones and will vary in frequency and levels of loudness. Both the right and the left ear are tested and a printout is given at the end which can be read by the practitioner.

Noise-induced hearing loss can be picked up by the results although further intervention will be required.

Other examinations, tests and assessments

In addition to the above there may be a requirement for medical examinations, urine tests or blood tests depending on the work activities and the employee’s exposure to various substances or hazards.

It may be necessary to carry out a noise assessment or air sampling to determine whether these tests are required.

Such tests are normally carried out by an Occupational Hygienist although the sampling can be performed by competent persons in the workplace if they have had appropriate training and the proper equipment.

The type of business and the level of risk will determine whether it is worth paying the cost of training and equipment to conduct the tests in-house, rather than a periodic assessment by an Occupational Hygienist.

When is Health Surveillance necessary?

The starting point of any Health Surveillance is the Risk Assessment.

Once this has been completed, all hazards and health hazards in the workplace should be identified.

The following steps are important prior to any Health Surveillance being carried out:

1.      find out what the hazards are

2.      identify who might be at risk from exposure to those hazards and how

3.      decide what to do to prevent harm to health, e.g.:

•         remove the hazard altogether

•         reduce risks by changing the way work is done or use other controls

•         provide protective equipment.

If the above steps have been completed, and risks still remain, you will need to take further steps to protect employees.

Employers must find out whether their employees are at risk from:

•         noise

•         vibration

•         respiratory disease

•         skin disease or irritation

•         eye irritation

•         kidney or liver damage.

In order to answer these questions, the person conducting the risk assessment must understand the full work process and all of the risks employees are exposed to.

The main areas of concern are:

•         solvents

•         fumes

•         dusts

•         biological agents

•         asbestos

•         lead

•         compressed air

•         ionising radiations

•         diving.

Some forms of Health Surveillance are required by law. Other forms of Health Surveillance are undertaken as good practice (e.g. pre-employment assessments as to fitness to work in the particular job).

When is Health Surveillance carried out and who can do it?

In its simplest form, Health Surveillance involves employees checking themselves for signs or symptoms of ill health. However, self-checks can only be carried out where they are part of a wider Health Surveillance programme.

Self-checks only work where employees have been properly trained on what to look for and know to whom to report symptoms. An example would be employees noticing soreness, redness and itching on their hands and arms, where they work with substances that can irritate or damage the skin.

A responsible person can be trained to make basic checks such as skin inspections for first signs of redness. The responsible person could be a supervisor, employee representative or a first aider.

For more complicated assessments, such as medical fitness for specific jobs, lung function tests, hearing tests, etc. an Occupational Health Nurse can perform the assessment and do various examinations.

Some jobs may only require the employee to fill in a questionnaire, which can be screened by the Occupational Health Nurse. This is normally done for new employees to ensure fitness for the type of post but can also be done periodically for jobs with specific hazards.

For more complicated procedures, an Occupational Health Physician may be required.

Common examples of Health Surveillance

•         Display Screen Equipment Use: Vision Screening; Muscular Assessment; Work Station Assessment

•         Drivers: Occupational Health Assessment

•         Manual Handling work: Occupational Health Assessment or questionnaire

•         Noise: Hearing test if exposure at levels of 80Db or above

•         Vibration: Self reporting examination or questionnaire + Occupational Health examination if required

•         Asbestos, lead, compressed air: Occupational Health Assessment

•         Substances Hazardous to Health: Varies depending on substance. Self reporting; Occupational Health Assessment; Respiratory function tests; Skin surveillance; Blood test; Urine tests

•         Ionising Radiations: Dosimetry; Personal monitoring

•         Laser users: Eye examination

•         Confined spaces – use of respirators: Occupational Health medical

•         Pregnant workers: Occupational Health Assessment or questionnaire

•         Night work: Occupational Health Assessment or questionnaire

Health Surveillance Records

Where any health information is written down, such as lung function test reports, records have to be kept for a minimum of 40 years. These are normally kept by the Occupational Health provider.

Glossary of Health Surveillance terms

Biological Monitoring: testing for the presence of a hazardous substance, its metabolites or a biochemical change in a person’s body tissue, exhaled air or fluid.

Carcinogenic: capable of causing cancer.

Chemical name: the scientific or technical name of a substance.

Code of Practice: a systematic collection of rules, standards and other information relating to the practices and procedures followed in an area.

Control Measures: ways of preventing or minimising a person’s exposure to a hazardous substance. A hierarchy of controls ranks measures taken to prevent or reduce hazard exposure according to effectiveness.

Corrosive: capable of destroying materials or living tissue (e.g. skin) on contact.

Cytotoxic: having the property of being destructive to living cells

Exposed: a person is exposed to a hazardous substance if the person absorbs, or is likely to absorb, the substance by ingestion or inhalation or through the skin or mucous membrane.

Harmful: capable of causing health problems after larger or long-term exposures.

Hazard: the hazard presented by a substance is its potential to cause harm. It may be able to cause illness or damage or even lead to death.

Hazardous Substance: a chemical or other substance that can affect workers' health, causing illness or disease; and any substance for which the supplier, manufacturer or importer must provide a current material safety data sheet. Since September 1997, hazardous substances include those with carcinogenic, mutagenic and teratogenic effects, and cytotoxic drugs.

Health Surveillance: the monitoring (including biological monitoring or medical examination) of a person in relation to the person’s exposure to a hazardous substance. Surveillance is for the purpose of identifying changes in health status due to exposure.

Hierarchy of Controls: ranking of measures taken to prevent or reduce hazard exposure according to effectiveness. That is from the most effective measures that eliminate hazards to the least satisfactory that achieve only limited protection.

Mutagenic: having the property of causing genetic mutations.

Teratogenic: having the property of causing malformation of an unborn child.