COSHH Health Surveillance: When Is It Required?
- COSHH health surveillance is required where an identifiable disease or adverse effect is linked to exposure, valid detection is possible and workplace conditions make the effect reasonably likely.
- Health surveillance is repeated, risk-based checking and is not the same as general health screening, wellbeing checks or exposure monitoring.
- The employer keeps a restricted health record, while confidential clinical information remains in the medical record held by the occupational health professional.
- A concerning individual or collective result must trigger action on exposure and controls; surveillance never substitutes for preventing or adequately controlling exposure.
COSHH health surveillance is required when workers remain exposed to a substance associated with an identifiable disease or adverse health effect, there is a valid way to detect it, and workplace conditions make the effect reasonably likely. It is a repeated, risk-based programme and never a substitute for preventing or adequately controlling exposure.
The scheme should be selected with competent occupational health input and must protect medical confidentiality.
What is health surveillance?
HSE defines health surveillance as repeated health checks used to identify ill health caused by work. Its purposes include detecting adverse changes early, evaluating health hazards and checking whether controls are protecting workers.
Examples can include skin checks for dermatitis, respiratory questionnaires and lung-function testing for occupational asthma risks, or specific medical surveillance required for certain substances and processes.
The method must be linked to a known workplace hazard. A generic annual medical or wellbeing questionnaire is not automatically COSHH health surveillance.
When is COSHH health surveillance required?
HSE's COSHH health-surveillance guidance sets out three central conditions:
- There is a disease or adverse health effect associated with the substance or exposure.
- It is possible to detect the disease or adverse change and reduce the risk of further harm.
- Workplace conditions make it likely that the disease or effect could occur.
COSHH also contains specific provisions for certain listed substances or processes. Check the current regulation and HSE guidance rather than relying only on the three-question screen.
The assessment should consider residual exposure after controls, frequency and duration, routes of exposure, health effects, control reliability and relevant worker groups.
Which exposures commonly prompt surveillance consideration?
Common scenarios include work with respiratory sensitisers, substances causing occupational dermatitis, particular carcinogens or substances subject to specific medical-surveillance requirements.
Examples are not automatic rules. A product containing a sensitising ingredient may be used in a sealed system with no realistic exposure, while a lower-concentration mixture sprayed frequently may create a credible risk.
Consider non-routine work. Cleaning, maintenance, filter change, spill response and equipment breakdown can create exposure not visible during normal production.
Is health surveillance the same as exposure monitoring?
No. They measure different things.
| Activity | Main question |
|---|---|
| Exposure monitoring | What amount of a hazardous substance reaches the worker or workplace? |
| Health surveillance | Is there an early adverse health change linked to work? |
| General health screening | What is the person's broader health status, regardless of a specific workplace risk? |
| Biological monitoring | How much of a substance or metabolite has entered the body? |
Exposure monitoring can help evaluate controls, while health surveillance looks for effects or early indicators. A scheme may use more than one approach, but terminology and records should remain clear.
Who decides what surveillance is suitable?
The employer identifies the need through the COSHH assessment and arranges the scheme. A competent occupational health professional should advise on the method, frequency, referral criteria and interpretation.
Some low-complexity skin inspection schemes can involve a trained responsible person with occupational health oversight. Other surveillance requires a nurse, doctor or HSE-appointed doctor.
The provider must understand the exposure and work, not just administer a test. Give them the assessment, SDS, monitoring data, control information, worker groups and incident history.
What happens before surveillance starts?
Build the scheme in a controlled sequence:
- Confirm the hazardous exposure and health effect.
- Check whether control can be improved further first.
- Identify workers with actual or potential exposure.
- Select a valid method and baseline where appropriate.
- Consult workers and explain purpose, confidentiality and outcomes.
- Define frequency, triggers and referral routes.
- Establish health and medical record responsibilities.
- Decide how collective trends will be reviewed.
- Specify actions for abnormal, missed or inconclusive results.
Surveillance should be accessible during working time and should not penalise workers for reporting symptoms.
What records does the employer keep?
The employer keeps a health record, which can include the worker's identity, jobs or exposures, surveillance dates, the person carrying it out and the outcome such as fit, fit with restrictions, recall or referral.
The record should not contain confidential clinical notes or test detail without the worker's written consent. HSE's record-keeping guidance distinguishes the employer health record from the medical record.
The medical record contains confidential clinical information and is held by the occupational health professional. Managers generally receive only the fitness and control-relevant outcome needed to protect the worker.
HSE gives 40 years as the COSHH retention period for health records. Plan secure access, provider transfer and business-closure arrangements before records become inaccessible.
What should happen after an adverse result?
Protect the worker and investigate exposure. The occupational health professional may recommend review, referral or restrictions, while the employer reviews the risk assessment and controls.
Actions can include:
- Checking whether symptoms relate to work timing or tasks.
- Reviewing engineering-control performance and maintenance.
- Reassessing products, methods and routes of exposure.
- Examining PPE suitability, fit and use.
- Considering other workers with similar exposure.
- Improving training, supervision or hygiene controls.
- Redeploying where competent advice indicates it is necessary.
- Reporting under RIDDOR where the legal criteria are met.
Do not wait for several workers to be affected before correcting an obvious control failure. Equally, avoid drawing medical conclusions from one unverified questionnaire answer.
How should collective results be used?
Anonymised trends can reveal a weak control that individual cases do not. Compare outcomes by task, department, substance and time without disclosing identities.
A rise in skin symptoms after a glove substitution or process change should trigger investigation even if each case appears mild. Share relevant collective results with workers and safety representatives in a way that preserves confidentiality.
Does health surveillance prove COSHH compliance?
No. A scheme can detect harm after exposure has occurred; it does not prevent exposure. COSHH requires the employer to use the control hierarchy and keep measures effective.
A year of normal results does not justify removing extraction or relaxing procedures. The surveillance method may not detect every effect, and latency can be long.
The Safe Foundry SDS-to-assessment workflow can structure the hazard and control review, while occupational health decisions remain with competent professionals. See the feature overview and help centre for product details.
When should the scheme be reviewed?
Review after product or process change, new health evidence, monitoring results, control failure, symptoms, an abnormal result or a change in worker population. Also check attendance and whether the method continues to be valid.
The practical test is whether the programme connects early findings to prompt control improvement. If records are filed but exposure never changes, the scheme is surveillance in name only.
Frequently asked questions
Do all employees using chemicals need health surveillance?
No. The need follows the COSHH assessment and specific criteria, not chemical use alone. A competent occupational health professional can advise on borderline cases.
Is a questionnaire enough for COSHH health surveillance?
It may be one part of a suitable scheme for a specific hazard, but the method must be valid, repeated as needed and linked to competent interpretation and action.
Can a manager see an employee medical results?
Not without appropriate consent and lawful basis. Managers receive fitness outcomes and control-relevant information, while confidential medical details remain with the occupational health professional.
How long are COSHH health records kept?
HSE gives 40 years as the COSHH retention period for health records. The employer-held health record is distinct from the confidential medical record.
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