Subcontractors · Best Practice · Pre-Construction

Health Questionnaire and Medical Declaration

A confidential health questionnaire to identify pre-existing conditions that may be relevant to construction work.

Last reviewed: 29 March 2026 — This guide reflects UK law as of this date. MHSWR 1999 remains current with no amendments enacted as of 29 March 2026. Next scheduled review: 29 March 2027.

Legal basis	MHSWR 1999 + COSHH 2002 + Equality Act 2010 + UK GDPR
Purpose	Identifies pre-existing conditions relevant to project hazards — not a general health check. Focus on respiratory, skin, hearing, musculoskeletal, conditions affecting height work.
Not pre-employment	Under Equality Act 2010, health questions before a job offer are generally prohibited. Complete AFTER appointment.
COSHH health surveillance	For workers exposed to specific COSHH hazards, the questionnaire provides the baseline.
Equality Act	Disclosure must trigger consideration of reasonable adjustments, not exclusion.

1. Health Questionnaire — Safety-Relevant Baseline, Not General Medical Screen

The health questionnaire is a targeted safety tool. Questions should be limited to information the employer genuinely needs for safety purposes. It is not a general medical screen, and collecting health information beyond what is necessary for safety is both disproportionate and potentially unlawful under UK GDPR.

For workers exposed to silica dust, ask about pre-existing respiratory conditions. For vibrating tool users, questions about Raynaud's disease or numbness in the hands are relevant. For workers at height, questions about vertigo, epilepsy, or medications causing dizziness are appropriate. For workers in noisy environments, questions about pre-existing hearing loss establish a baseline for future monitoring.

The questionnaire should be linked to the project's hazard profile. If the project involves no COSHH hazards, extensive questions about chemical sensitivities are unnecessary. If the project is entirely at ground level, questions about height-related conditions are irrelevant. Tailoring the questionnaire to the actual hazards demonstrates proportionality under both MHSWR 1999 and UK GDPR.

Post-appointment only

The Equality Act 2010 generally prohibits asking health questions before a job offer — health questionnaires must be post-appointment and safety-focused.

2. Health Questionnaire — Suggested Content

Section	Detail
Worker details	Full name, date of birth, employer, trade/role, project name
Project-specific hazards	List of hazards identified from project risk assessment that the questionnaire is designed to address
Respiratory	Pre-existing respiratory conditions (asthma, COPD, previous pneumoconiosis); relevant where silica dust, wood dust, welding fumes, or other respiratory hazards are present
Skin	Pre-existing skin conditions (dermatitis, eczema, psoriasis); relevant where cement, resins, solvents, or other dermal hazards are present
Hearing	Pre-existing hearing loss, tinnitus, or use of hearing aids; relevant where noise exposure exceeds lower exposure action value (80 dB(A))
MSDs / vibration	Pre-existing musculoskeletal conditions, Raynaud's disease, carpal tunnel syndrome, numbness or tingling in hands/arms; relevant where vibrating tools or heavy manual handling are required
Height work	Vertigo, epilepsy, balance disorders, or medications causing dizziness; relevant where work at height is required
Medications	Current medications that may impair ability to work safely, operate machinery, or affect emergency treatment
GDPR consent	Explicit consent for processing health data as special category data under UK GDPR, with privacy notice explaining use, retention, and rights
Worker signature	Signed declaration that information provided is accurate, with date

3. Common Mistakes

Asking general health questions unrelated to the specific hazards

The questionnaire must be proportionate to the project hazards. Asking about conditions that have no bearing on the work being performed collects unnecessary personal data and may breach UK GDPR data minimisation principles. Questions should be traceable back to a specific hazard identified in the project risk assessment.

Completing health questionnaires before appointment

The Equality Act 2010 s.60 generally prohibits asking health-related questions before offering a person work. Health questionnaires must be completed after appointment, not as part of the recruitment or selection process. The only exceptions are where health questions are necessary to determine whether the applicant can carry out a function intrinsic to the role.

Using responses to refuse appointments without exploring adjustments

A worker who discloses a pre-existing condition must not be automatically excluded. The Equality Act 2010 requires the employer to consider whether reasonable adjustments can be made to enable the worker to carry out their role safely. Exclusion without exploring adjustments is unlawful discrimination.

Not treating questionnaire data as special category health data

Health questionnaire responses are special category data under UK GDPR Art 9. They require an additional lawful basis beyond Art 6 — typically explicit consent or employment obligations. They must be stored securely, with restricted access, and retained only for as long as necessary.

Not informing workers how data will be used

Workers must receive a clear privacy notice at the point of collection explaining what data is being collected, why, the lawful basis, who will have access, how long it will be retained, and what rights the worker has. Without this, the processing does not meet UK GDPR transparency requirements.

4. Frequently Asked Questions

When is health surveillance required under COSHH?▾

Health surveillance is required under COSHH 2002 Reg 11 when workers are exposed to hazardous substances with a reasonable likelihood of identifiable disease or adverse health effect. Common triggers in construction include exposure to silica dust, asbestos, isocyanates (spray foam, paints), wood dust, vibration (HAV), and noise. The health questionnaire provides the initial baseline against which future surveillance results are compared.

Who reviews the questionnaire responses?▾

A competent person — typically an occupational health nurse or physician. Line managers and supervisors should not review detailed health information unless they have been specifically trained and authorised to do so. The reviewing clinician advises the employer on fitness for specific tasks, without disclosing the underlying medical detail.

Does the questionnaire need updating if the worker's health changes?▾

Yes. Workers have an obligation under HSWA 1974 s.7 to take reasonable care of their own safety. If a worker develops a new condition relevant to their work hazards, they should complete an updated questionnaire. Employers should remind workers of this obligation periodically, for example at toolbox talks or periodic reviews.

What happens to health questionnaire data when the worker leaves?▾

For long-latency occupational disease data (e.g. COSHH health surveillance records for silica, asbestos, or noise exposure), retention is 40 years from the last entry under COSHH 2002 Reg 11. For other health questionnaire data, retain for 3 to 6 years post-project to cover potential civil claims. After the retention period, data must be securely destroyed.

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