CDM audit: what should you review on a construction project?

What is a CDM audit?

A CDM audit is a planned review of the arrangements and evidence used to manage health and safety under CDM 2015.

Depending on the stage and purpose of the review, it may cover client arrangements, duty-holder appointments, capability, pre-construction information, design coordination, the construction phase plan, site management, worker engagement, welfare, the health and safety file and project close-out. HSE summary of CDM 2015 duties: HSE cross-duty-holder summary of who does what under CDM 2015, useful for setting the scope of a project review (opens in a new tab)

Is a CDM audit legally required?

No. CDM 2015 does not require a document or process called a ‘CDM audit’.

However, commercial clients must make suitable arrangements for managing the project, maintain and review those arrangements throughout the project, and take reasonable steps to ensure the Principal Designer and Principal Contractor they appoint carry out their duties. A proportionate audit can be one practical way of supporting that assurance. Read Regulation 4 on legislation.gov.uk: client duties in relation to managing projects: suitable arrangements for managing the project including sufficient time and resources, maintaining and reviewing those arrangements throughout the project, and taking reasonable steps to ensure the principal designer and principal contractor comply with their duties (opens in a new tab)

The audit should therefore be treated as a management tool, not as a legal certificate or proof that every CDM duty has been satisfied. HSE commercial client guidance: HSE summary of commercial client responsibilities under CDM 2015, including making suitable management arrangements, making appointments, providing pre-construction information and checking that the principal designer and principal contractor are carrying out their duties (opens in a new tab)

How is a CDM audit different from a checklist?

A checklist is useful for identifying the areas that should be reviewed. An audit goes further by testing the quality and effectiveness of the arrangements.

For example, a checklist may ask whether a construction phase plan exists. An audit should also ask whether the plan reflects the actual project, whether people are following it, whether it is being reviewed as the work changes and whether the arrangements described in it can be seen in practice.

When should a CDM audit be carried out?

There is no prescribed audit frequency. The timing should be proportionate to the project’s duration, complexity, risk and rate of change. HSE L153 guidance: Managing health and safety in construction: practical interpretation of the CDM 2015 duties, proportionate management arrangements and the review of those arrangements, PDF (opens in a new tab)

Useful review points can include:

• After mobilisation, once the project arrangements are operating in practice.
• Before or shortly after the construction phase starts.
• At key design or programme gateways.
• When there is a major change in scope, contractor structure or project risk.
• After recurring inspection findings, incidents or significant concerns.
• Midway through a longer project to test whether arrangements remain effective.
• Before handover to confirm health and safety information and close-out actions are being completed.

Who should carry out the audit?

The person carrying out the audit should understand CDM 2015, the project and the difference between checking a document and testing how a duty is actually being discharged.

The auditor may be part of the client’s assurance function, an internal health and safety team or an independent competent adviser. Independence can help challenge assumptions, but the auditor still needs access to the people and evidence behind the project.

The audit should not transfer legal duties away from the client, Principal Designer, Principal Contractor, designers or contractors. HSE summary of CDM 2015 duties: HSE cross-duty-holder summary of who does what under CDM 2015, useful for setting the scope of a project review (opens in a new tab)

What should a CDM audit review?

The scope should be tailored to the project stage, but a broad project-level audit will usually consider the following areas.

1. Client arrangements and governance

• Are suitable arrangements for managing the project documented and understood?
• Are sufficient time and resources being provided?
• Are roles, responsibilities and escalation routes clear?
• Are the management arrangements being maintained and reviewed as the project develops?
• Is the client obtaining enough information to make sure the Principal Designer and Principal Contractor are carrying out their duties?

2. Duty-holder appointments and capability

• Were the Principal Designer and Principal Contractor appointed where required?
• Were appointments made in writing and early enough to influence the project?
• Is the scope of each appointment clear?
• Was relevant capability considered before appointment?
• Do the people and organisations performing the roles still have sufficient resources and capability for the project as it now stands?

3. Pre-construction information

• Was relevant pre-construction information identified and issued early enough?
• Does it address known site, structure, service, access and project constraints?
• Are gaps in information being identified and closed?
• Is new information being communicated as the project develops?

4. Design management and Principal Designer coordination

• Are designers considering foreseeable health and safety risks as part of design decisions?
• Are significant design risks being eliminated or reduced where reasonably practicable?
• Are design interfaces and unresolved issues being coordinated?
• Is the Principal Designer actively planning, managing, monitoring and coordinating the pre-construction phase?
• Is relevant design information reaching the Principal Contractor at the right time?

5. Construction phase plan and mobilisation

• Was the construction phase plan prepared before construction began?
• Does it reflect the actual project rather than generic company procedures?
• Are key site-management arrangements clear?
• Are welfare, induction, access, traffic, emergency and coordination arrangements in place?
• Has the plan been reviewed and revised where the project has changed?

6. Principal Contractor and contractor management

• Is the Principal Contractor coordinating the construction phase and contractor interfaces?
• Are contractors planning, managing and monitoring the work under their control?
• Are site rules, inductions, supervision and worker information suitable?
• Are workers being consulted and able to raise concerns?
• Are contractor performance and recurring issues being followed up?

7. Welfare and site arrangements

• Are suitable welfare facilities available and maintained?
• Are access and unauthorised-entry controls effective?
• Are site traffic and pedestrian arrangements working in practice?
• Are housekeeping, storage and work-area controls being maintained?

8. Cooperation and information flow

• Are client, Principal Designer and Principal Contractor information exchanges working?
• Are contractors and designers cooperating where their work interfaces?
• Are significant actions assigned to owners and tracked to closure?
• Are changes reaching the people who need to act on them?

9. Health and safety file and handover

• Is the health and safety file being developed where required?
• Is useful information being captured throughout the project rather than left until the end?
• Are residual risks and future-work information being communicated clearly?
• Are close-out actions and information-transfer responsibilities understood?

What evidence should an auditor sample?

Evidence should be proportionate and selected to test the arrangements rather than simply increase the amount of paperwork reviewed. HSE L153 guidance: Managing health and safety in construction: practical interpretation of the CDM 2015 duties, proportionate management arrangements and the review of those arrangements, PDF (opens in a new tab)

• Written appointments and role scopes.
• Capability / appointment assessment records.
• Project programmes and mobilisation plans.
• Pre-construction information.
• Design review and coordination records.
• Design risk / issue records where used.
• Construction phase plan and revisions.
• Site induction and worker-briefing records.
• Inspection and assurance records.
• Meeting minutes and action trackers.
• Contractor-performance information.
• Welfare and site-arrangement checks.
• Health and safety file development records.
• Incident, near-miss or recurring-issue information where relevant.

Why interviews matter

Documents show what the project says should happen. Interviews help test whether people understand their role and whether the arrangements are actually operating.

Useful questions may include:

• Who is responsible for this decision or action?
• How are design risks escalated and resolved?
• How do contractors receive information that affects their work?
• How are changes to the project reflected in the construction-phase arrangements?
• How do workers raise concerns?
• How does the client know the Principal Designer and Principal Contractor are carrying out their duties?

Why site observation matters

A site walk can show whether documented arrangements match reality.

The audit should not become a general safety inspection of every hazard on site, but it can test whether important CDM management arrangements are visible in practice — for example welfare, site access, induction controls, coordination between contractors, implementation of agreed actions and consistency with the construction phase plan.

How should audit findings be graded?

CDM 2015 does not prescribe an audit-scoring system.

A project may use categories such as compliant / improvement needed / significant gap, or another internal grading system, provided the meaning is clear and the scoring does not replace professional judgement.

The most useful finding explains what was expected, what evidence was seen, what the gap is, why it matters and what action is required.

Example CDM audit finding structure

How should corrective actions be managed?

An audit has little value if findings are issued and then forgotten.

Each corrective action should have a clear owner, proportionate target date and evidence of closure. Higher-risk or recurring findings may need escalation to project or client governance rather than being left as routine site actions.

Closure should confirm that the intended improvement has actually been implemented. Producing a revised document may be part of the action, but it is not always enough on its own.

Should every audit cover the whole of CDM?

No. A focused audit can be more useful than repeatedly checking the same full list.

For example, an early audit might concentrate on client arrangements, appointments, capability and pre-construction information. A later construction-phase audit may focus on Principal Contractor arrangements, contractor coordination, site induction, welfare, construction phase plan implementation and information flow.

Common CDM audit mistakes

Auditing paperwork instead of practice

A project can hold all the expected documents while the arrangements described in them are not being implemented.

Using one generic audit for every stage

The most useful scope changes as the project moves from design through mobilisation, construction and handover.

Treating every finding as equally important

Actions should be prioritised according to risk, legal significance and the effect on project control.

Writing vague findings

A statement such as ‘improve CDM compliance’ gives the project little help. Findings should explain the gap and required action.

Closing findings on document production alone

The auditor should check whether the underlying arrangement has changed in practice where that is what the finding required.

Ignoring recurring themes

Repeated contractor, design or coordination issues may indicate a systemic problem rather than isolated findings.

Turning the audit into a site inspection only

Site conditions matter, but CDM assurance also covers client, design and project-management arrangements.

Using a score as the final answer

A percentage can summarise results, but it cannot replace an explanation of material gaps and priorities.

CDM audit checklist

• Define the purpose and project stage before starting.
• Set a proportionate scope rather than auditing everything by default.
• Review key documents and sample evidence.
• Interview people carrying the relevant duties.
• Observe enough of the project to test implementation.
• Distinguish legal or material gaps from minor administrative improvements.
• Record clear evidence for each significant finding.
• Give corrective actions owners and due dates.
• Escalate recurring or high-risk findings appropriately.
• Verify closure rather than accepting a revised document automatically.
• Use trends from repeated audits to improve wider project or supplier assurance.

CDM audit vs inspection

An inspection usually focuses on conditions, activities and controls that can be observed at a particular time. A CDM audit is broader: it tests the management system, duties, decisions and evidence behind the project.

The two complement each other. Inspection findings can feed into the audit, while audit findings may identify management weaknesses that need targeted inspection or follow-up.

CDM audit vs compliance checklist

The Aptoris CDM compliance checklist is designed as a quick project-level prompt covering the main areas that should be present.

A CDM audit uses those areas as a starting point and asks for deeper evidence: what is happening, who is responsible, whether arrangements are effective and whether actions have actually been closed.