Where work is carried out at height, employers must take suitable and sufficient measures to prevent anyone falling a distance liable to cause injury. A dedicated assessment is usually warranted on higher-risk sites: routine work involving motorised gantries and cradles, or regular abseiling operations.
The assessment is completed against Regulation 3 of the Management of Health and Safety at Work Regulations 1999 and the Work at Height Regulations 2005. The site visit begins with a review of relevant paperwork and existing procedures, then the risks are assessed during a survey. As a minimum we look at the equipment used, including suitability, condition, servicing, testing and maintenance; the planning and organisation of work at height activities, with a full review of risk assessments and method statements for suitability and sufficiency; the competency of contractor organisations and operatives where their work is witnessed; and the records and logbooks associated with work at height.
The report identifies the areas checked and how the site performed against each, not only the failures. That gives you evidence of what is working as well as what is not, which matters when you are asked to demonstrate the state of your controls rather than just your defect list.
A report that states its own exclusions plainly, so nobody mistakes an unassessed area for a safe one.