Most contractor prequalification packs ask for the same dozen things: insurance certificates, a safety policy, training records, an accident frequency rate. All of it is worth having. Almost none of it predicts how the crew that arrives on your site will behave once they are there.
Why the usual questions underperform
A safety policy is a document about intentions. Every company that has one can send it to you. An accident frequency rate is a number whose denominator you cannot see and whose reporting culture you cannot audit — a contractor with a genuinely open reporting culture will often look worse on paper than one where nobody writes anything down. And a training matrix records that somebody attended a course, not that the man on the scaffold tomorrow was in the room.
None of this is an argument for skipping them. It is an argument for not stopping there.
Questions that carry more information
- Who specifically will be on site, and what is their turnover? A contractor who cannot name a supervisor two weeks out is going to send whoever is free. High crew turnover undoes site induction faster than any training budget can replace it.
- Show me a method statement you wrote for a job like this one. Not a template — an actual one, with the site's own hazards in it. Generic documents are the clearest signal you will get that the hazards were never thought about.
- Tell me about a job that went wrong and what changed afterwards. A contractor who has never had anything go wrong is either very new or not telling you. The value is entirely in the second half of the answer.
- What would make you stop work here? The answer reveals whether stopping is a real authority held by the crew or a decision that has to travel back to an office.
- How do you subcontract? The company you assessed is frequently not the company that turns up. Ask what proportion of the work goes to others and what they check before it does.
Prequalification is not a one-time gate
The most common structural failure we see is treating prequalification as an event: passed in January, filed, never revisited. Competence is a property of the current crew, not of a folder. Re-check it when the crew changes, when the scope changes, and after any job where something had to be improvised.
Match the depth to the risk
A painter and a company entering your confined spaces should not face the same questionnaire. Grade the process by consequence: light-touch for low-hazard work, and genuinely searching — including a site visit and a conversation with the people who will hold the tools — for hot work, confined space entry, work at height and anything on live systems.
The paperwork tells you a company is insurable. The conversation tells you whether they are safe.
Is Your Contractor Assessment Asking the Right Questions?
Our HSE team builds prequalification and contractor control systems graded by real risk, with assessment criteria your people can apply consistently and audit trails that hold up when something goes wrong.
Explore HSE Services