Almost one in five construction sites visited have had enforcement action taken against them following visits from the Health and Safety Executive (HSE).
During a month long initiative, HSE inspectors visited 2,363 sites where refurbishment or repair work was taking place and saw 2,976 contractors.
631 enforcement notices were served across 433 sites for poor practices that could put workers at risk, with 451 notices ordering that work stop immediately until the situation was put right.
The HSE's Chief Inspector of Construction, Philip White, said: 'This initiative has once again shown us that the majority of construction employers do take their responsibilities to their workers seriously.
'However, our inspectors also encountered numerous examples of poor practice, from lack of edge protection on stairwells and scaffolding to unsafe storage of flammable materials and inadequate personal protective equipment. None of these are acceptable on a modern construction site.'
Between 18 February and 15 March inspectors made unannounced visits to construction sites to ensure they were managing high-risk activity, such as working at height.
In addition, checks were carried out on whether there was general good order on site, whether PPE was being used effectively and if welfare facilities were adequate.
During 2011/12 49 workers were killed while working in construction and 2,884 major injuries were reported.
