Anyone engaging contractors has health and safety responsibilities, both for the contractors and anyone else that could be affected by their activities. Contractors themselves also have legal health and safety responsibilities. Make sure everyone understands the part they need to play in ensuring health and safety.
Use of contractors in itself does not result in poor health and safety standards, but poor management can lead to injuries, ill health, additional costs and delays. Working closely with the contractor will reduce the risks to your own employees and the contractors themselves.
Remember that contractors may be at particular risk - they may be strangers to your workplace and therefore unfamiliar with your organisation's procedures, rules, hazards and risks. Even regular contractors may need reminding. The level of control needed will, of course, be proportionate to the complexity of the task.
On sites with major accident hazards, consider turnarounds and span of control -
given the potentially very high numbers of contractors on-site (compared with the numbers in routine operations).