A contractor is any person brought in to work for you who is not an employee, or treated as such for health and safety purposes (as may be the case, for example, for someone who works under your direction but is regarded as self-employed or a temporary or agency worker).
Most organisations use contractors to provide a variety of services that their employees aren’t expected to have the knowledge, skills and experience for, or to use up their working hours on, such as cleaning, maintenance, installation, repairs, servicing, transport, security and catering. Their presence on-site may be very brief, for an hour or two, or much longer and possibly spread over days, weeks or months, and could even be permanent (in the case of catering staff and cleaners, for example).
Accidents happen when communication, co-ordination and/or supervision between all relevant parties about the hazards presented by one another’s work activities are absent or ineffective, resulting in a lack of appropriate risk control measures.
There are unfortunately many examples where failures in the client-contractor relationship have caused fires, property damage, injuries, ill health, and even fatalities, leading to the prosecution of both parties.
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.