Workers in the factory are workers under the supervision and control of the company - they receive training, operate according to procedures, work in workstations where occupational environmental tests are performed, undergo medical tests and receive personal protective equipment. So close is the familiarity with the workers, that sometimes we also know their families, their joys and disasters and can be aware of moments of inattention.
Contractor employees, on the other hand, are similar to introducing a Trojan horse into the factory. We don't know them, they change with an unknown frequency, we have no control over their work tools, the protective equipment they use (if any), their professionalism, and even if we really want them to work on the premises according to the rules - their commitment to us is questionable, and our control over them is very limited.
For all these reasons, the employment of contractors should be legally regulated before the start of work - starting with the contractual phase which must include, among other things, the correct definitions and an appropriate safety annex, continuing with the appropriate procedures for tracking and documenting the entry of workers, performing appropriate and relevant risk surveys (JSA or TSA), and establishing regulated and effective mechanisms of training and internal factory supervision.
All these activities should be part of an internal enforcement plan of a company that wants to carry out projects with contractors, and also get out of it safely at the end of the road.
These are exactly the things we have been doing for many years - we accompany entrepreneurs and property owners who employ contractors, starting with the stages of the tender and the preparation of contracts, continuing with the formulation of appropriate safety annexes, and continuing with legal support for all stages of the employment of the contractors in view of the importance of maintaining safety and with an attempt to reduce as much as possible the legal exposure of the company and its managers.