Phil,
My apologies in advance for a very long (and possibly very boring) post but in discussions like this one (which is an extremely good one by the way) the "semantics" could be very important.
The legal position is that the "employer" (i.e. the company, charity, public body) is its Board of Directors (Trustees, etc.), which accepts responsibility and liability for any task lawfully done on its behalf. This concept is enshrined in Company and Public Law and in the civil law concept of vicarious liability. It is of course a totally different story if an individual carrying out a task on the organisation's behalf deliberately breaks the law (e.g. theft of funds), in which case the individual will be held not to be acting in the "course of his employment". That is why generally, the employer will remain liable for the acts or omissions of its employees, even where it has delegated responsibility for undertaking a task to the employee. In a health and safety context it is why an employee can only be prosecuted for a breach of s.7 of HSWA where it can be shown that the employer has complied with all of its s. 2 HSWA duties.
Messeyshaw,
Why would a company, etc. be referred to as "Responsible Persons" when the organisation is a single legal entity?
I read from your post above that (whether on your advice or otherwise) your clients have delegated "control" of sites to their managers (or others). Article 5(3) of the RR(FS)O has not been tested in the courts, but it is likely that any attempt to by an organisation to delegate liability to an employee in this way would be held to be void by the Courts and the employer would remain liable. The reason is that the manager is an employee of the organisation, which therefore remains liable unless (as I have stated above) the manager goes outside the scope of his employment.
S. 5(3) is designed to apply where responsibility for complying with the Responsible Person's duties has been lawfully delegated (e.g. maintenance of fire detection and alarm equipment to a competent engineer), this would not apply to a company employee.
There is of course Article 23, which imposes a duty akin to that of S. 7 of the HSWA. However, the Fire Safety (Employees' Capabilities) (England) Regulations 2010 impose a duty on an employer not to entrust a fire safety task to an employee unless it is satisfied as to the employee's capability to undertake that task (i.e. the organisation must have complied with all its duties in selection, training, supervision, monitoring and review, to ensure the employee's capability).
On a more general note, a solicitor has a duty imposed by the Solicitors Regulatory Authority to "act in the best interest of his client" at all times unless this duty conflicts with the solicitor's duty to the court. As such, it is incumbent upon any solicitor defending an organisation for a health and safety (or fire safety) breach to provide all the possible defence/mitigation options to the client.
Where applicable this must include advising the client to seek to transfer liability for a breach to a contractor/consultant, where the breach was due to their act or omission. Consultants should therefore be very careful about advising an organisation to do something (or refrain from doing something) unless they understand the full implications of that advice, as it could well come back to haunt them in the future.
Once again, sorry for the long post.
Regards.
DJ