Thanks Mihai.
Used to be something roughly similar in Great Britain (with parallel requirements for Northern Ireland) written into the Construction (General Provisions) Regulations 1961, but it was revoked (I can't remember exactly when).
Section 1(2) of the Health and Safety at Work etc Act 1974 prohibits changes to subordinate health and safety legislation that would have the effect of reducing standards of health and safety that have been achieved.
Fairly easy if the implicit requirements of the Act are to ensure that health and safety is an integral part of the management function to justify getting rid of prescriptive requirements for numbers of Safety Officers per X people on site. Such requirements become counter-productive to the fundamental goal.
So, instead, in the U.K. it's for key players in construction projects (clients, contractors and others) to think about risks, how to control them and then to think about the competencies that managers, supervisors and workers need, and what sort of health and safety advisory resources those people might need to call on.
Those competencies and HSE resources will vary depending on the nature of the project(s), but as a broad brush principle, if the managers and supervisors own health and safety and are competent to do so, then you SHOULD need fewer health and safety advisers.
BUT those health and safety advisers will probably need a greater understanding of risks and possible controls than the managers and supervisors so that they can help out particularly in the areas where the controls are NOT prescribed (or prohibited) in black and white.
As example, in many legislatures, the height from which you could fall before protective measures is often set out in specific legislative terms (we've moved beyond that in the U.K.), and the specifics of what needs to be done are almost entirely directed. Guard-rail at specified height, toe-board also at specified height, possibly intermediate protection. Conversely, for many risks, even if some specifications might be incorporated into law (e.g. a maximum exposure standard for an airborne contaminant) there may be much more flexibility as to how to achieve this.
Similarly, flexibility is written into EU Directives on health and safety. A few prohibitions, a few YOU MUST DO THISs, but mostly a requirement to assess the risks and control them (to a standard that might be specified and/or qualified).