I would agree with much of what you say Hammer1 but to me the proof is in the pudding.
It appears to me that people outside the building site are currently being placed at risk as a result of a fire on some sites due to the radiated heat flux and smoke.
I believe the problem is caused by the differences in the overlapping legislation. The CDM Regulations covering fire safety focus ONLY and specifically on the people on site. Any consideration of the risk to people off site arises only as a result of Section 3 of the HASAWA 1974.
The Fire Safety Order very clearly covers All Relevant Persons. Where the HSE are the Enforcing body under the Fire Safety Order, article 47 does NOT apply so actually they have a double barrelled gun in their arsenal.
But in carrying out their enforcement duties unless they broaden their focus under the CDM Regs to include consideration of Section 3 of HASAWA (and which specific CDM Regulation would they apply to deliver this?) the Fire Safety Order is the only effective legislation to protect Persons outside the curtilege of the site.
All in my opinion of course, and stated in the interest of discussion and understanding , and not wanting to imply criticism of any particular agency or event. (Had a couple of emails from people who think I am pointing fingers at them. This is absolutely NOT the case I have been banging on about the CDM Regs and Fire Safety since the last ACOP was published in 2007)