I guess this is where the experience, if any, of your OIC is paramount. This person needs to be able to carry out a very rapid assessment of the situation, knowing that persons are trapped, or at least inside, and wether the risk is greater than the chance of a successful rescue. Hard call at best of times. As a Firey, I would still want right of refusal. Don't think OIC's would "force" you to enter premesis if you weren't comfortable with it. I would hope most would be prepared to do what they could, within reason and reasonable risk, to save a life - isn't that part of why we joined the service??
This is purely a personal point of view, from someone who has never had to enter a burning biulding, yet!
Some may say, what is a reasonable risk? and that no risk can be considered reasonable. Tell that to the frantic mother who's five year old is still inside.