There are few "LAWS" regarding this issue. Over the years I worked in many different shops. The majority of those jobs couldn't even consider an employee to be free to respond to the "page" and more than that the employee wouldn't be allowed to even carry the pager onto the property. I never felt a need to challenge the right of my employer to set those policies.
In the small towns / rural area that the 3 Fire Districts of Sabine Parish Louisiana cover, there are 3 towns and five villages. Our NSFD encompasses 420 square miles, almost half of the 1020 square miles within the Parish, and covers two of the towns and two villages. We have twelve station areas with 16 station houses and 35 pieces of equipment. We have 14 engines, 16 tanker tenders, 4 service / reserve pumpers and a light rescue. Only two major industries reside here but the three towns have shops and business that are dependent on us for fire protection. We carry a PIAL rating of "6" but got really close to a "5" last rating test.
Of the business where some of our firefighters are employed, there is only one that I know of that gives his employee freedom to respond to a structure fire or a major MVA that requires "Rescue". I have always gone out of my way to compliment that business man and he always comes back "It might be my house or store the next time you get the call" I wish more business felt that way and I wish more people would give praise and publicity to those who business owners who do feel it is their responsibility to the community, to give the Volunteer Fire fighter freedom to respond to important calls.
One other thing for us to remember "If the boss lets you go - do not take advantage of his generosity! If you hear or learn that there are enough responding to cover the call - - turn around and go back to the job that puts food on your table and fon't forget to thank him!