Building Construction No. 2 Questions taken from Jones & Bartlett Fundamentals of Fire Fighter Skills (3rd Edition) Progress Indicator: Question 4 of 15 4.  Air locks are to be used by mine rescue teams Choices: in place of a fresh air base when closing a door or building a bulkhead behind which conditions is not definitely known before opening a barricade in bad air behind which trapped miners might be located as refuges where they can remove or repair their breathing apparatus all of the above