Salvage and Overhaul No. 3 Questions taken from Jones & Bartlett Fundamentals of Fire Fighter Skills (3rd Edition) Progress Indicator: Question 3 of 15 3.  Whenever possible, it is best to enter the mine by way of the safest _______________.   (MSHA 3028, p. 4-5) Choices: unobstructed passageway means intake airway point of entry