Visible crew/equipment: When Roy and Johnny are driving in the squad, while discussing Roy's last phone call from Susan, Johnny's lack of tact, etc., and particularly as they're being dispatched to the "possible maternity case," in every shot facing Johnny pay attention to the window behind the guys, because we can see a crew member's right hand, wearing a ring, who's holding a rope while he's riding on the back of the squad.
Visible crew/equipment: When Roy and Johnny are with 110 and are on scene at the downed airplane, as they remove the pilot from the aircraft, the silver fire starting canister used for the stunt is visible under the plane, before it becomes engulfed in flames.
Continuity mistake: When Roy and Johnny are at the construction site with the guy who wants to jump, before Roy walks over to him we see the pompier belt around Johnny's waist has the carabiner hook to his left and the double tongue buckles to his right. Then when Captain Stanley tells Johnny to try and get to the guy from the other side, Johnny's belt is now around his waist the opposite way. In the following shots his life belt flips around a couple more times. Note that their pompier belts have at one side double leather straps which are the two tongue buckles, and the other side has a single strap of leather for the attached carabiner hook.
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy