Visible crew/equipment: After Station 51 is dispatched to 'man trapped at the rock quarry', when Squad 51 heads through the tunnel-like passageway on the right, it cuts to a shot from behind Mike who's driving Engine 51, and just as the engine heads through the left passageway, we see Squad 51 on the right, and can also see the top of the camera and the other cameraman covered in a dark blanket at the back of Squad 51, as he shoots the footage from that angle.
Other mistake: After Battalion Chief tells Squad 51 to go to the elevator shaft, when Roy, Johnny and Jason enter the building, the DVD subtitles read that Captain Stanley says "Here, the elevator, it's jammed," when in fact it's the Battalion Chief who says that - Captain Stanley is not even with them. Additionally, Johnny asks, "Is somebody in here, Cap?" even though he's addressing the Battalion Chief, not Captain Stanley. Then it's Roy who asks for the oxygen, but subtitles read that Johnny asks for it.
Visible crew/equipment: At the rock quarry, when John is pulling up the stokes Jason is standing to his left, and just as the banister bar breaks in front of John, it's amusing to note that we can see a crew member's hand gripping the back of Randolph Mantooth's pants, at the right side of the screen.
Other mistake: When Squad 51 and the engine company arrive at the rock quarry, in the shot after John tells Jason to get the HT, just as Roy, Captain Stanley and Mike walk towards the right side of the screen, something drops down from the top of the screen, enough to cover the top left corner of the screen area, then gets pulled back up.
Visible crew/equipment: When Jason prevents Johnny from falling at the rock quarry, the outline of the mic transmitter is visible on the back of Jason's shirt (left side) in the overhead shot, as he hoists Johnny onto the platform, Then just after Johnny says that they should get out of there, in the shot of Roy bending over the trapped man, the outline of the mic transmitter is visible on the back of Roy's shirt.
Visible crew/equipment: After Roy tells Jason that he has time to pop up to the orthopedic ward because it's Johnny's turn to cook, when Roy heads out receiving we can see the top of the set over treatment 1, right behind Johnny.
Visible crew/equipment: When Squad 51 arrives at Homer's house, we can see the outlines of the mic transmitter and wire on the back of the old cowboy's shirt.
Continuity mistake: When Brackett is in his office talking to Patsy's manager, he's paged and then told, "Treatment room 2, STAT," and he answers, "On my way," but Brackett doesn't rush to treatment room 2, he goes to room 230 which is Patsy's room, and Early even calls for a code blue in room 230.
Continuity mistake: When Brackett and Morton are with Patsy in her hospital room, there are two closeups of the Datascope 850, but there's an entirely different unit at the foot of Patsy's bed monitoring her EKG, not the Datascope 850. The same thing happens again later, when Brackett rushes in and Early tells him that Patsy was throwing more PVCs.
Continuity mistake: At the rock quarry, after Johnny tells Captain Stanley that they need the Stokes and a jack, Johnny removes his helmet, and while Jason holds Johnny's helmet, Johnny tosses the rope below, but in following shots Johnny's wearing the helmet again.
Continuity mistake: At the start, when Johnny and Roy get back to the station from their run, Roy leaves two cabinet doors wide open when he gets two coffee cups, but in the next shot as he shakes Jason's hand, those two doors are suddenly closed.
Revealing mistake: After Station 51 is dispatched to 'man trapped at the rock quarry', just before Squad 51 heads through the tunnel-like passageway, in the shot from the top of the squad we can see that the lightbar's chrome center and trim have been covered in black, presumably to prevent the reflection of the camera and cameraman, who's riding atop the squad.
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy