Continuity mistake: After Squad 51 gets back to the station, Roy and Johnny remain in the squad discussing Roy being the coach, and when the dispatcher drops the tones, we see a closeup of five pair of legs rushing out of the kitchen, even though we should only be seeing four pair of legs, since Roy and Johnny are already in the squad.
Continuity mistake: When Johnny and Roy are heading to the parade in The Old Engine, and get sidetracked dealing with a fire rescue, they are wearing the old-style shirts with a ten-button, square bottom bib front, with five buttons on each side. When Captain Stanley laughs at them on the roof, their shirt style differs in the close-up, it's now a nine-button, pointy bottom bib, with four buttons on each side and one button at the bottom point.
Continuity mistake: While on the way to the parade in The Old Engine, when Johnny and Roy deal with the fire rescue and reach the roof, Johnny has a rope bundle swung across from his left shoulder to his right hip. However, in the next shot as they run across the roof, the bundle is now swung from his right shoulder to left hip, and the rope is also bundled differently.
Continuity mistake: When Roy and Johnny are driving to the parade in the fixed up old engine, they repeatedly switch between the road's right lane and left lane, depending on the camera angle.
Continuity mistake: When Roy and John are at the nurses' station talking to Brackett and Dixie about The Old Engine, at the bottom right corner of the screen we can see the patient's metal clipboard chart being held, before Early even walks over to the nurses' station holding a chart. Then when Early does walk over he stands to Brackett's right, but in shots facing Dix and Johnny we still see that chart being held, where Roy is supposedly standing, not Early. Additionally, the charts hanging on the chart holder change/vanish between shots.
Continuity mistake: While Johnny, Roy, and Vic try to outrun Charlene inside Stage 3, after heading down the ladder, when Roy opens the door to find Charlene standing there, Johnny's holding the red extinguisher in his right hand and the nozzle in his left hand, but next shot they've switched hands.
Continuity mistake: When Roy and John are talking to Vic at his party, his manager's cigar changes length repeatedly, from short to long and back again, depending on the camera angle.
Continuity mistake: When Dixie tells Roy and John that Vic wants to see them the guys walk into treatment 2, but in the shot from inside the room we can see that they're actually in treatment 3, on the opposite side of the hall.
Continuity mistake: After Roy and Vic run out of Stage 3, when Johnny backs up and bends down, we can see Charlene, the bear, on all fours, then in the next shot the bear is walking on her hind legs toward the door, but in the next shot from behind Johnny the bear is still on all fours and further back again.
Transition - S4-E15
Continuity mistake: When Gil's in the basket ride at the amusement park, while Captain Stanley swings the line that Johnny's hanging on, in the closeups the open cage door is facing Johnny, but in the long shot looking up the basket's open door is on the opposite side, and Johnny would not have been able to enter it as easily.
Transition - S4-E15
Continuity mistake: When Roy walks into the ER with the chemical burn patient they rescued from a kitchen filled with hydrogen sulfide, Dixie tells them treatment 1 which has a windowless door, but in the shot from inside the room the door has a window, and we can tell it's treatment 3 they're in.
Transition - S4-E15
Continuity mistake: After Brackett and Johnny try to convince Gil that he's not responsible for the MI patient's death, when Johnny walks out of the treatment room he says he's going to check on Roy, and as he opens the door we can tell that he's in the room across from the nurses' station. Then when he and Roy leave the treatment room where Early had examined Roy, we can see that it's the very same treatment room that Johnny had just been in with Brackett.
Transition - S4-E15
Continuity mistake: When Gil is assigned to ride along with Squad 51, en route to the incidents there are only two people seated in the squad in the shots shown.
Transition - S4-E15
Continuity mistake: After Gil and Johnny have lowered the man from the amusement park ride, Gil, who's wearing the backpack, rappels down first and reaches the ground. Then when Johnny hooks in and rappels down, there's a shot of what is supposed to be Johnny rappelling down, but it's actually a shot of Gil, because it was Gil who was wearing the backpack.
Smoke Eater - S4-E16
Continuity mistake: When John and Roy are with the possible MI, while Roy's setting up the IV bag John's on the Biophone with Rampart, and after Brackett orders the IV TKO with MS, we see that Roy's pant leg has nothing on it, but then it cuts to the closeup and suddenly there are strips of torn tape (for IV as usual) on Roy's pant leg.
Smoke Eater - S4-E16
Continuity mistake: While John and Roy are treating the possible MI, when John's on the Biophone with Rampart his watch reads 5:10, but after the patient goes into V-fib John's watch reads 2:45.
Smoke Eater - S4-E16
Continuity mistake: When Station 51 is dispatched to the structure fire including a chemical lab, Johnny and Roy put on SCBA tanks with distinctive markings/stickers before going in, but those tanks change while inside and when they exit with the victims of chemical smoke inhalation.
Smoke Eater - S4-E16
Continuity mistake: After Dr. Early is called a miracle worker and then again tries unsuccessfully to get the apple from the machine, it cuts to Squad 51 pulling backwards into the apparatus bay, and the engine we see parked in the bay is the Crown from the first two seasons, not their current Ward LaFrance.
Smoke Eater - S4-E16
Continuity mistake: When Billy's mother waits in the hallway while Early examines Billy, the window behind her is on the same side as the ER's receiving entrance. Note that outside the window there's a blue metal shade at the top, which does not exist in any exterior shots of that side of the ER.
Smoke Eater - S4-E16
Continuity mistake: When Captain Robertson voices his disapproval about the paramedics, while the guys are in the kitchen eating, there are plates, cups, saucers, and utensils on the table. Then Station 51 is called to respond to a child trapped at the storm drain, and when the guys run out of the kitchen we see behind them that the table is now bare.
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy