Deliberate mistake: During the rescue of the car at the top of the draw bridge, The Boat approaches and radios in to say that they have a diver standing by. Then after Johnny shouts, "Are you all right?" the rescue boat is shown again, but this time it's a flipped shot - note that everything is reversed from the prior shot.
Continuity mistake: When Squad 51 and the ambulance arrive at Rampart with the father and unconscious diabetic son, the type of ambulance that backs up to the ER entrance is a station wagon, but in the interior shot from Rampart the ambulance type is a truck.
Visible crew/equipment: When Johnny and Roy are at the home of the pregnant woman who was shot, the bulging outline of the mic transmitter is visible on the back, left side of Johnny's shirt.
Daisy's Pick Blind Date - S4-E7
Visible crew/equipment: When the unconscious little boy is loaded into the ambulance, we see the actors' chalk x marks on the ground, where Roy, the boy's father, and mother are all standing.
Visible crew/equipment: After Cora is rescued from the cactus patch, when Harry annoys her and tells her to keep a stiff upper lip while she's lying on the gurney, the reflections of crew members and two reflector screens are visible on Harry's red bike helmet.
Visible crew/equipment: When Johnny and Roy help Cora crawl along the ladder from the cactus patch located in a secluded area, just as Johnny tells her to take it nice and slow, the camera moves a bit too far to the left and then shifts back to the right, but not before we are able to see a crew member, equipment and a large patio-style umbrella.
Visible crew/equipment: When Roy treks across the ladder to get to the woman in the cactus patch, the outlines of the lav mic transmitter and wire are visible at the back, right side of Roy's shirt. Then, when Johnny's on the Biophone with Rampart, the outline of the mic transmitter is visible at the back, left side of Johnny's shirt.
Visible crew/equipment: At the liquor store shooting site, when the second gurney is loaded into the ambulance, the outlines of the mic transmitter and wire are visible on the back, left side of Johnny's shirt.
Visible crew/equipment: After the sniper surrenders, Captain Stanley instructs Engines 12 and 51 to come to the rear of the building, and a few shots later the camera moves alongside Engine 12 as it's turning the corner. In this specific shot, up ahead we are able to see set lighting (including moleeno-style array lights), equipment, crew and actors (in the blue paramedic uniforms), some sitting on chairs in front of the parking attendant's booth (which was shot at by the sniper during the scene).
Continuity mistake: When Johnny and Roy are treating the officer, while hiding between the bakery truck and car, the sniper fires at them which leaves multiple bullet holes on the side of the truck. However, when Vince talks to the Sergeant on the handie-talkie and then fires the tear gas, all the bullet holes on the truck are gone, but they soon reappear.
Visible crew/equipment: After the police officer is shot by the sniper, when Roy and Johnny run with their equipment and duck down behind the squad car, the outlines of the mic transmitter and wire are visible on the back of the Sergeant's shirt, as Johnny and Roy are given flak vests.
Continuity mistake: The window from which the sniper is firing sustains damage with broken glass panes, but then the glass panes are whole and intact, and then they are broken again.
Visible crew/equipment: When Roy and Johnny are with the sick dancer at the bar, the outlines of the mic transmitter and wire are visible on the back of Roy's shirt.
Visible crew/equipment: When Station 51 responds to the photographer who fell in the lion's pit, the outlines of the lav mic transmitters and wires are visible on the backs of Johnny's and Roy's shirts.
Visible crew/equipment: After Art tells Johnny that a film about paramedics is passé, but he'll invite him to the doll movie premiere, Johnny walks over to the ambulance, and the outline of the mic transmitter is visible on the back of Roy's shirt, at his right.
Continuity mistake: Roy and Johnny move a barking dog, who is tied up in front of a hermit's rock-faced cave, and retie the dog to a branch in some bushes, but in following close-ups of the dog he is still tied up at the original spot.
Continuity mistake: When Chet quickly takes off his turnout coat, one of the sleeves is inside out when Johnny uses it on the dog, but then both sleeves are right-side out while he and Roy are trying to subdue the dog.
Continuity mistake: When the boy who ingested ant poison is laid down on the gurney, the safety belt is wound around the gurney's side bar and clasped, but when exiting the house and loaded into the ambulance the safety belt is directly around the boy.
Continuity mistake: When Johnny goes to the closet to get the mop, because he's 'latrine officer of the day', he gets hit by the phantom, and all the guys run out of the kitchen to see Johnny wet again, so when dispatch drops the tones they all head for the vehicles and Captain Stanley removes his jacket. Then next shot all the guys are running out of the kitchen, as if they were all still there, and Stanley is wearing his jacket.
Other mistake: When Battalion 5 orders Copter 10 and Copter 14 to make an air drop on Jawbone Canyon, it cuts to a shot of Copter 14 taking off. This is the same shot used in S3, E6, "Snakebite", when 85's guys tank Copter 14 in order to make a water drop where the teenagers' car is on fire down below.
Answer: It is standard practice to wet down driveways so that they stand out in a long shot.
stiiggy