Visible crew/equipment: After the ambulance arrives at the lion pit, just as the attendants reach the fence where John and Roy are standing, and the stokes is loaded onto the stretcher, we can see the two white tape marks on the ground, where the zoo employee is standing.
Visible crew/equipment: When we hear Station 51 being dispatched to the structure fire at Kiddytime Toy Factory, just as Roy rushes to the squad's door to open it, we can see the reflection of the camera dolly through the squad's windshield as it moves.
Other mistake: During the paint factory fire, when Engine 2 rolls up, we can see the red, large, rectangular vinyl material that is adhered to the front of the engine, with the company number printed on it. There's also vinyl material adhered to the top of the cab as well as the back of the engine with nothing on it, presumably covering the engine company's real number.
Other mistake: When Squad 51 is dispatched to the possible heart attack, while Chet’s at the base station responding to the dispatcher, the lightbar atop Squad 51 has nothing covering the chrome, but en route in the close up there's black tape covering much of the chrome trim.
The Promise - S3-E11
Other mistake: At the very end, when Roy is cleaning the windshield while John's fiddling with the squad’s radio mic, the spray can on the hood of the squad has tape covering the brand name.
Other mistake: When Dixie's on the phone with the suicide attempt, Dixie tells her the date of her own birthday, hoping to get the caller's birthday in return. Then when the caller tells Dixie that the month of her birth is February, while Brackett's listening, they don't contact Early who's with the senior data analyst with that crucial information to help narrow down her identity faster, which was the whole point of Dixie trying to get that information from her.
Other mistake: During the fire at the horse ranch, when Engine 40 rolls up we can see that the engine company's number is covered atop the cab, and the large, red rectangular vinyl material that's adhered to the back of the engine with nothing on it. Presumably covering the real engine company's number.
How Green Was My Thumb? - S3-E17
Other mistake: When Station 51 is dispatched to the fire at the winery, just as Squad 51 rolls up, in this semi-closeup we can see that it's Roy driving and exiting the squad, and also that it's actually Randolph Mantooth's double exiting the squad and getting the drug box from the side compartment. Also fun to note the difficulty the double had just opening the squad's door.
Continuity mistake: While the judge and young lawyer are doing CPR to help, Roy's tearing off strips of tape and placing them on his pants (for IV as usual), then after he asks Johnny, "Were you able to get in touch with Rampart?," in the next shot all those strips of tape have vanished from his pant leg, only to reappear when Roy defibs the patient.
Visible crew/equipment: After Engine 51 rolls up to the scene of Paula's car accident, when Captain Hammer stands up in the engine's cab, the reflection of production equipment is visible on the engine's chrome spotlight.
Visible crew/equipment: At the start, when Squad 51 rolls up on the car accident scene, in the shot from inside the squad we can see the entire area around the wrecked car, and there's only a utility pole, short wood fencing, and trees. When Roy and John are treating Paula, and then removing her from the car, in the overhead shots as the camera faces the wrecked car and 51's rigs, there's a very large rectangular shadow being cast over the car, which is presumably from a reflector screen facing the front of the car.
Heavyweight - S3-E5
Other mistake: When Chet is preparing the lasagna, then tells Johnny that he's preparing 'rutabaga delight' especially for him, the green container of parmesan cheese has tape covering the brand name, though it looks like it's the Kraft brand.
Heavyweight - S3-E5
Continuity mistake: At the start, after Station 51 is dispatched to the apartment fire, when a musician asks Captain Stanley for help removing instruments from the burning building, the next shot showing Truck 98 rolling up is footage from 2x13, "Drivers", during the fire at the Atlas Hotel. We can even see the smoke through the Atlas Hotel's windows, and Squad 51 parked across the street. More footage from the Atlas Hotel fire is shown when Engine 16 rolls up. Additional footage from other episodes are shown as well, when we see helmets and rigs bearing company numbers that were not called to this fire.
Nurse's Wild - S1-E7
Continuity mistake: While Early, Dixie, and Brackett are talking in the hallway about going to lunch, Ellen comes out of the treatment room (opposite receiving) next door to treatment 2 and calls to Dr. Early, but when Early and Ellen walk back into that room, they are now in treatment 3, which is directly opposite from treatment 2.
Cook's Tour - S1-E4
Other mistake: When Johnny and Roy visit the woman they assisted in delivery, they go through the ER's double doors opposite receiving, as if heading upstairs to her room, and soon she even comments that the baby was brought up to her from the ER. Then, when the guys leave her room, Roy pushes open the door on the right, and we can see the ER's treatment 5 and the silver cabinets right up the hallway, so we know that Roy and John were actually in the room just off to the side of the nurses' station in the ER.
Continuity mistake: After Johnny and Roy find the motorcycle and its injured rider, Johnny wraps his arm/shoulder area, but the way it's wrapped - whether or not it's over the shoulder and/or at his waist, and the amount that's wound around his body, significantly differs between shots until they see Vince at the base station.
Visible crew/equipment: After Squad 51 is dispatched to the cliff rescue, when Roy and Johnny board Copter 10 at Rampart, the reflection of the production vehicle/equipment is visible on the glass surface at the helicopter's nose.
Visible crew/equipment: When the police officer who was struck by lightning is wheeled into the ER, just as Dixie, Brackett, and Early walk up the hallway, the two tape marks are visible on the floor right outside the doorway of treatment 2, where Dixie is about to stand. Additionally, we can see the outline of the transmitter wire on the back of Dixie's uniform.
The Wedsworth-Townsend Act - S1-E1
Visible crew/equipment: When Station 10 arrives first on scene at the factory fire, as 10's third rig pulls up and lays the line in the wide shot, at the left of the screen in the background, we can see the hidden second cameraman who is shooting the footage from that angle, of all the rigs pulling in and turning.
The Wedsworth-Townsend Act - S1-E1
Continuity mistake: When the man who was electrocuted is loaded onto 127's snorkel, we can see that he's wearing a white crew-neck undershirt under the denim shirt, but at the ER when his denim shirt is open there's nothing underneath.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.