Other mistake: At the chemical plant, when Captain Stanley gets to the roof and realizes they have to shut off the main valve, over the HT he says, "Engine 8, HT 51, shut off the power..., Engine 15 supply Truck 8...," but the weird subtitles read, "Engine 80, Team 51, shut off the power..., Engine 15, Supply Truck 80..." Then a bit later Captain Stanley tells Mike over the HT, "Engine 51, HT 51, charge the line," but the subtitles read, "Engine 51, Team 51, start your line." Then as soon as Mike charges the line, Captain Stanley tells Roy and Chet, "Okay, full fog, full fog...," but again the weird subtitles read, "Okay, hold strong, hold strong."
Visible crew/equipment: After Station 51 is dispatched to the fire, a dumpster fire already put out by Phyllis, when Mike parks the engine, the reflection of crew members are visible on the jumpseat window, and the location's array lighting is visible on the engine's surface.
Other mistake: When the patient with the heart wound is brought to the ER, the anesthesiologist brings the cart with a ventilating unit close to patient, then there are two closeups of Bird's Mark 4 unit and the bellows housing showing inflation and deflation, and on the bellows unit it reads "Animal Anesthesia Ventilator" made by Bird. This is also the same closeup we see of the ventilator unit in 4x18, "Prestidigitation," during the surgery on Brackett's father.
Other mistake: When Roy and Johnny are with the victim who has a projectile in his heart from a lawn mower, Brackett asks for an EKG strip and there's a closeup of the Datascope monitor, even though the Datascope is not actually in the ER's base station room (it's also still in the squad at this point). Also interesting to note, when Brackett walks out of the base station and tells Early about the heart wound, Early turns the medical chart he's holding at an angle, looks down at it and it appears that he's reading his line from the chart. Then when the ambulance arrives at the scene, the stethoscope is around Johnny's neck, then it's back around Roy's neck as Johnny's lifting the patient, then it's gone from Roy's neck, and then Johnny puts it back around Roy's neck.
Visible crew/equipment: At the chemical plant fire, when Gage is covered in the flammable pentane, Chet hoses him down. When Marco says "John, you better stay here, " Chet and Marco head off. In the next shot, when the camera pans quickly to the left of the blaze, one crew member wearing jeans and a white shirt stands behind the firemen, and another crew member wearing a grey shirt crouches at the side.
Visible crew/equipment: At the chemical plant fire all the plant personnel are evacuated. When Gage yells that one of the valves blew, and that he's covered in the flammable pentane, the camera spins around and a crew member is visible on the right side of the screen, just as Captain Stanley and DeSoto walk up and pass him.
Visible crew/equipment: After inspecting Davey's Dogs, when John and Roy head to the squad discussing how only a total idiot would buy the stand, the reflection of the location's array lighting is visible on the squad's surface, and the reflection of the camera dolly can be seen on the chrome spotlight.
Visible crew/equipment: During the fire at the chemical plant, a couple of shots after we see Captain Stanley walking between Roy and Chet as they're manning two hoses on the roof, we see a shot of Engine 15 as it heads toward the camera and then drives past it, and the reflection of array lighting is visible on the engine's surface.
Visible crew/equipment: When Squad 51 is dispatched to the baby with difficulty breathing, in the wide shot when the squad pulls into the driveway and heads to the front of the house, the cameraman steps out of the shadows on the right side of screen and walks toward the squad (then it cuts to the footage he was shooting), and in the next shot as the moving camera closes in on the squad in front of it, the cameraman's shadow becomes visible on the tree and house.
Continuity mistake: When the patient with the heart wound is brought to the ER, he's wheeled into treatment 2, which has a window on its door, and is on the side of the hallway with the yellow line closest to it. Later we see treatment 1 twice, when Vince brings in the burglary suspect with a bullet in his leg, and also when John and Roy rush the baby to the ER. They used the same room as treatment 1 and treatment 2, but there are just two treatment rooms on that side of the hallway and only one of them has a window on its door - the one that's opposite the nurses' station, treatment 1.