Visible crew/equipment: When Roy, Johnny, and Captain Stanley are in the collapsing house trying to rescue the man trapped under it, the outline of the mic transmitter is visible on the back of Roy's shirt when he's leaning over on his knees, as Johnny cuts the carpet. Then the outline of Johnny's mic transmitter is visible on the back of his shirt, when he's below the house.
Visible crew/equipment: When Engine 51 arrives on scene, to join DeSoto and Gage, the guys pull on the pilot to free him from the sailplane, and the outlines of the mic transmitter and wire are visible on the left side of Gage's shirt.
Visible crew/equipment: After Mr. Howarth confronts his son about the pills his daughter took, when Dixie walks up and tells him that he can see Monica, the actor's tape mark is visible on the floor, at Dixie's feet.
Visible crew/equipment: When Roy and Johnny are working on freeing the man trapped in the vehicle, and then when they are taking his vitals, the outlines of the mic transmitters and wires (running up toward their shoulders) are visible on the back of Roy's and Johnny's shirts. The mic transmitter's outline is also visible on the left side of Christy's sweater, below the waistline.
Visible crew/equipment: When Roy and Johnny are walking down the hallway at Rampart, Roy asks Dixie for some supplies, just before Johnny spots Sheila doing uncover work, the two white tape marks are visible on the floor just behind him.
Visible crew/equipment: During the rescue of the unconscious boy stuck within the tree, when DeSoto climbs the ladder to begin chiseling at the tree, the outline of the mic transmitter is visible on the back of DeSoto's shirt.
Visible crew/equipment: When DeSoto and Gage are trying to rescue the unconscious boy stuck in the tree, Gage drills a hole in the tree, and when he reaches down to the oxygen tank and then places the tube in the hole, the outlines of both the mic transmitter and wire are visible on Gage's shirt.
Visible crew/equipment: When Dixie looks for Sally to flush the patient's eyes, she finds her in the hallway, and there are two actors' tape marks on the floor in the waiting room, where Dixie and Mike, the patient's friend, will stand in a moment.
Visible crew/equipment: When Morton is talking with the fireman's widow, DeSoto tells Morton that Early wants to see him, and when Morton walks through the door DeSoto's foot moves, and we see the actor's black tape mark on the floor by his foot.
Visible crew/equipment: After Brackett tells Jenny that they may have to put Koki down, Dixie walks into Jenny's isolation room, saying that they have the latest lab report, and the actor's tape mark is visible on the floor at Dixie's feet.
Visible crew/equipment: At the nurses' station, Early asks Dixie about Carol, and when Dr. Knott pulls away in the wheelchair to go get Carol, the actor's tape mark on the floor is visible, precisely where Brackett had been standing moments ago.
Visible crew/equipment: When Early walks over to the nurses' station after removing the boy's stuck finger from the steering wheel, the two actors' tape marks are visible on the floor, where Brackett stands and where Early is about to stand.
School Days - S2-E14
Visible crew/equipment: When Roy walks into the kitchen late at night, while Billy's alone on the couch studying about emergency medicine, there are moving shadows on the floor towards the left of the screen.
Peace Pipe - S2-E5
Visible crew/equipment: Just after the drunk driver is loaded onto the ambulance, when Roy tells Johnny about Debbie's pulse and respiration, and that she's in bad shape, then also when Roy tells Captain Stanley to make it quick, a crew member sitting atop a ladder with set lighting beside him are visible in the background.
Visible crew/equipment: During the structure fire, after Roy finds the boy and his dog under the bed, when Roy heads down the stairs and then rushes back up, as he gets to the top of the stairs when the camera pans to the left we can see the barndoor set lighting, at the top left side of the screen.
Visible crew/equipment: After John and Roy rescue the elderly man from the burning house, while Roy gets the man's vitals in the closeups, the large 12-light par bank rig is visible behind Roy at the left of the screen.
Visible crew/equipment: While en route to the structure fire, Mike is driving Engine 51, and seated backwards in the jumpseat behind Mike is Marco, who's wearing a helmet and his turnout, but in the shot from the POV behind Mike, we see the reflection in the rear-view mirror of the grey haired crew member, who is seated facing forward behind Mike.
School Days - S2-E14
Visible crew/equipment: When Squad 51 gets pulled over to help the guy with a snake on his stomach, just as Johnny reaches over to take the broom from Billy, the outline of the lav mic transmitter is visible on the back of Johnny's shirt.
Visible crew/equipment: When Johnny and Roy are speaking with the Battalion Chief in the apparatus bay, about who could have stolen the money, when they walk forward there are two tape marks visible on the floor behind them, where they were just standing.
Visible crew/equipment: While Roy's in the office making out the activity report for the training center, Johnny walks over to Ed who is standing beside the map, and when they're dispatched to the overdose, as they get into the squad we can see two tape marks (one white, one black) on the floor, where Johnny and Ed had been standing.
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.