Visible crew/equipment: During the rescue at the construction accident, when the man with the back injury is hanging from his line and is lowered after Roy untangles the block, we can see that in addition to the rope wrapped around the man there's wire and support that go under the man's jumpsuit. The wire/support are gone once he's lying on the balcony and they remove the rope.
Visible crew/equipment: Station 51 responds to a building collapse with the trapped boy, and when they enter the building with Tommy's friend, the actor's white T-mark is visible on the floor.
Visible crew/equipment: At Rampart, when Gage and DeSoto walk into the staff lounge, where Dixie and Dr. Brackett are seated at the table, there is an actor's T-mark on the floor behind Dixie, where DeSoto stands.
Visible crew/equipment: On site at the construction accident with the back injury victim, when Roy climbs over the tower's railing we can see the yellow canvas strap attached through the leather loop of his lifebelt, but when he descends to the injured victim, the yellow canvas strap is now also attached to a carabiner protruding from under his turnout coat, by his pants, which presumably is attached to additional hidden support.
Visible crew/equipment: On site at the construction accident, when the man with the back injury is lying in the stokes and being lowered with the ladder, a crew member/cameraman is visible on the landing at the lower right side of the screen.
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.