Revealing mistakes: The head nurse who talks with Jack is seen in the glass walking up behind him waiting on her cue as he looks into Chestnut's room.
Continuity: When Jack and Linda are at the bar and the guys make Linda chug her drink, she is about to finish it, but in the next shot her glass is half full.
Anachronisms: Much of the equipment (Big Ed flashlight, style of air-pack mask, etc) carried by Morrison (and other firefighters) in his "early years" as a firefighter was not available until more recent times (mid-'90s)
Continuity: After Jack saves the girl from the fire, another firefighter points out a bleeding wound on his head. When Jack walks into the church later that night, the wound has vanished completely.
Continuity: When the fight breaks out in the firehouse, coffee gets spilled on the table. But in the next shot, the table is spotless.
Continuity: When Jack is lowering the victim from the warehouse in the beginning of the movie the rope is wrapped around the metal construction. However, when the explosion occurs to his side we can see that the rope is no longer wrapped around the metal but simply lying across it.
Continuity: At the beginning of the movie, Jack is carrying a red bag which he puts down when tending to the first found victim. After having the other firefighters carry him down, the bag reappears when he is going after the second victim, but he never picked it back up.
Revealing mistakes: When Jack is on the rope holding the man at the city high-rise fire, you hear a news chopper saying that it is over the fire scene, but after Jack says that he will drop the man if he doesn't calm down, you can see the word "POLICE" on the bottom of the chopper.
Continuity: When the trucks are responding to the fire during the snowstorm there is an overhead shot of the trucks going down the street. In that shot, you can see that Ladder 49 is a more modern Pierce tiller ladder but then it switches back to an older Seagrave tiller ladder.
Continuity: When the large explosion occurs while Jack is in the warehouse, you see the floor cave in under his feet, immediately followed by Jack sliding in. In the next close-up scene, Jack is obviously on the slope struggling to stay on that floor and not fall into the newly created hole. In the next scene, you see the floor is again whole, then caves in, and once more you see Jack start to slide down the angled floor toward the hole.
Errors made by characters (possibly deliberate errors by the filmmakers): When the Priest marries Jack and his bride, he announces to the members of the church "Mr. and Mrs. Morris". It is clear throughout the movie that the last name of the character is Jack Morrison.
Continuity: In the warehouse when the floor caves in and Jack starts falling you can see that one of his legs are on fire. The next scene there isn't the slightest burn mark on his pants.
Continuity: When the engine and ladder truck leave the firehouse on Jack's first working fire, Tommy Drake is driving the ladder truck. However, upon arrival on the scene of the fire, Ray Gauquin is driving the ladder truck.
Continuity: During the bar scene on Jack and Linda's first date, the position of the lime slice and strawberry on Linda's glass changes on both the first and second drink several times throughout the scene.
Incorrectly regarded as goofs: During the wedding scene, Jack and Linda leave the party with children. These are not actually their children, but rather family members' children.
Continuity: When Chief Kennedy is talking to trapped Jack Morrison on the radio from outside the building, during the scenes showing Jack trapped in the burning building, the type of radio Chief Kennedy is using changes multiple times. Sometime Kennedy is talking on a portable radio with no mic attached to it, and sometimes he is talking on a portable radio with a speaker mic attached to it, and is holding the mic in his hand.
Errors made by characters (possibly deliberate errors by the filmmakers): In the warehouse with the second victim, Jack gives him his mask to breathe through. When you pull off your mask, you should push the blue button. If you don't, the tube the air goes trough doesn't lock and all of your air goes away. When you put the mask on, and start to breathe, the tube unlocks itself, so Jack should have locked it again when he took the mask back.