Unlike Some Other Movies, Saboteur (1942) Gets Fire Sprinkler Systems Right

Hello, reader. Jeremy here, and boy am I excited about today's newsletter. This one comes from my longtime pal Joey Brown, an all-around great human being and a fellow bass player that I shared a stage with many times in our teenage years. (His band was a lot better than mine. Also, shouts out to Cave 9.) Joey hit me up not too long ago and asked if he could write a piece about the (in)accuracies of fire sprinkler systems in cinema and, as I told him, that is exactly the sort of thing we like to do here at Dust On The VCR. And he picked a pretty great Hitchcock film to focus on too. Take it away, Joey!

Today I’d like to talk about fire safety. Specifically, how sprinkler systems are portrayed in movies.

In my normal 9-5, I work as a fire prevention technician, which is a fancy title for Sprinkler Dude. Basically, I inspect and maintain fire sprinkler systems. I don’t know if you’re like me, but when I see my job portrayed on screen, I often find myself going “Lol, that’s not right.” This has been a common reaction for me when a movie incorporates sprinkler systems into the plot.

So imagine my surprise while watching Alfred Hitchcock’s Saboteur and suddenly…there’s a sprinkler system accurately portrayed! But before I get ahead of myself, it’s worth pointing out some examples of movies that get this stuff wrong. 

The most common misconception about sprinklers is that when a fire appears under one sprinkler head, all sprinkler heads in an area go off at the same time. This would simply never happen. When Hilary Duff holds a match to a sprinkler head in The Perfect Man, several others go off as well—even sprinklers in other rooms! In reality, if you hold a flame to one sprinkler head, only that one sprinkler will go off. Consequently, if there’s a large fire in a room with four sprinkler heads, only those four will go off. Not the ones in the hallway. Not the ones in the other room. Just the ones touched by flames. Once those sprinkler heads pop, it triggers a flow of water, which then triggers an alarm. 

Speaking of alarms, let’s talk about another common misconception: pull stations. Pull stations are the little red boxes that you see hanging on walls. They have a small handle and usually say something like “Pull for Alarm.” These actually have nothing to do with sprinklers. Activating a pull station will only trigger an alarm. You won’t get any water anywhere. So next time you watch Diana Ross yank a pull station in The Wiz or Tim Meadows smash one with a bat in Mean Girls, you’ll know it’s not accurate for all those sprinkler heads to go off. None will go off at all!¹

One more common misconception: smoke. Films like Major League and The SpongeBob SquarePants Movie will lead you to believe that smoke will set off a sprinkler head. This is also false. Sprinkler systems are pressure-based. Each head has a bulb or a metal link that holds water from releasing. The bulb has to pop or the link has to break in order for water to flow, and it takes a minimum of 155 degrees for that to happen, which means that actual flames have to be close to the head in order to release the water.²

This brings me to another point. In movies like White Men Can’t Jump and Just One of the Guys, you’ll see an extreme closeup shot of a sprinkler head without a link or a bulb.³ Then water will all of a sudden start shooting out of it. C’mon, man. You gotta have a bulb or a link in there to be accurate!

It’s about plausibility, really. You just have to consider the situation and decide if it works within the rules of the movie or if it would work in that particular reality. For example, in Bruce Almighty, Bruce sets off all the sprinklers in a room at once, which would never happen in reality. But he has the power of God, of course, so it’s fine. In Blade, a bunch of vampires are dancing in a club when blood comes through all of the open sprinkler heads at the same time. Reader, I know how this sounds, but with the right customized equipment, it’s plausible.

Now that you know how sprinkler systems are supposed to work, let’s get to the accuracies of Saboteur.

In this film, a man named Barry has been framed for setting fire to his workplace, which happened to accidentally kill his best friend. Insisting he’s innocent, he races from place to place, eluding capture from the authorities.

Eventually, he is captured by the people who framed him, and what do they do? They lock him in a pantry with one lone upright linked sprinkler head. In a moment of ingenuity while lighting a cigarette, he notices the head and proceeds to light a match, partially melting the link. He then knocks it out quickly, which triggers immediate water flow.⁴ He even throws a sack over it so he won’t get wet! The flow of water sets off the alarm, which alerts someone nearby to his location and allows him to escape.⁵ There are several shots of other rooms and hallways, and wouldn’t you know it, the sprinkler head in the pantry appears to be the only one that went off.

I was so happy when I saw this. Not only does this film feature a thrilling scene atop a bridge and another one atop a famous American landmark, it accurately portrays how sprinkler systems are supposed to work! Which, to me, was also thrilling.

Reader, I hope you learned something today. And remember: You won’t get wet if you pull a pull station. (I’m looking at you, Mel Gibson in Lethal Weapon 4.)⁶

1. Don’t get me wrong. If you see a fire or smoke, pull that bad boy! That’s what they’re there for! And if you see water spraying from a sprinkler head, the alarm is already handled. Just get out of there!

2. A bulb is a glass tube with a small bubble in it. Once the bubble heats up to the heads rated temperature, it pops and releases the water. Likewise, a link is two pieces of metal held together with a smaller piece of metal that melts when heated. Once the small piece of metal melts, the other two pieces fall away and release the water. Got it? Good.

3. In Just One of the Guys, the actor sticks rolled-up toilet paper through an open sprinkler head then sets the toilet paper on fire. There’s no bulb to pop! Why start a fire?

4. Knocking the link out wasn’t necessary, but he was trying to escape. I would be trying to knock that bad boy out as fast as I could too!

5. We don’t actually see him escape, but this is the logical explanation.

6. If you want to see more than 130 scenes from movies and TV shows featuring faulty fire sprinklers, check out the YouTube channel Films on Fire – Sprinkler Sense.