Ambiguity Reigns

[Olebird]

As it turns out, the fumes from some floor cleaners can trip certain smoke/fire sensors used in automatic halon fire suppression systems typically found in large computer centers and bilges. A similar switch is provided to prevent the accidental release of large volumes of very expensive Halon gas - when one mops the floor or cleans the bilge.

Equally ambiguous in several languages - don't ask me how I know!

 

[AlaskaProf]

Wifey B: Did the can have wheels? If not, would you still consider a can parked?

Sorry, I had a hard time on the for sale and piano part as I was still hung up on the can.

Auto correct.

Van

 

[Greg S]

In a properly put together automatic fire system, that switch is to prevent (override) the system from discharging. It is a normal part of the system. It prevents discharge if work is going on or something small might set it off but doesn't require a discharge of the system. Many electronically controlled systems will have an alarm sound a few seconds before discharge. This gives you enough time to hold the switch, preventing discharge in a false alarm.

 

[rslifkin]

A lot of boat systems I've seen aren't electronically discharged, however. They're usually a mechanical heat trigger with electronics to shut down engines, etc. when the bottle pressure drops.

 

[twistedtree]

Quite interesting replies, since they are diametrically opposed operations, and quite dangerous if mixed up.

I don’t doubt the “disable the automatic system” operation. But my own experience with boats is around the accompanying engine shutdown system, and the need to “override “ to get running again. The whole shutdown concept I think is unique to environments with engines and exhaust fans, unlike data centers.

 

[twistedtree]

Sorry, hit “send” too soon.

The shutdown systems I have seen have a switch on the tank that opens when the tank discharges. That signals the shutdown of engines and fans.

An easy, and important periodic test, is to disconnect the electric plug from the tank switch, being careful not to accidentally fire the tank. All engines and exhaust fans should shut down.

Now activate the mystery “override” switch, and the fans should come back to life and you should be able to restart the engines.

 

[menzies]

Sorry, hit “send” too soon.

The shutdown systems I have seen have a switch on the tank that opens when the tank discharges. That signals the shutdown of engines and fans.

An easy, and important periodic test, is to disconnect the electric plug from the tank switch, being careful not to accidentally fire the tank. All engines and exhaust fans should shut down.

Now activate the mystery “override” switch, and the fans should come back to life and you should be able to restart the engines.

I think I may be not only speaking for myself here, but many others....

I ain't trying that!

 

[Tiger_DFT]

Many many years ago....I had to work in IBM's Sydney, (NSW, Australia) computer room. Getting a pass into that room wasn't easy, even issued with a time expiring(measured in hours) photo id. Once in the room all was well until I read a notice on the Halon fitted Computer room exit door...


EMERGENCY DOOR only....NOT TO BE used under ANY circumstances.



I wondered why it had a door handle??

 

[BruceK]

Many many years ago....I had to work in IBM's Sydney, (NSW, Australia) computer room. Getting a pass into that room wasn't easy, even issued with a time expiring(measured in hours) photo id. Once in the room all was well until I read a notice on the Halon fitted Computer room exit door...


EMERGENCY DOOR only....NOT TO BE used under ANY circumstances.



I wondered why it had a door handle??

Or why there was even a door, if it was "NOT TO BE used under ANY circumstances".
Reminds me of the sign in Ireland: "Do not lean bicycles against this sign".

 

[twistedtree]

I think I may be not only speaking for myself here, but many others....

I ain't trying that!

It sounds scary, I agree. But it really isn't that bad. Take a look at your tank and you will see the manual release cable connected up. That's for the manual release pull knob located somewhere outside the ER. There might also be a temperature triggered release. Don't mess with those.


But there should also be a harness with a couple of wires and a plug connected to a pressure switch on the tank. Pull that plug off, but don't mess with anything else. Removing the plug will simulate a discharged tank.


Or better yet, next time you have the system inspected, have the tech show you to safely test the system, and how to use it properly.


As I think about all this, it's really pretty scary how little we all know about or fire systems, shut down, and how it all works. I know I had no clue when I started out, and only barely a clue until by system went tits up and disabled the entire boat, thankfully at the dock and not underway.

 

[twistedtree]

Many many years ago....I had to work in IBM's Sydney, (NSW, Australia) computer room. Getting a pass into that room wasn't easy, even issued with a time expiring(measured in hours) photo id. Once in the room all was well until I read a notice on the Halon fitted Computer room exit door...


EMERGENCY DOOR only....NOT TO BE used under ANY circumstances.



I wondered why it had a door handle??

That's great. I think I'll paint that on a wall in a room sometime, just for kicks. After all, if it's a door not to be used under any circumstances.... is it really as door? Great philosophers have pondered lesser questions...

 

[angus99]

Ambiguity: not being clear in written or oral communication . . . or something like that.

 

[helm]

We do exactly what Twistedtree says every year. To get to the outboard side of the port engine I have to remove the fire extinguisher tank, which involves also unplugging the two electrical connections at the discharge apparatus. While the extinguisher is out, to start the engines we have to place our switch in the override position at the helm extinguisher display. It’s actually all very simple on our boat but I wasn’t familiar with the system when I purchased our Lindell 36 so I had a marine extinguisher service tech come by who recertified our tank and reviewed the system operation with me as well as proper removal and replacement of the tank.

 

[AlaskaProf]

That's great. I think I'll paint that on a wall in a room sometime, just for kicks. After all, if it's a door not to be used under any circumstances.... is it really as door? Great philosophers have pondered lesser questions...

Schroedinger's Fire Escape

 

[RickyD]

I suspect it overrides the automatic fire shutdown, allowing you to restart the engine(s). Automatic shutdowns typically go hand in hand with an automatic fire extinguishing system in equipment space. When the fire system activates and discharges the suppressant, then engines and fans need to be shut down at the same time, otherwise they draw all the suppressant out of the equipment space rendering it useless.


But then you need to get running again, and that's where an override switch comes into play. It overrides the automatic shutdown, and you can restart.

This is my thought also. My switch looks different but it allows me to start the engines and or genset.

 

[Deano]

I agree it is to restart engines after fire system activation. On activation the the engines shut down so they don’t inhale all the fire suppressant.

 

[garychurch]

Do you have a Fireboy system in the engine room that automatically activates in case of engine room fire? A Fireboy system when activated is designed to close all engine intakes and exhausts closing the engine room to a source of fresh air (i.e., oxygen), expel fire suppressing chemicals and shutdown the engines.

There is a switch generally in the helm area similar to the one shown, that allows the engines to be restarted after they have been shutdown by the activation of the Fireboy system.

 

[rgano]

Do you have a Fireboy system in the engine room that automatically activates in case of engine room fire? A Fireboy system when activated is designed to close all engine intakes and exhausts closing the engine room to a source of fresh air (i.e., oxygen), expel fire suppressing chemicals and shutdown the engines.

There is a switch generally in the helm area similar to the one shown, that allows the engines to be restarted after they have been shutdown by the activation of the Fireboy system.

Back in 1986 I wanted to install a FireBoy automatic Halon release system in my engine room on my 1972 woodie GB, but I did not want to go through the expense and hassle of installing an automatic engine shut down system. Instead, I installed the bottle and wired it to two of their alarms, one at each helm and figured I would be smart enough to shut the engines down if either sounded off. It is a bit of reverse thinking where the engines are automatically shut off by complete systems, but I figured I would be fast enough on the shutdown manual pulls.

My current boat has a SeaFire system which auto shuts down the main and genny. I have never seen an auto closure device on any intake opening on vessels smaller than a ship, but I am sure some higher end yachts than I am sed to dealing with have them.

 

[Comodave]

I used to be an engineer in a large computer data center. We had halon systems in every computer room and each room had a halon abort switch. Management said in case of an alarm it was the engineers job to get someone to hold the abort switch and then go put on a Scott pack and fight the fire. I told them ok, then thought if the alarm goes off my job is to get everyone out of the area and then haul ass myself. If they were to fire me for not fighting the fire, ok. Fortunately the alarm never went off while I worked there.

 

[HopCar]

Real men don’t need no stinking instructions! Flip the damn switch! If you survive let us, know what happened.

 

[markpierce]

No list, nevertheless, for me desiring departure:

Check weather forecast and decide if boating plan needs to be canceled or modified.

Bring aboard and secure desired supplies.

Wash down boat if needed.

Hoist any desired flags.

Flip all switches at the electrical panel for desired systems. Check if systems are operating.

Check any notes left concerning thru-hulls or other matters of concern to be opened or addressed.

Check fuel levels of tanks. Assure adequate fuel supply, particularly the one currently connected. Same for water tanks.

Having previously noting any boat lean, switch fuel tanks when needed.

Disconnect and bring aboard shore electrical line.

Start engine. If no instant start, fuel-prime.

Once engine started, check adequacy of exhaust water flow and engine-gauge readings.

Disconnect and secure dock lines.

Change gears only at minimum RPM, orient boat with bow thruster or other means so exit from berth is "clean."

Check operation of air horn: three shorts backing from berth and/or one prolonged exiting marina.

Bring aboard fenders after leaving berth.

 

[menzies]

No list, nevertheless, for me desiring departure:

Check weather forecast and decide if boating plan needs to be canceled or modified.

Bring aboard and secure desired supplies.

Wash down boat if needed.

Hoist any desired flags.

Flip all switches at the electrical panel for desired systems. Check if systems are operating.

Check any notes left concerning thru-hulls or other matters of concern to be opened or addressed.

Check fuel levels of tanks. Assure adequate fuel supply, particularly the one currently connected. Same for water tanks.

Having previously noting any boat lean, switch fuel tanks when needed.

Disconnect and bring aboard shore electrical line.

Start engine. If no instant start, fuel-prime.

Once engine started, check adequacy of exhaust water flow and engine-gauge readings.

Disconnect and secure dock lines.

Change gears only at minimum RPM, orient boat with bow thruster or other means so exit from berth is "clean."

Check operation of air horn: three shorts backing from berth and/or one prolonged exiting marina.

Bring aboard fenders after leaving berth.

Did you get the right thread?

 

[Olebird]

Checkt list

I think you meant to post in the Check List thread ??


I check oil and coolant levels and drive belts in Engines and Genny at least once a day. FWIW

No list, nevertheless, for me desiring departure:

Check weather forecast and decide if boating plan needs to be canceled or modified.

Bring aboard and secure desired supplies.

Wash down boat if needed.

Hoist any desired flags.

Flip all switches at the electrical panel for desired systems. Check if systems are operating.

Check any notes left concerning thru-hulls or other matters of concern to be opened or addressed.

Check fuel levels of tanks. Assure adequate fuel supply, particularly the one currently connected. Same for water tanks.

Having previously noting any boat lean, switch fuel tanks when needed.

Disconnect and bring aboard shore electrical line.

Start engine. If no instant start, fuel-prime.

Once engine started, check adequacy of exhaust water flow and engine-gauge readings.

Disconnect and secure dock lines.

Change gears only at minimum RPM, orient boat with bow thruster or other means so exit from berth is "clean."

Check operation of air horn: three shorts backing from berth and/or one prolonged exiting marina.

Bring aboard fenders after leaving berth.

 

[Wayne]

In a former life, I was a senior engineer in a Navy-contracted radar development site. All Navy work areas were "protected" by a huge, very complicated Halon system with bottles of Halon in various locations with pipes extending the system to every nook and cranny. Every Navy crew that came through to train on the ship radar system had to train on the Halon system, too. The Navy crews had to test it - supposedly once for each class (as I remember). They were supposed to "safe" the system before running through the tests. Invariably, somewhere along the test the Halon system would go off. It sounded like a freight train crashing through the building.

 

[markpierce]

I think you meant to post in the Check List thread ??

Yes I did.

I check oil and coolant levels and drive belts in Engines and Genny at least once a day. FWIW

My mechanic checked them last week. They are fine. Consider that periodic maintenance.

 

[Jan Wright]

Fire suppresion systems

First question should be..."What type system do you have on board"?
Second, Why don't you know already...
Third, you should have as much information about your ship on a laptop or a portable drive. and continuously to update your files and logs...as you go...

 

[wkearney99]

Now, imagine late at night, all alone doing boring paperwork, when the alarm goes off. Talk about an adrenaline rush!

I found a sound clip that was almost exactly the same as the one used in a college computer lab. That and the breaker for the magnetic releases on the doors. If you've ever seen how elephant seals get around you'd know what it looks like when a couple of server room neckbeard sysadmins hear that sound and see the doors closing. Just HURLED himself out of the chair and into the doorway to prevent it from closing. The folklore surrounding the dangers of Halon in the lab only grew larger after that.

 

[bayview]

You operate that switch before Louie the torch comes to do his work.

 

[bayview]

That switch is for non emergency ER fires