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Shipboard safety and security

Many firefighting chemicals are actually quite reactive... just not reactive in a way that results in maintaining fires.

IIRC what I learnt about firefighting, from the current firefighting products only Halon and CO2 snow can safely be used if delcate electronic equpment without damaging it.

Of course, in the future, as tech advances, there might be other usable products...
 
The last thing you want to do is use dry chemicals on electronics... if you want to save them. PKP and other dry chemicals are highly corrosive to electronics and they are a nightmare to clean up afterwards. But, if the point of ignition can be eliminated, dry chemicals work incredibly well on large fires. Their only weakness is you have to eliminate any point of ignition to prevent it reflashing immediately.
Ships often have a dual system in engine rooms for firefighting now. They use a combination of foam and dry chemical. Works gangbusters. One person can put out a huge fire in minutes or less using one of these... assuming they don't panic...
 
Fire triangle: a fire needs fuel, oxygen, and I think it was heat. First step in fire safety is prevention: eliminate fuel sources and ignition sources. Your walls, flooring, furnishings and so forth are rated as nonflammable, or at least nonflammable within the circumstances they're likely to encounter. (Some materials are nonflammable only up to a certain temperature, and you may have limited choice about using them. Furniture is often in this category. They'll hold out against matches and burning paper, but once the compartment hits, say, a thousand degrees, they're just another fuel source.) Your kitchen is regularly cleaned and policed against accumulation of flammable grease on walls and surfaces. Your detection and automated response systems are tested. Your maintenance schedule includes checks for warm spots that might suggest overheating wiring, and machinery is maintained according to the maintenance schedule to minimize risk of fire due to worn out equipment. Stuff like that

Second is speed of reaction: hit it fast before it grows, and do everything possible to slow its spread and buy you time to defeat it. Sprinkler systems in passenger compartments (with watertight compartments and a drain system, of course), automated halon or CO2 systems in the electrical spaces and the kitchen and areas where water would damage equipment or spread the fire, doors and hatches that close automatically to restrict the fire, (even stateroom doors should have this function), vent systems that automatically seal the affected compartment, clearly marked and easily accessible fire extinguishers, alarm systems that provide information to crew about the location of triggered alarms, safety blankets in clearly marked and easily accessible locations, these are basic.

Third is training. A passenger compartment fire drill should be a mandated requirement the first day out so passengers know what to expect and can gain confidence in the crew. Drills should be called regularly for other compartments to test response to, say, an electrical fire in a server room or main electrical panel, or a fire in the bridge controls or engine room. Does the crew know how to respond if a fire takes down bridge controls? What if there's fire in a cargo container in the middle of the cargo bay, surrounded by other cargo containers? Can they handle unexpected situations?

Of course, fire is not the only danger. There should be regular safety drills against gradual decompression events, CO2 buildup, O2 depletion, just about anything you depend on to survive that might fail in mid-flight, as well as automated systems to trigger alarms and address the problem, and safety and response equipment in secure and easily identified locations. When the pressure alarm goes off and the cabin pressure is gradually falling, you need to be able to find that smoke discharger so you can locate that leak.
 
It's a tetrahedron now...

firetri3.gif


As for training... I can see this being taken only as seriously as the officers on the ship want it to be. That means on civilian (eg., merchant) vessels, it's mostly a hassle that is performed half-@$$ed, if at all, and the officer(s) in charge just pencil whip the paperwork to make it look good. On a military vessel its taken more seriously and somebody's checking. But, even then it can vary depending on the quality of the crew.
 
I design my ships with Airlocks for every major compartment.

I fancy myself as designing my boats with damage control in mind. I'd love to hear everything you do to implement damage control on your boats.
 
Lots of good fire suppression info. What about other hazards?

Apart from the "space" hazards -- fire on board, hull breaches, etc. -- I suggest that most of the shipboard hazards in Traveller are mundane. A merchant ship at TL 11 is just another industrial environment. Hardhats and safety boots in the cargo hold, gents!

Just what are the routine, everyday hazards of working around fusion plants, jump drives, maneuver drives, grav plates, and the like?

If all that heat from the powerplant is released via BFRs mounted astern (Big Effing Radiators), is it safe to be anywhere near the back end of a starship when the power plant is running?

Are grav plates like light bulbs? That is, does their magical grav power fall away with distance, as light does following an inverse square rule? If so, is there a safety threshold for getting real close to an active plate? (If not, why isn't your ship surrounded by whirling, orbiting junk?)

Do magical maneuver drive thrusters get hot? (IMTU they do....)

I assume that (contrary to what the books say) inertial dampers are imperfect. There's always some jolts and bumps. That's what the handrails in the corridors are for.

By the way, all those deckplans with hatches in the floor, opened by a wheel in the middle? Trip hazard. Heck of a problem solver:

Player: "I want to defrobnicate the whatsitometer and magically solve your complex puzzle."

Ref: "It doesn't work like that."

Player: "Canonically, it does ... check in Book--"

Ref: "You trip over the hatch wheel and die."
 
discharging a high volume of chemicals or gasses or foams into limited volume compartments is going to cause serious issues all by itself.

Just the basic complexity of the ship's systems would have wiring and piping running everywhere.

Ventilation (heating, cooling, and air supply)
Electrical (wiring, fiber optics, and anything else to be invented)
Control systems and sensors
Hydraulic systems
Pneumatic systems
Septic sewage
Water supply (hot, cold, and for other uses)
Other gasses (to pressurize systems, or supply these for special needs)
Fuel
Lubrication (of machinery may be done using a centralized system)

some of this seems addressable.

airtight integrity checks at annual maintenance.
electrical connection panels at bulkheads - airtight, connections on both sides
hydraulic/pneumatic systems - no. no high-pressure systems in limited environments, those are a disaster waiting to happen fire or no fire. any such systems would have to be limited to one compartment and localized to machinery of concern and be self-contained to vent overboard on any rupture.
septic sewage - that's what the cabin life support units handle.
fuel - should have discharge piping to engineering and piping nowhere else. a hydrogen leak into an inhabited compartment would be worse than a fire.
lubrication - limited to engineering and localized to machinery of concern.
 
But hydrogen does love to leak....

true, and there is some question as to how a hydrogen-fueled system could work. but we just shrug our shoulders and say "hey, it's the future", and leave it at that. physical damage and its consequences, on the other hand, ought not be ignored.
 
Speaking of fires on space ships, Jan 27, 3 days from now, is the 50th anniversary of the Apollo 1 fire.

And, I reminisce to watching both "The Right Stuff" and "From the Earth to the Moon".

Near the end of TRS, Grissom is being grilled about the hatch on his capsule blowing early during splashdown, causing the flooding and loss of the capsule. Grissom attested that the hatch "just blew", something went wrong and the explosive bolts spontaneously blew the door. But, then you had the examiners talking about how they had been using explosive bolts for years, they'd burned them, crashed them, and all sort of other extreme tests and real world examples, and that they had never "just blown".

The movie leaves with that, leading you, the viewer, to think that Grissom was in fact in the wrong, and that he was responsible for blowing the hatch somehow.

Later, in FtEtTM, a character was talking about that exact same episode with Mercury and that, after analysis, it was ascertained that the bolts did "just blow", exonerating Grissom. However, because of the fact that they could "just blow", the hatch on the Apollo 1 capsule did not have explosive bolts. If it did, there's a chance the crew could have survived the fire.

As the character in the show said "I'm not much of a fan of irony", referring to the common thread that was Gus Grissom. Had his hatch not blown on Mercury, he may have survived the fire on Apollo 1.
 
On general damage control and such. Warships would have more of this than merchant ships, cost being far less of an issue with the former. Besides, merchant ships generally aren't going to be designed for combat.

Some things I'd suggest as design features:

All redundant systems are duplicated such that they run on opposite sides of the ship. That is, the normal feed is on one side, the alternate is on the other.

The fuel tanks would have to be something like thermos bottles and I'd surround those with a separate compartment (it wouldn't have to be very wide) that is either normally in vacuum or was filled with an inert gas like argon or nitrogen. That makes it harder for one to leak such that it does into a space that makes a risk of fire very low.

Venting fuel overboard would be possible to do. Shifting fuel out of one tank to another would also be doable.

There'd be lots of fuel tanks rather than one or a few large one(s).

All bulkhead penetrations would be airtight going through well designed stuffing tubes that would minimize the risk of fire getting through that way and prevent loss of atmosphere between compartments. Something like this:

fig30-2.jpg


These would be a standard part you could order so some variant would be used on any ship by any constructor.

Not all walls or floors on a ship are bulkheads or decks. Some are partitions (thin walls not intended to stop fire or loss of atmosphere) and platforms. These have doors not hatches.

Use of finishes and materials that are fireproof would be common.

There is emergency lighting and you have to change the batteries or it doesn't work when you need it. It doesn't magically work when the power goes away because you still need something to power it.

Water and waste disposal are normally centralized systems because it saves a lot of space and weight over having it decentralized. It also means you can recycle the water and whatnot easier. In other words, the ship has one or more septic (called CHT on ships) tanks for sewage. You just fire the contents overboard somewhere convenient in space and hope it doesn't turn into a "blue asteroid..." :rolleyes:

Hydraulic systems are fine. The fluid would be something non-flammable. They work well for giving a lot of umpf in a compact system.
Pneumatics would be similar. You use an inert gas if the system is closed loop.
For example, rotating all those turrets is best done with a local hydraulic system as you can get anything from very high rates of rotation to very fine slow ones and these are very smooth. You could also have one system driving multiple turrets at the same time.

The fuel processing plant(s) need to be isolated spaces due to what you're doing in them. Placing these in an engine room or elsewhere with other "stuff" only increases the danger during making fuel.

On hatches, most are not automatic on my ships. You have to manually operate them. Having the sort you see in sci fi movies all the time would be a maintenance nightmare. The tracks for the sliding sort would get stuff in them. You have to find room in partitions and bulkheads for them to move into. Instead, they're simply operated with a hand wheel most of the time.

Something more like this:

7.jpg


The sort of iris valve ones would be another maintenance nightmare. Could you imagine trying to keep all the surfaces clean and nice and smooth over say 20 years? Plus they have the slide into the bulkhead issue to contend with.
Instead, the hatch operates like a door and the dogs to seal it are contained inside a panel on the door. If it's automatic you have the motor and such in the door panel and just wiring from it to the ship. The seal around the door and the bulkhead knife edge are easy to clean and maintain.
Yes, you have to step over the hatch combing...

For those inane hand wheel sort of deck hatches you could use something like this:

images_full_67.jpg


That T-wrench would be nearby... At least until it magically disappears and needs replacement right when you need it to operate the hatch...



On engine rooms... IMTU these are noisy, hot, and filled with stuff that you shouldn't brush up against. There's very little open space in them (the antithesis of Star Trek engine rooms). Why waste space in them that could be applied to other things like more cargo?
 
Don't forget the LBB2 Main and Engineering part of the hulls, with a double bulkhead in-between them on some of the GDW plans. Definitely a safety feature- or conversely, a barrier to breaking in or out of each section.

A cheap P-suit in every stateroom, another per crew/passenger in common areas, and another set on board any small craft.

Automated beacons, both on the ship and portable to eject, with big autoinflating here I am radar/light reflection balloons.

A heavy rad suit, 1 per 100 tons of ship, for both EVA and work in an irradiated engineering section.

Emergency battery/light fission reactors, light em up once, for survival and fusion reactor restart.

Hydrogen gas detectors, because hydrogen is one thing, hydrogen and oxygen is another level of problem entirely.

Crash seats on the wall to strap into ala Expanse on the Martian ships.

One helluva grounding system, don't forget a really big 1000 EP drive or spinal weapon is packing 250 GW in it's power feed.

If the artificial grav is off/doesn't exist/damaged, objects are going to be flying around with every vector change, potentially incoming at high speeds, a lot of magnetics/tiedowns/clamps/static mounts will be in order.
 
Instead, they're simply operated with a hand wheel most of the time.

love that hatch. and that wheel, on a deck, certainly eliminates the tripping hazard. nix on the t-handle, you don't want to be scrabbling around in the dark when injured looking for the part that bounced off the bulkhead after a missile hit, you just want to turn it and open it.

correct about the manual doors, but you'll want some kind of iris/automatic/something doors for automatic compartment isolation though. plus there's space issues, a hatch opening into a 1/2 dton airlock is cramping.

heh. love those ct deckplans showing a single powered iris valve between inhabited space and the exterior ....
 
Lots of good fire suppression info. What about other hazards? ...

Well, there's disease control. There are some obvious checks, and far future is likely to have some interesting rapid tests to administer to boarding passengers on the line of some of the tests we're coming up with now.

https://www.quidel.com/immunoassays/rapid-influenza-tests/quickvue-influenza-test

Still, there are likely to be surprises. You could leave port from some outback world with everyone fine and arrive at your destination with half the passengers in fever from something for which they don't have a quick-test. You'd need isolation protocols for anyone who showed signs of illness while en route, confine them to their stateroom and arrange for meals to be delivered and such. Depending on what symptoms are showing (respiratory infections are more likely to transmit than some intestinal bug) you might need to keep scrubs, gloves, masks, paper booties and such in supply so your medic can serve them with less chance of exposure, have a changing station outside the door - basically a cart loaded with the scrubs and stuff for the staff to change when they go in, a red biohazard bag to accept the scrubs and stuff when they exit and take it all off. Perhaps have a set of broad-spectrum antibiotics to administer prophylactically to everyone if someone shows signs of illness. You might well find your ship quarantined until whatever it is runs its course - rarely more than an inconvenience, the captain will be fretting over lost money as his schedule goes awry, but sometimes it could become more serious.

I'd design a ship to put the medic and steward's quarters in with the passengers, limit their contact with the other crew, the other crew quartered in another compartment, separate air vent systems, limit the captain's contact with the passengers to minimize his exposure, have no contact between the other crew and the passengers. May not stop everything, but it should keep your engine room staff at the controls until you can get there.
 
l... you don't want to be scrabbling around in the dark when injured ...

Why are you in the dark? Where is your emergency lighting? Battery powered emergency lights should be standard above exits, and I'd put LEDs at the junction of wall and floor so people crawling under smoke have light to escape by. Maybe even have them as little lit-up arrows pointing to the nearest exit.
 
Sure, those too.

I've mentioned generic suit fitting issues, suit time might show not enough children sized or supertall suits available, and vacuum time is not the time to play the loser to musical missing vacc suit.

Passengers may or may not have experience with donning vacc suits. Fred and Martha Farmer on their honeymoon might not be as able as the seasoned business traveler.

Random useful info: a nice piece on decompression which, farther down after a bunch of math and explanations, includes a useful table on how long it takes to decompress a room:

http://www.spaceacademy.net.au/flight/emg/spcdp.htm

Boils down to:
A 30 m^3 cabin at STP with a 1 sq. mm hole to vacuum drops to 50% pressure in 50,000 seconds (~14 hr.), 5000 seconds (~1hr. 23 m.) from a 10 sq. mm hole, 500 seconds (8 m. 20 s.) from a 100 sq. mm (1 cm x 1 cm) hole, 50 seconds from a 1000 sq. mm (~3.16 cm x 3.16 cm) hole, 5 seconds from a 10,000 sq. mm (10 cm x 10 cm) hole.

A 30 m^3 cabin at STP with a 1 sq. mm hole to vacuum drops to vacuum in ~320,000 seconds (~88 hr. 53m.), ~32,000 seconds (~8 hr. 53 m.) from a 10 sq. mm hole, ~3200 seconds (53 m. 20 s.) from a 100 sq. mm (1 cm x 1 cm) hole, 320 seconds (5m. 20s.) from a 1000 sq. mm (~3.16 cm x 3.16 cm) hole, 32 seconds from a 10,000 sq. mm (10 cm x 10 cm) hole.

Increasing cabin size by a factor of 10 increases the time it takes by a factor of 10. So, a roughly 2 dT space with a 1000 sq. mm hole takes 45 seconds to drop to 50% pressure, while a 20dT space takes 450 seconds.
 
Having each compartment vented over the side, so to speak, is unrealistic particularly on larger ships. There could be hundreds, even thousands, of compartments on a large vessel. Having a system of piping that can vent any single compartment to space would be a very complex one that had the very real risk of a valve failing and some compartment venting when you didn't want it too. Just keeping the system from leaking would be a challenge. Such a system would be an unnecessary nightmare.
For example, you receive damage in one part of the ship or a fire in one compartment. The piping for other compartments runs through that one and somehow gets punctured. Now you have compartments venting to space that shouldn't be. Making repairs afterwards would be complicated by this system too.

Given the already necessary mass of wiring and piping that a ship would have to have, adding more that goes unused 99.8% of the time seems nothing but a waste. The same can be said for a ship-wide automatic fire suppression system. While sprinklers are relatively cheap and reliable, you don't have a water source on a starship that you can use to run such a system. Again, the possibility of a fire in most compartments is so low that you can discount it. The most important and ones that have high risk might have a suppression system fitted. That would be a cost effective trade off.

I'd also think that it'd be easier and better in combat for a spaceship to just seal up all the compartments and bulkheads leaving the atmosphere in place but not being refreshed or connected to other compartments as trying to remove all the "air" and store it somewhere would take considerable time to accomplish and would require considerable storage volume somewhere. The alternative would be to vent "over the side" and then have the problem of replacing the entire ship's atmosphere later.

No it's like your fire sprinkler system one big pipe branching to cover a set number of compartments you may have all the valves in a large compartment open if one of them opens, small compartments may get a single vent valve.
 
Why are you in the dark? Where is your emergency lighting? Battery powered emergency lights should be standard above exits, and I'd put LEDs at the junction of wall and floor so people crawling under smoke have light to escape by. Maybe even have them as little lit-up arrows pointing to the nearest exit.

If the gravity is off, the smoke does not rise. You get moving flame fronts in a sphere with the combustion products inside the sphere.
 
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