Damage control
Posted: Mar 4th, '16, 12:25
I'm posting this because of the other thread about the marina fire... Having been a damage control NCO in a previous life it's a subject that's close to my heart...
And, unfortunately, as far as I can see, most people don't really take the issues seriously...
Damage control on vessels takes two major forms:
The first form being fire, possibly the most scary thing on a boat... The USCG regulations for a boat my size (46') are totally inadequate!... The regulations require 3 extinguishers (2 if there's a builtin engine room extinguishing system)... While the regulations specify the type (USCG approved) their size is left up basically to the owner/market... The most common fire extinguishers I see are the 2.2 pound units... West Marine only carries 2 pound chemical (powder) extinguishers... BOW (Boat Owner's Warehouse) also only carries chemical (powder) extinguishers though they offer several sizes (2-3 pounds)... These might be adequate for a small boat but they're (IMHO) completely inadequate for medium and bigger sized boats...
In addition, there's the issue of the fire fighting agent in the extinguishers... Just about EVERY boat I see has extinguishers with a chemical (powder) fire fighting agent... While powder is reasonably effective it's corrosive and creates a huge mess!... I put this mostly down to ignorance and, to some degree, penny pinching by the owners... The alternative used to be Freon 1301... Unfortunately that agent has been taken off the market (bad for the environment - contributed to the hole in the Ozone layer)... The more environmentally friendly alternative is Freon 1211 (a.k.a. Halon)... It's almost as effective...
At this point it's important to explain how Freon/Halon works... Basically the gas is attracted to the heat of the fire, once there it bonds chemically with the oxygen and thereby smothers the fire...
Advantages:
And I'm very happy with being somewhat paranoid on this issue... Following some engine work (tune up, air cooler cleaning, replacement of a turbo with a cracked housing) we went out on a sea trial last Saturday... On the way back, practically at the entrance to the marina, my son comes up to the flybridge and tells me there's smoke coming out of the engine room... As I got ready to open the engine room hatch I heard the FireBoy discharge so I decided to wait a few minutes with opening the hatch... As the Halon also shut down the engines I concentrated on heaving some lines to some people on the nearest dock to be pulled in so as to tie up...
After the smoke cleared I investigated what happened... The turbos on my 8V92TI DD's are so called "dry" turbos... They're cooled by the oil that flows through them... One of the oil return lines (metal pipe) cracked... Oil was flowing onto the heat blanket on the exhaust line going to the turbo... Due to the FireBoy the damage was pretty limited... The underside of the 3 hatches closest to the turbo (starboard side turbo of port engine) were scorched, some hoses close to the turbo were also scorched and there was smoke damage all over the engine room... Except for my boat having been properly equipped this could VERY easily have been a total loss!!!
The second form is water ingress... The hull integrity can be breached in various ways... Mechanical (e.g. hitting something hard), chemical (e.g. corrosion causing the breaking of a through hull)... With the exception of the very small number of boats that have so called crash valves installed all boats I have seen are only equipped with pumps capable of dewatering so called nuisance water (minor leaks, condensation etc) and absolutely nothing that can be considered an emergency dewatering pump...
Originally my boat had 2 x 32 volt centrifugal bilge pumps of 1,500 gallon/hour (one in the cockpit and one under the owner's cabin)... I replaced all of them with new 1,750 gallon/hour units and I doubled them up... So now I have 4 of these... In addition, I have installed 2 additional 4,000 gallon/hour 12 volt units... So, where I once had a single pump (supplied by a single source of power) of 2,000 gallon/hour in any given location I now have 3 pumps with a total capacity of 7,500 gallon/hour... Sourced from two independent power sources...
The engine room used to have 2 x 32 volt diaphragm pumps with a combined capacity of 200-300 (estimated) gallon/hour... As I have been unable to find suitable 32 volt pumps they have been replaced with 2 x 12 volt diaphragm pumps with a combined capacity of 500 gallon/hour... In addition, I have installed 2 32 volt centrifugal pumps with a combined capacity of 3,500 gallon/hour... In addition, I have a couple of 1 HP 110 volt submersible pumps... And a small mobile gas generator to run them if the main power is out... Crash valves are on the "to do" list...
Am I paranoid?!... Probably I am somewhat paranoid on the issue... However, it has already saved my ass once so I'm not going to seek treatment... After all, the fact that one is paranoid doesn't mean there isn't somebody (Mr. Murphy) out there who is out to get me...
And, unfortunately, as far as I can see, most people don't really take the issues seriously...
Damage control on vessels takes two major forms:
The first form being fire, possibly the most scary thing on a boat... The USCG regulations for a boat my size (46') are totally inadequate!... The regulations require 3 extinguishers (2 if there's a builtin engine room extinguishing system)... While the regulations specify the type (USCG approved) their size is left up basically to the owner/market... The most common fire extinguishers I see are the 2.2 pound units... West Marine only carries 2 pound chemical (powder) extinguishers... BOW (Boat Owner's Warehouse) also only carries chemical (powder) extinguishers though they offer several sizes (2-3 pounds)... These might be adequate for a small boat but they're (IMHO) completely inadequate for medium and bigger sized boats...
In addition, there's the issue of the fire fighting agent in the extinguishers... Just about EVERY boat I see has extinguishers with a chemical (powder) fire fighting agent... While powder is reasonably effective it's corrosive and creates a huge mess!... I put this mostly down to ignorance and, to some degree, penny pinching by the owners... The alternative used to be Freon 1301... Unfortunately that agent has been taken off the market (bad for the environment - contributed to the hole in the Ozone layer)... The more environmentally friendly alternative is Freon 1211 (a.k.a. Halon)... It's almost as effective...
At this point it's important to explain how Freon/Halon works... Basically the gas is attracted to the heat of the fire, once there it bonds chemically with the oxygen and thereby smothers the fire...
Advantages:
- First and foremost effectiveness!... Discharge Freon/Halon at around 5% by volume in the compartment and all fire will be extinguished... Which is why this agent is used pretty much exclusively on airplanes...
- Closely followed by the fact the fact that Freon/Halon is not toxic to the human body (unlike, for example, CO2)... Which is why it's used almost exclusively on airplanes...
- Closely followed by the fact that Freon/Halon is a so called "clean agent"... There's absolutely no cleanup following a discharge... Which is why it's used almost exclusively on airplanes and very commonly in IT installations (phone exchanges, server rooms etc)...
- Cost... A Freon/Halon extinguisher will cost roughly double the cost of a chemical (powder) extinguisher...
- Not as effective in open environments...
And I'm very happy with being somewhat paranoid on this issue... Following some engine work (tune up, air cooler cleaning, replacement of a turbo with a cracked housing) we went out on a sea trial last Saturday... On the way back, practically at the entrance to the marina, my son comes up to the flybridge and tells me there's smoke coming out of the engine room... As I got ready to open the engine room hatch I heard the FireBoy discharge so I decided to wait a few minutes with opening the hatch... As the Halon also shut down the engines I concentrated on heaving some lines to some people on the nearest dock to be pulled in so as to tie up...
After the smoke cleared I investigated what happened... The turbos on my 8V92TI DD's are so called "dry" turbos... They're cooled by the oil that flows through them... One of the oil return lines (metal pipe) cracked... Oil was flowing onto the heat blanket on the exhaust line going to the turbo... Due to the FireBoy the damage was pretty limited... The underside of the 3 hatches closest to the turbo (starboard side turbo of port engine) were scorched, some hoses close to the turbo were also scorched and there was smoke damage all over the engine room... Except for my boat having been properly equipped this could VERY easily have been a total loss!!!
The second form is water ingress... The hull integrity can be breached in various ways... Mechanical (e.g. hitting something hard), chemical (e.g. corrosion causing the breaking of a through hull)... With the exception of the very small number of boats that have so called crash valves installed all boats I have seen are only equipped with pumps capable of dewatering so called nuisance water (minor leaks, condensation etc) and absolutely nothing that can be considered an emergency dewatering pump...
Originally my boat had 2 x 32 volt centrifugal bilge pumps of 1,500 gallon/hour (one in the cockpit and one under the owner's cabin)... I replaced all of them with new 1,750 gallon/hour units and I doubled them up... So now I have 4 of these... In addition, I have installed 2 additional 4,000 gallon/hour 12 volt units... So, where I once had a single pump (supplied by a single source of power) of 2,000 gallon/hour in any given location I now have 3 pumps with a total capacity of 7,500 gallon/hour... Sourced from two independent power sources...
The engine room used to have 2 x 32 volt diaphragm pumps with a combined capacity of 200-300 (estimated) gallon/hour... As I have been unable to find suitable 32 volt pumps they have been replaced with 2 x 12 volt diaphragm pumps with a combined capacity of 500 gallon/hour... In addition, I have installed 2 32 volt centrifugal pumps with a combined capacity of 3,500 gallon/hour... In addition, I have a couple of 1 HP 110 volt submersible pumps... And a small mobile gas generator to run them if the main power is out... Crash valves are on the "to do" list...
Am I paranoid?!... Probably I am somewhat paranoid on the issue... However, it has already saved my ass once so I'm not going to seek treatment... After all, the fact that one is paranoid doesn't mean there isn't somebody (Mr. Murphy) out there who is out to get me...