Wednesday, September 3, 2014

COMPARTMENTALIZATION AS A DISASTER PREVENTION PLANNING CONCEPT

  NAMAZU THE EARTH SHAKER

 LESSONS FROM NAVAL ARCHITECTURE USEFUL IN  DISASTER RECOVERY PLANNING: 

COMPARTMENTALIZATION (PART 1)

NAMAZU THE EARTH SHAKER, 3,0000 YEAR OLD GIANT JAPANESE DEMIGOD AND AMERICAN ADMIRALTY BOOKS COASTAL ENVIRONMENTAL ANALYST

EDITOR's NOTE: The height of hurricane season is here. Even if the cooler Atlantic surface temperatures grant the U.S. East and Gulf Coasts a reprieve this season, even if there is no major rise in sea level by the end of this century, we have dense coastal settlements in low places. A concept borrowed from naval architecture called compartmentalization if implemented steadily in the coming years could prevent much damage in low lying coastal communities. We published this once before in a more active hurricane season. We see no efforts in this direction, so the observations and suggestions are worth repeating. If we continue to have a quiet season this is an opportunity to start building compartmenting structures.

 Living at the bottom of the Sea of Japan these last 3,000 years has provided me with a unique perspective on Naval Architecture. Ships have been falling from what the normal catfish perspective would call the "sky" since day one. Being of a size that has earned me the nickname "Earth Shaker" my living room is pretty big by human standards. So a lot of these ships literally land on my living room floor. I've taken a lot of interest in them over the years. Over hundreds of years in the early days I could see changes in the designs. There was a gradual reduction in the number of rowing stations and changes in sail plans. Over time, literally thousands of years, the rowing stations disappeared, and with them those awful dead two leggers chained by their ankles to their rowing stations. About one hundred and fifty years ago I began to notice a quantum leap in human ship building technology.


File:Compartments and watertight subdivision of a ship's hull (Seaman's Pocket-Book, 1943).jpg
In this drawing from a 1943 Royal Navy manual you can see the main idea behind compartmentalization which is to divide the hull into segments that can't pass water from one to the other . In this illustration we see basic watertight bulkheads with no close-able openings, indeed no openings at all. . Within these watertight bulkheads there may be many compartments of use to the ship's crew that can become watertight when the limited and special doors, hatches and ports are closed. These openings are sealed when the ship's officers  determine that certain threat levels are relevant to the ship. In heightened but not immediate threat levels many of these compartments are sealed off but many important to normal ship operations and crew health and convenience are left open. These are of such a number that on order the maximum state of watertight integrity can be reached almost immediately by sealing the remaining openings.  

 For thousands of years the ships falling on my living room floor were made of wood. Then iron and steel ships began to appear. Sails disappeared and engines appeared. Of course as a force of nature personified (really a term I prefer to "demigod" but the AAB management seems to think "demigod" has more impact, and my pleas have been ignored. So much for being a "demigod"), I understand the laws of buoyancy. Once humans switched their ship building material from wood which is positively buoyant (it floats) to steel which is negatively buoyant (it sinks) I knew a big change was going to come to hull design. Sure enough, after the first few steel wrecks appeared on the living room floor, I began to notice the appearance of watertight bulkheads subdividing the hulls.These are sort of waterproof walls subdividing the ship's hull into small watertight compartments. In an accident , if enough of these watertight bulkheads hold flooding is contained and ships don't sink. When enough watertight bulkheads are breached, like in the long scraping hole put along much of the hull length in the Titanic, this defensive anti flooding system fails, the hull fills with water, and goes to the bottom of the sea, to the surprise and annoyance of the catfish. We call this defensive anti flooding system "Compartmentalization". Despite the famous exceptions like Titanic it has worked well for ships, and the concept can be applied to other feats of human engineering.


File:Parts of a water-tight compartment (Seaman's Pocket-Book, 1943).jpg
Not all watertight compartments are watertight under any and all circumstances. In the illustration above from a 1943 Royal Navy Manual the watertight compartment is breached by a vertical door, a horizontal hatch, and a port hole. However the hatch cover, door and port hole are capable of watertight seals. Notice that the port not only has a removable glass cover but also a steel cover. The real weak point on all of the openings is the rubber gaskets in each. If the gaskets are not maintained, all of the fittings when closed will result in slow leaks. Most ships have at least three water tight bulkheads that have no openings at all. Battle damage or a collision could breach even these lines of defense. Compartmentalization isn't perfect but it does work when properly maintained under most circumstances, and slows the sinking process in nearly all circumstances allowing crews more time to evacuate in a n orderly fashion



 As I write this thousands of people are still without power in the U.S. North East, some have been without power for 10 days or more. At one point it was millions without power in the wake of Frankenstorm Sandy. Now many of these people are having to deal with freezing weather and snow while still without power.  American humans need to start applying the concept of compartmentalization to their utility grid. The electrical grid in particular grew rapidly and in a very vulnerable manner. Electrical wires on outdoor poles were the quick and cheap way to electrify America. There was a lot to be said at the time for electrifying America quickly and cheaply. The electrical power and distribution industry could not have grown with out customers. The more people with electricity, the more people came to appreciate the advantages of electricity. The occasional loss of electricity was rarely a problem in those days because the industry was electrifying homes that had been previously self energized units. For decades after the electrification of America began homes had lots of the old technologies in them. Most people still had their oil lamps, and lots of candles on hand. Washing and drying was still pretty much a by hand operation, cooking was in many areas for quite a while powered by cords of wood. Fire places and Franklin stoves were common. 

 It took a while for nearly everything to become electric dependent. Electric washers and dryers  bought a lot of free time and soon hand washing and wringing and hanging cloths on the line were pretty much a thing of the past for the vast majority of households by the 1950s. Radio and television entertained and informed households. By the 1980s personal computers started spreading through middle class homes.  Over the generations the "old fashioned", real working fire places , Franklin Stoves, oil lamps, and candles simply disappeared from homes. Today they are sorely missed when the power goes down for protracted periods. The power has been going down a lot of late over wider areas and for increasingly long periods of time.

 Clearly the utility grid needs to be both hardened and compartmentalized. Both processes are expensive any thing expensive that has to be paid for by private industry has to be paid for by consumers in the form of higher rates. Consumers may get a little break from lower fuel generation costs that are resulting from the use of natural gas for electrical generation. But it will take consumer pressure to get some of that extra profit redirected to to system hardening and compartmentalization. The compartmentalization concept isn't limited to just the power and other utility companies. Individuals, families, neighborhoods, counties and municipalities all have roles to play. 

 Individuals and families need to compartmentalize their home against the worst effects of power failure. A generator is a great thing to have and their possession by individual home owners is increasing, but all too often a generator gives you little more than a light in the kitchen or a couple of hours of TV reception. They can be expensive and dangerous to operate and are dependent on the availability of fuel. They have to be located outside the home and most home owners don't invest in storm prof shelters for the emergency generator.  In some cases it might be better for several families to get together and purchase a group generator and storm /flood resistant housing for the generator. The purpose of this centrally located generator isn't to power someones home but to provide a place where the contributors may charge cell phone and lap top batteries, thus restoring near normal communications on the block.

 Such emergency generator stations ought to be required by building codes into large multi- family housing developments. They would add only a a few thousands of dollars in costs to developments that typically cost millions to build. But this addition would add a major factor of habitability to any such developments allowing people to stay in their homes which survive a catastrophic event in tact, much longer, with much greater safety, lessening the impact of prolonged power outages. Home owners need to consider building in such "old fashioned " heating and cooking elements as real working fire places and Ben Franklin stoves. Personally when in human form I've compared the fire place and the Ben Franklin stove, and the Ben Franklin is a cleaner, more compact, safer heating device and much more convenient as an alternative cooking device. Additionally home owners and tenants should maintain at least a three week supply of candles with good fire protective display elements, oil lamps, and lamp oil properly stowed away from heat and flame and in proper containers. Lamp oil may violate the fire code in many apartment and condo complexes, always check with your local fire service before stocking up on any kind of combustible or inflammable material. 
File:Generac Portable Generators.png
Namazu isn't sure that every home should have one of these portable electrical generators but every block or every apartment/condo complex should have a communal generator as a cell phone and wireless computer and rechargeable battery charging station.


 In the Deep South relief from heat is a major problem in protracted power outages. The problem is aggravated by the spread of anywhere USA architecture that lacked the cooling elements of the old traditional architecture of the deep south. In the anywhere USA design high ceilings have generally given way to low to ease air conditioning and heating bills. In the old architecture high ceilings were the norm to deal with the dominant climate problem of the Deep South, moist heat. High ceilings allow heat to rise. Window space is reduced in these anywhere USA designs except where they serve a decorative function. In the Old South designs window space was floor to ceiling to promote cross ventilation. Anywhere USA design tend to become suffocating hot boxes in 90 degree (f) heat. Then they tend to retain the heat all night making the homes unlivable without electricity.

 The Old South designs were passively cooled by big porches, roof overhangs , and balconies that shaded the walls from the heat of the sun, floors to ceiling windows for cross ventilation, thick walls, and "Shoo Flies" (people or counter weighted clockwork powered fans shaped and looking a bit like a section rug hung vertically from a horizontal pole) and after electricity electric ceiling fans. There were plenty of people in the Deep South before air conditioning. Their traditional architecture from cottage to plantation manner was how how they dealt with months on end of jungle like heat. Such homes can be made quite comfortable with a just a few of the readily available and inexpensive battery operated fans. It will take a lot more of these fans to make an anywhere USA design livable. They typically will provide 40 hours of operation on four large flashlight type batteries. If you live in the Deep South you would want to have on hand a number of these fans (which retail for as little as $14) and a pile of batteries on had. If you live in an anywhere USA design building probably no amount of fan use in daylight in the late Spring through Early Fall will cool the house to livable levels. You'll need to spend the day outside or elsewhere. But as night falls if you open the house and place a few of these battery operated fans in the window facing out and a few inside circulating the air you may be able to get the day time heat out of the structure and walls and achieve the outside ambient temperature which after dark in different parts of the Deep South in the hot season may drop to the more tolerable low 80s or even 70s. You may be able to pass a comfortable night without running the fans all night, conserving battery life.

( To be continued , part 2 will complete individual and family compartmentalization and describe community and utility company efforts)
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