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+--- Thread: How to attempt to survive a flood (/showthread.php?tid=11270)
How to attempt to survive a flood - Naveed Yaseen - 08-03-2010 05:24 AM
Pre-planning:
- Assess history and risk of flood in your area.
- Plan house and appliances so as to withstand level of worst flood in century.
- It is good to learn swimming, at least as a survival skill if not sports.
- Plan of a spot to seek refuge during flood. If the building structure is fragile and/or water speed is anticipated fast, then plan to stay away from such structures. Prefer natural solid mounds.
But if the weather at time of flood is supportive of lightning then avoid top most spots and objects with relatively sharp tips like trees or cliffs.
- Keen survivalists should keep survival kits ready for any unforeseen disasters. For example some devices have many basic needs like light, siren, radio, phone-charger, along with power options of grid, solar and hand powered dynamo, all built in one device. Like following...
http://cgi.ebay.com/SOLAR-DYNAMO-Light-Radio-Blinker-Siren-Charger-/180486882404?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item2a05db4464#ht_1207wt_930
http://cgi.ebay.com/Escape-Evade-Tactical-Military-Survival-Kit_W0QQitemZ280403179038QQcategoryZ97044QQcmdZViewItemQQ_trksidZp4012.m8QQ_trkparmsZalgo%3DMW%26its%3DC%26itu%3DUCC%26otn%3D12%26ps%3D63%26clkid%3D6657868842031891958#ht_3932wt_704
By being prepared, one may save others' lives too.
After warning, probability or visibility of flood:
- Many floods, except dam breaks, give most humans at least some minutes (usually hours) to think and prepare if they can.
- In any circumstances, try to keep nerves. Life and death are fixed in fate.
- While there may be some time to protect valuables, realize that life is always significantly more important than property. So be cautious of optimum trade-offs of risks.
- Arrange some days of drinkable water and high-energy unperishable foods, like dry-fruits, cereals or even sugar or oil.
- Arrange some shelter necessities, like blankets, umbrella per weather needs. Umbrella may be useful even in sunny weather.
- Arrange floating aids. If don't have commercial devices then improvise floating aids as explained later.
At the expected time or at first glimpse of water:
- Avoid basements because they can fill in very quickly even in light floods.
- Turn off mains of natural gas and electric power (even if electric grid is already off). If water is already in, keep hands insulated while turning off mains (e.g. by dry wood, plastic or cloth).
- Once the flood water has covered up the full width of roads, avoid moving in cabin vehicles (like cars). That is an extremely risky move. Two feet high water can sweep away very heavy vehicles. Also deeper areas usually get filled quickly but unfamiliar drivers are unable to estimate depth.
- If moving in flood, to reduce risk and intensity of electric shocks, try to stay at least an arm's length away from metallic objects. And if chest is submerged then stay as far as possible from metallic objects to minimize potential current through heart, which may cause heart arrest even with very little current.
- If you see a person caught in electric shock, if your feet are wet then do not attempt to touch him/her without dry insulation, because doing so is unlikely to save him/her but likely to result in another life lost.
Realize that 220 volts shock with wet hands and wet feet can be worse than several thousand volts shock with dry body.
How to attempt to avoid drowning in deep water:
- In all following techniques, water temperature is presumed to be not too cold, as is the case with monsoon rain driven floods.
- In all following techniques, realize that with maximum breath and maximum submerged body, it is actually lot easier to avoid drowning compared to otherwise.
A deep held breath is likely to shave off around 2kg of experienced weight.
Energy needed to keep afloat submerged parts of body is usually only like 4% of un-submerged portion of body.
- Unlike air, in water one can cling/climb/hang to objects for longer period with lesser fatigue
- Get rid of cloths as much as socially acceptable, especially heavier cloths.
- If a boat is available but it's carrying capacity is not enough to evacuate all in given time window, rather than riding on it, the same boat can support many times more people submerged to head on sides of it, provided that all sides are balanced (as are balanced in riding).
- Even non-swimmers can survive and 'walk' in water a few inches (perhaps more than 12 inches) above head, by jumping off-the-ground like...
1) In water hold breath, stand straight on ground with arms down to thighs
2) Jump off the ground like in rope-jumping (preferably by using only ankles force, but knees and hips also if more force is necessary)
3) For the short while when mouth is above water, take quick deep breath.
Not much energy is needed in jumping in water and jumping speed wont/cant be fast.
If unable to get head out high enough to breathe, then one can get even further 3-4 inches advantage if near the highest point one tilts neck backwards just bringing out nose/mouth instead of head scalp.
- Most humans, if trained, can effortlessly float in calm water for long time. This technique is called 'survival float'.
The trick is to...
1) keep in maximum breath, even in mouth and cheeks also besides lungs (volume of air is important, pressure is not important, rather fatigue-full)
2) keep nose/mouth/eyes always skywards, in such a way nose/mouth/eyes becomes upper most part of body
3) keep most of rest of body submerged, including most of head submerged except nose/mouth/eyes plane which would naturally stay above water
4) preferably (but not necessarily) body should be submerged in lying like position resistive to up-down oscillations, while still deep enough that during water oscillations the non-face parts are unlikely to emerge above water (which would send nose below water)
When conditions 1 to 3 are fulfilled, most humans do not drown nose below water, in calm waters. In slightly turbulent waters the body may oscillate above and below water (more time below water), in which case one has to sync deep but quick exhalation and inhalation when nose is above water.
http://www.flickr.com/photos/59419147@N00/33060158/
http://swim.isport.com/swimming-guides/how-to-float/
If you have not previously learned survival float and water rise rate allows some time spare from other priorities, try to practice it while water is shallow.
There is another technique of survival float, in which body and neck is bent forward to have nose inside water, occasionally bringing nose and mouth out every minute for deep but quick exhalation and inhalation.
Depending upon energy-level, to slowly move while floating, one can lightly paddle hands or feet horizontally. Vertical component of paddling needs more practice and enters more into swimming domain.
- Regardless of whether one knows swimming or survival float, still seek improvisable floating aids around. Because waters may be too turbulent for survival float, and floating aids make it easier to move around rather than just staying afloat.
Even apparently very minor looking items can save human lives from drowning, like...
- Empty plastic bottles with air-tight capable caps
- Polythene bags with knots trapping air. If a bag is big then knot to multiple air chambers for redundancy against puncture
- Styrofoam
Pre-test bottles and/or bags against leaks by submerging and watching for bubbles.
If such items are very small but many, then pack those in bag or cloth.
Put the item or bundle collection in shirt on front-side of chest. Preferably bind around chest in such a way that when floating it's upper most end would float below chin.
If binding with chest, the binding place must be at least few inches above belly button (which is approximately human body's center of mass), as up as you can go without having item floatable above chin.
If packing bottles, keep their cap sides down to backup in case of cap air-leaks.
Try to get at least 2 liters, preferably 5 liters, of total hollow items volume per average adult.
Or to calculate more accurately the needed volume, get 7% of person's weight and put that many liters hollow volume.
Exampe: for 70 kg adult, 7% of 70 is 4.9 kg, so put 4.9 liters of hollow volume.
If the flood is likely to be seawater (which is like 2% more dense than freshwater), then one may use 5% of person's weight instead 7%.
Similarly if a person's body is not extremely lean (i.e. without fat), that also eases buoyancy volume demand, by 1 to 2% depending upon fattiness of body.
If hollow items are not available then consider....
- Pots or buckets inverted to trap air (ask Sohni of Mahiwal)
- Pieces or assemblies of soft-woods. Must be soft-woods, not hard-woods, plywoods or chipboards
- Long soft pipe, with multiple air-tight knots on both ends
In case of inverted pot or buckets, hold both sides of bottom most edges. as you try to bring the pot down relative to your body your arms will feel a force which would push you up. To keep this force down to minimum to avoid fatigue, only bring pot as much down that most of your body and most of head is submerged in water except nose/eyes/mouth by tilting head backwards as if looking to sky.
In case of soft-wood, make sure there is sufficient matter (at least 10 to 20 liters wood volume per adult depending upon wood type). Hold these items in such a way that most buoyant side (e.g. the side having most wood) is upwards (which is most stable orientation). Note that finding stable orientation with human body can be complex. In case of rods or small boards most stable orientation is holding them horizontal position near shoulders, preferably divided equally across shoulders.
Again, even when using floating-aids, don't forget value of holding deep breath and value of keeping most of body submerged including most of head, as these would make floating and moving efforts less fatigue-full and less risky.
If floating aid is not improvisable but movement for non-swimmer in above-head water is absolutely critical, then as a last resort (rather than dying or letting die) if one can get a small pipe, cut/break it in such length that total inside volume of pipe piece is less than 1.5 liters (which is human exhalation/inhalation volume limit of average adult), the smaller the better, as appropriate for anticipated maximum water level above mouth. Breathe through this pipe by sealing lips around lower end and keeping other end above water. If the pipe is not stiff enough and length needs to be above arm's reach, tie upper end with some stick or rod.