Domestic Nuclear SheltersAdvice on domestic shelters providing protection against nuclear explosions
A Home Office GuideDomestic Nuclear SheltersThis booklet is a brief guide to three basic kinds of nuclear shelter:
Further informationAdditional information about protection from nuclear
attack is to be found in the booklet Protect and Survive
available from Her Majestys Stationery Office and main
booksellers or by post from HMSO bookshops. The likely effects of a nuclear attackLight and heatA nuclear explosion produces an intense flash of light lasting some seconds which would blind anyone seeing it. The heat flash can set fire to buildings up to some distance from the centre of the explosion depending upon the haziness of the atmosphere at the time. Skin exposed to the heat flash could suffer burns. But any shelter that withstands the blast would give protection against the heat flash. Any exposed parts of the shelter made of flammable material could catch fire. Exposed plastic would not catch fire hut might distort in the heat and this could weaken the resistance of the shelter to the subsequent blast wave. Initial nuclear radiation (INR)This very penetrating radiation is emitted from the fireball within one minute of the explosion. The distances from one megaton explosions and above, at which people require shielding from INR, are less than those distances at which there would be total destruction. BlastAt the moment of explosion a blast wave would be generated, travelling at a tremendous speed and creating extremely strong winds which may last for several seconds. When the blast wave passes over a building the sudden increase of pressure and the following wind may cause the building either to explode or collapse. TremorsThe tremors or shock waves from a ground blast extend for a short distance only and would not affect buildings beyond those already destroyed by the blast. The effect on shelters below the ground would depend on their ability to withstand ground movement and on the nature of the soil. Depth in the ground, shape and flexibility would be important. FalloutAn explosion on or near the ground sucks up a large amount of earth and debris, which is vaporised as it rises to a great height and becomes high]y radioactive. It then condenses to sand-like particles which are carried along by the wind and drop to the ground. This fallout can come down very near to the explosion or may be carried by the wind for hundreds of miles. The fallout dust is usually visible to the naked eye, but it emits ionising radiation rather like X-rays, which cannot be seen or felt. Radiation is dangerous and heavy doses cause sickness or death. Fallout dust remains radioactive for some days after the explosion - and can, in certain circumstances, still he dangerous after several weeks. Bombs exploding on or near the groundWhen a nuclear weapon explodes on or near the ground, a shock like a small earthquake goes through the ground. The earth vaporised into the fireball leaves a crater around the site of the explosion. The vaporised earth falls to the ground from half an hour to up to about a day later as radioactive fallout. Bombs exploding in the airWhen a nuclear bomb explodes in the air the blast effect is more marked. The area affected will be about 30 per cent greater than a ground burst bomb of the same size. But with air-burst weapons there is no dangerous radioactive fallout - since the fireball does not touch the ground no earth is sucked up. Fig 3 - The extent of blast, fire and INR effectsAir burst (1 megaton)
Ground burst (1 megaton)
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Limit of: | A | Total destruction | x | Approx. range of INR within which shielding is vital | z | Blistering to exposed skin |
B | Irreparable damage | y | Fire zone | |||
C | Severe/moderate damage |
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Some relative protection values |
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Inches | Inches | |||
LEAD | 0.5 | STONE | 2.2 | Increased thicknesses of material reduce the intensity of ionising radiation. For example, each 2.2 in. of concrete reduces the intensity by half, so a thickness of 8.8 in. of concrete would reduce the radiation to one sixteenth of its original intensity. |
STEEL | 0.7 | BRICKWORK | 2.8 | |
TILES | 1.0 to 1.9 | SAND | 2.9 | |
CORRUGATED
ASBESTOS SHEET |
2.0 | EARTH | 3.3 | |
PLASTER | 3.5 | |||
ASPHALT | 2.2 | SLATES | 3.5 | |
CONCRETE | 2.2 | WOOD | 8.8 |
Type
1 Improvised |
Type
2 Indoor kit |
Type
3 Outdoor kit |
Type
4 Purpose built |
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Blast Protection psi (pounds per square inch) | Up to 1.5 | Up to 6 | Up to 11 | In excess of 11 |
Fallout Radiation Protection Factor | Not less than 40 | Not less than 70 | Not less than 200 | In excess of 300. Also protects against INR |
Distance from a one megaton air burst beyond which shelter will remain intact | 7 miles | 3 miles | 2 miles | Closer than 2 miles depending on design |
Ventilation | Natural | Natural or forced | Forced | Forced |
Site of installation | In house or garden | In house | In
garden. Sectional for access through house |
In garden. Appropriate access to garden necessary |
Forethought and planning | Install
in crisis. Some materials can be prepared in advance |
Obtain in peace-time. Install in crisis | Obtain
in peace-time. Install in peace time or crisis
(Can be installed as a permanent shelter) |
Install in peace-time using professional advice and help |
Approximate expected cost (1980) | Nominal if using local materials: scaffold frame about £250 | Kit
£500-£800 Bricks £300 |
Kit
£900-£1800 Plus any installation costs |
£6000-£10,000 (but more sophisticated designs would obviously cost more) |
Biscuits, crackers, breakfast cereals etc. | 2750g (6 lb)* |
Canned meat or fish (e.g. corned beef, luncheon meat, stewed steak, pilchards, sardines) | 2000g (4¼ lb) |
Canned vegetables (e.g. baked beans, carrots, potatoes, sweetcorn etc.) | 1800g (4 lb) |
Canned margarine or butter, or peanut butter | 500g (1 lb) |
Jam, marmalade, honey or spread | 500g (1 lb) |
Canned soups | 6 cans |
Full cream evaporated milk or dried milk | 14 small cans or 2 x 300g(1/2 lb) containers |
Sugar | 700g (1 1/2 lb) |
Tea or coffee (instant) | 250g (1/2 lb) |
Boiled sweets or other sweets | 450g (1 lb) |
Canned fruit, fruit juices, fruit squash, drinking chocolate | If sufficient storage space is available |
Approximate cost (mid 1980) | £15-£20 |
* Imperial equivalents are only approximate. | |
This list is based on the assumption that cooking will not be possible and that the opportunities for warming foods or boiling water may be limited. For further details see Domestic Nuclear Shelters - Technical Guidance. |
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This document is believed to be in
the public domain and was transferred to the Internet by
George Coney.
Last updated June 1999
Send mail to atomic@cybertrn.demon.co.uk