THE H BOMB

[Music] [Music] so [Music] today we live in the shadow of a monstrous writhing cloud of mushroom-like shape some days the shadow seems to be less opaque and the sunlight filters through on other days it becomes heavy with apprehension and the threat of total annihilation becomes real that threat is always with us we shall be both older and wiser people when the day comes for the shadow to retreat out of our imagination until that day comes we must prepare ourselves each one of us to face the appalling catastrophe that may be our supreme testing time in the history of civilization it is human nature to wish to save life no matter how great the danger involved or how impersonal the life that is at stake in peacetime we look to the trained professional to save our lives in wartime those of us who are needed on the home front must all become professional life savers the days have gone when we could sit back and say this has nothing to do with me a nuclear war will have something to do with every single person who is able to stand up and walk everyone must have some idea of what to do an untrained helper however courageous or willing will be a nuisance to his fellow workers and might well prove to be a source of danger first we must accept the fact that we shall all be in it and secondly we must ask ourselves what we individually can do to help in this respect we must find out the nature of the beast learn a little of its effects and how best to combat them no matter how large be the area of destruction there will always be much which can be done in fact the greater the destruction the more outside aid will be necessary in a simple isolated incident as was experienced in the last war when an he or incendi bomb destroyed a building the rescue work and firefighting were dealt with by local resources as the missiles became more powerful and the area of destruction increased so the civil defense organization became more complex no longer could local resources deal effectively with the situation outside aid was directed by the controller to the damaged areas and many lives were saved as well as homeless people catered for by highly trained specialists in the art of rescue and welfare at the height of the enemy's bombardment on our cities firefighting appliances were being called from southampton to help london and later from london to help portsmouth mobile civil defense columns were constantly being directed to new areas of devastation the call went out for help and it was never once left unanswered when peace returned to our islands we had hardly taken stock of our resources when we were confronted with a new danger more frightful than ever before our vocabulary became charged with terms of this atomic age we learned to speak of ground zero of heat flash of gamma radiation and mass destruction by blast we learned to think in terms of miles instead of streets and buildings of many thousands rendered homeless instead of hundreds gradually our minds began to accept the problems created by this new horror we learned to plan our campaign by working on a set unknown pattern of destruction the experts chose one particular size of bomb and called it with all the impersonality that only scientists could muster the nominal bomb this nominal bomb was the one used at nagasaki it represents the power of twenty thousand tons of tnt it became a suitable yardstick to which one could add or subtract notes to describe the size of the missile no matter whether the bomb turned out to be half the power of the nominal or twice the power of the nominal the type of destruction remain the same only the scale of destruction was altered to the great majority of civil defense workers the size of the bomb is only of academic interest whether a person being rescued from fallen debris has been trapped as a result of a larger or smaller the nominal bomb is of little consequence what matters is that the person be rescued quickly and be cared for while the rescuers turn their attention to other pressing needs today with the shadow of a hydrogen bomb hanging over us the problem remains the same but civil defense will have to rely on outside aid to a very much larger degree than before the hydrogen bomb as it is commonly called since the fusion of hydrogen isotopes is part of the explosive process has no mysterious characteristics of its own its effects are in the main similar to those of an atom bomb but on a very much larger scale it is therefore better to refer to it as a so many times nominal bomb a nominal bomb you will remember is equal to twenty thousand tons of tnt we are told that a five hundred times nominal power would be a realistic figure to work on giving a power equal to ten million tons of tnt or 10 megatons so let us apply the appropriate scales and see what sort of a problem we might have to tackle you may remember that in the film the atomic bomb the three effects of the explosion were taken separately we were told that the first of these effects that of heat came from the searing flash at the moment of the explosion with a nominal bomb detonated at a height of one thousand feet we learned that only those people exposed to the flash within a distance of two and a half miles from ground zero would suffer skin burns those taking cover would be unharmed though at ranges up to a mile and a quarter the buildings they were in might have caught far you may also remember that this tremendous burst of heat lasted for only a second or so with a 500 times nominal bomb this effect lasts for something like 20 seconds and can therefore hardly be called a flash as one might expect with a more powerful bomb the range of the effects increases and with an air burst at the appropriate height fires may be started out to a radius of about 15 miles on the other hand with the ground burst the main fire zone may only extend to about 10 miles because a lot of heat would be absorbed in the crater as we shall see later it is much more likely that bombs of such power will be burst on or near the ground than in the air the precautions that may be taken to minimize the effects of heat are exactly the same as given for the nominal bomb do you remember them the white washing of window glass the fitting of shutters and dipping curtains in fire resistant solutions the considerable increase in range brought about by larger bomb need not necessarily result in a proportionately greater number of casualties from the effect of heat with adequate warning everybody should be under cover but even those people who are caught out in the open at the moment of the explosion could if they took cover immediately avoid part of the full effect providing they were some distance from ground zero next in the atomic bomb film we learned about radioactivity immediate radiation and residual radiation for immediate radiation we were told that gamma rays were the chief source of danger neutrons could for practical purposes be disregarded with a 500 times nominal bomb the same lesson holds good but to those in the open the range of a 50 lethal dose is increased from three quarters of a mile up to two and a half miles some damage can of course be caused to people in the open from immediate gamma radiation at distances further than two and a half miles but there will be no significant effect beyond about four miles from ground zero this increase in range is perhaps not as great as one might have supposed the reason for this is that the gamma rays are scattered or dissipated in the atmosphere and become less concentrated with distance it should be appreciated that with a five hundred times nominal bomb the two and a half mile radius is in any case inside the limit of total destruction of houses with a ground burst however the second form of radiation residual radiation becomes a much more serious hazard you may remember that we were warned that should a nominal bomb be exploded at ground level then dust and atomized rubble would be made radioactive and be scattered over a wide area notably downwind of the explosion this was termed the fallout to do the maximum damage by blast an atomic bomb should be airburst but with the much more powerful hydrogen bomb the range of the blast damage is so great by comparison with any likely built up target area that a ground burst can do all the destruction required and at the same time produce a tremendous fallout problem as a bonus therefore this more powerful type of bomb is more likely to be burst on or near the ground than in the air when this takes place thousands of tons of atomized earth stone brick and steel are sucked up into the mushroom cloud and become highly radioactive of this material falls back into the area from which it came but the lighter particles are carried with the wind and may not fall to earth until many hours later and possibly many miles away downwind this fallout is thus a danger not only to the area surrounding ground zero but to other communities at considerable distances away we know for example the japanese fishermen received serious doses of gamma radiation from fallout after an american test when they were about 70 miles downwind from the explosion fortunately even the average small house in this country gives a good measure of protection from fallout and this could be improved by quite simple measures refuge rooms can be made in buildings and slit trenches with overhead cover provide a substantial means of protection much thought is being devoted to working out all these details which will in due course be made public the public must be prepared to have to stay indoors for at least two days and possibly longer in some areas until the radioactivity has decayed sufficiently for them to come out for short periods this means that houses would have to be stocked with food and water and preferably a battery-operated radio so that contact with the outer world can be maintained dairy cattle should be kept under cover and if possible other livestock as well cooperation between civil defense and the meteorological services should make it possible to give sufficient warning to those people living downwind of an explosion to enable them to take proper precautions next we come to the effect of blast the categories of damage used in the original atom bomb film have been slightly changed with a nominal bomb burst over a british city there would be total destruction of houses out to a radius of half a mile from ground zero beyond this irreparable damage out to three quarters of a mile severe to moderate damage out to two miles and light damage out to a radius of three miles so with a five hundred times nominal bomb detonated at ground level these distances are some three and a half miles for total destruction of houses some five miles for irreparable damage some 13 miles for severe to moderate house damage and 20 miles for light damage this distance will bring the limit of blast effects out into the open country for nearly all british cities it is because the whole of an attack city will be damaged to some degree that we must think in terms of help from outside taking all three effects of a 500 times nominal bomb detonated at ground level let us try and see the problems that would confront us as we neared the area of damage the first and most serious consideration is residual radiation from fallout which will impose delays on progress since the area of heaviest contamination will be spread downwind and fallout will occur far beyond the area of blast damage approach will probably have to be restricted to the upwind and crosswind sides of the city for the first few hours once the radiological safety organization allow controlled entry into the area we should find something like this as we approach within about 20 miles of ground zero we should encounter some damage to roof tiles and slates and to light structures such as garden sheds and garages broken windows would have been evident long before we reached this 20 mile radius for the next seven miles damage would be increasing so that at about 13 miles from ground zero we should find widespread damage to houses like this assuming that residual radioactivity permits us to continue we should over the next eight miles traverse an area of moderate to severe damage until we reach the houses suffering irreparable damage some five miles from ground zero in the course of this last eight miles from thirteen to five miles from ground zero we should encounter two further obstacles in addition to the invisible barrier imposed by residual radioactivity first the debris in the streets would steadily increase from slates and tiles and glass at the beginning to heavy debris from demolished buildings nearer the five-mile radius secondly we should have to traverse the main zone of fires which would be between three and a half and ten miles from ground zero the mass of debris in the streets at five mile radius would be so deep that little further progress would be possible unless large open spaces wide roads or railway tracks or broad waterways where usable even with such means of access residual radioactivity in this area would be so intense that reconnaissance teams would be unable to penetrate much further for many hours it must be accepted that little or no rescue work would be possible within three or four miles of ground zero where houses would be completely demolished and even the strongest buildings severely damaged to recap the three effects of a 500 times nominal bomb detonated at ground level on a british city first there is heat with a far zone from three and a half to ten miles second there is radiation immediate radiation out to four miles and residual radiation out to 11 miles or more in the target area and the grave fallout menace downwind third there is the damage caused by blast giving total destruction out to three and a half miles irreparable damage out to five miles severe damage out to 13 miles and light damage out to 20 miles the picture may well be considered alarming but remember it is based on the latest scientific data it is as well to face up to it and plan out action accordingly the large increase in the scale of damage produced by a more powerful bomb presents a host of new and complex problems to those responsible for civil defense administration they have to consider mobile control centers and mobile columns of rescue and welfare teams they have to consider the quickest and most efficient means of bringing soccer to a stricken city faced with the inevitable delay brought about by residual radiation but to the likes of us you and me and every willing helper who has been trained the individual problem is no different there would be many hundreds of thousands of trapped and injured waiting for us to rescue them there would be an even greater number of homeless each one requiring advice and guidance as to where to go so that they may be cared for and fed in an area free from the hazard of radioactivity if nuclear war should come to our islands and some of our cities be subjected to this most terrible of man-made catastrophes are we in other more fortunate cities or those of us who live in the heart of our countryside are we to sit back complacently and say bad luck jack i'm all right [Music] you