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During the massive task of post war reconstruction here and in Europe and the subsequent rise in livng standards throughout the developed world, a number of significant changes occurred in house building design, construction and materials. Traditionally homes were generally built from local natural materials, were loose fitting (ie draughty), wisely located and minimally serviced. The contemporary modern home has had a large number of synthetic materials introduced into it. Many of the building products are trated with formaldehyde and other pesticides are used during construction almost as a matter of course. The most significant factor though is the change in the method of heating. The traditional home was inefficiently heated by solid fuel fire, providing radiant heat to warm the occupants, the contents and the mass of the building but not directly the air. That was leaving the room up the chimney at a rate that provided roughly six air changes per hour for each room with a fire lit. The contemporary home is now heated by convection, from the "radiators" of a central heating system. The air in the home is being used as the medium for heating the occupants and the contents. Homes therefore aspire to be air tight. Draughts are sealed and ubiquitous gas fire central heating is found to be the cheapest and most efficient source of heat, but does it measure up to the parameters of a Healthy House. The contemporary home can be found in practice to have ventilation rates as low as 1/10 air change per hour. At this level of air change even low emissions of air borne pollutants can build up over time to become problematic. The use of aerosols, gas cookers, vacuum cleaners and smoking combined with the out-gassing from the synthetic materials and the insecticides and fungicides within a sealed home leads to levels of air polution which can result in real possibility of sickness among its occupants. Asthma is a desease which is increasing in spite of efforts of modern drugs therapy and could be related in some cases to the problems mentioned above. The American Enviromental Protection Agency now considers Radon and Radon daughters to be the second cause of lung cancer after smoking . This isn't confined to houses, at a commercial level the problem has been quantified by publication last june of the House of Commons Committee on the Enviroment's Report, titled 'Indoor Air Pollution'. This far ranging enquiry looks at the sources of a problem which is costing the country between 330 and 650 million pounds in business inefficiency every year. 'Sick Building Syndrome' is known by managers and employees alike and when they return home from work they apply similar criteria to their home enviroment and seek not efficiency but health and vitality for themselves and their family. Some developed countries (without large cheap supplies of natural gas) have had to be more rigorous in their evaluation of domestic heating systems. Sweeden in particular has made far reaching technical advances in the development of heat recovery from the ground and air, both of which are a more sound ecological alternative to our short sighted reliance on cheap natural gas. Their approach to
the indoor domestic enviroment has been to look back at the traditional
house and incorporate large low surface temperature radiant heat sources
within the floor or ceiling, rather than the solid fuel fireplace and
chimney. Once the air itself is not used as part of the heating system
then its movement can be organised naturally or mechanically to provide
the occupants with sufficient fresh air as required by their numbers and
activity. The benefit is that the pollution build up from the sources
mentioned above can be kept low without loss of heat These low temperature radiant heating systems are available in this country but due to the dominance of cheap supplies of natural gas, their additional capital installation cost means that consumers usually opt for the cheaper convection system unless the enviromental and health advantages are made clear to them. The change to low temperature radiant heating augmented with natural or mechanical ventilation is the fundamental key to the internal enviromental problems in contemporary homes. Household dust itself, dust mites, radon and radon daughters, bag filter vacuum cleaners, fitted carpets, formaldehyde and ozone are pollution problems whose significance is exacerbated by conventional central heating. It is true that many of the books (mentioned in the bibliography) suggest a retunto less toxic more natural material and finishes within the house but wihout the change in heat source and consequent comfortable increase in ventilation rates introducing fresh air into the home, they are peripheral. At the same time as central heating has become the norm in the contemporary home, a fundamental but invisible element has enterd into our homes and work places: electromagnetic energy. The consumption of electricity is considered a key parameter of economic development: the city of New York for instance, uses as much energy as the whole continent of Africa. The last 25 years have seen an unprecedented increase in the use of this form of energy within the home. Its uses can be utilitarian, decorative, illuminating entertaining and its safe, or is it? When I was a boy, I took great delight in having my feet x-rayed in Oxford Street shoe shops as many times as I wanted. Safe levels of x-rays (ionizing radiation) were soon removed as the effect of these fields of energy became obvious. The difference between ionizing radiation (x-rays) and non-ionazing radiation (electromagnetism) is only one level of energy transmitted. Both are part of the overall electromagnetic spectrum. Today, safety levels in non-ionazing radiation; electric and electromagnetic fields, are being continually revisited and lowered, in same cases reluctantly, to levels (in Europe) where many day to day tasks at work and home involving electricity are considered to be biologically harmful if carried out for long periods. In 1992 the EEC, Display Screen Equipment Directive requires, as part of its proposals for VDU screens, that they should emit, 'negligible radiation'. The UK Health and Safety Executive is at present considering its interpretation of this Directive and although no specific safety levels had been set throughout the EEC, Sweeden has its own Electric Field Emssion Standard of 2.5v/sq.m.at 50cm. These levels can be eceeded by sitting at an ordinary VDU screen, an electric typewriter or TV computer game. The exceptional usefulness of electricity in the home will make removal of this health hazard difficult if not impossible. What is important in the Heathy Home is to incorporate witthin the electrical system many of the shielding devices presently available and in common use in Europe. Double insulated electrical cables can be used when installing the electric service and double pole switches can be used to cut down the electric field from wiring and appliances in the home when not actually in use. Research by Roger Coghill (1) indicates that particular attention should be paid to enabling the sleeping place of the occupants to be free of electric fields while they are asleep. The mechanism of cell replacement and generation appears to take place during periods of 'paradoxical sleep'. At this time the brain strangely enough becomes super active and the body inert, and the brain is considered to transmit its own 'field' or radio signal to the body to instruct and organise the cell metabolism taking place at the time. In this process it is therefore a source of biological stress and an opportunity for cell aberration. To impose on the activity of the brain an external electric field of 50 herts (or 50 cycles per second) such as would be generated by a 13A double socket 18 inches from your head. For some time voltage demand switches have been routinely incorporated in European domestic electric services which automatically reduce the voltage in the wiring when no appliance is being used. The use of these demand switches and the avoidance of ring circuits in the wiring layout can to a greater and lesser extent, reduce the overall 50 hertz field within the house generally, or specifically around the sleeping areas. If overhead electricity power pylons or single electric cables are in the vicinity of the house precise measurements of the electromagnetic fields should be taken to ensure they are within the safety levels mentined previously. To understand the significance of electromagnetic fields to us we have to realise that we live at the bottom of an ocean of energy. We are ourselves a bio-electric system and we should therefore treat non-ionizing radiation as created by domestic electricity service with circumspection. This naturally occuring ocean of energy has at the surface of the earth perturbations and grids patterns within it, the exact position of which should be ascertained by dowsing prior to positioning the house and the sleeping or working places within it. Disturbances in this enrgy field can also be created by geophysical faults and underground streams. These factors and orientation to sunshine and prevailing wind should be taken as the basis of orientation and sitting of the healthy house. (1). His work generates disputation, to help forming your own mind about it, go through the links of : http://www.cogreslab.co.uk/our_research.asp |