THE weather has been shocking for the past few days. This is not to say that that it has been particularly bad on the contrary, indeed but the elements have conspired, as they often do at this time of year, to make life painfully hazardous for those of us susceptible to short sharp shocks' from static electricity.
The separation of electric charge by friction occurs all" the time. Indeed almost every time two materials are rubbed together, inadvertently or, otherwise, one acquires a positive charge and the other a corresponding negative one. And since most of us are moving nearly all the time, however imperceptible our motion may appear to others, the friction between different parts of our clothing, and between our clothing and other objects with which we come in contact, often causes a substantial charge to build up on our bodies over time.
An accumulated charge often leaks away to earth unnoticed if, for example, we happen to be wearing leather soled shoes as opposed to those of the rubber soled variety. Or it may be gradually, neutralised by contact with particles carrying an opposite charge suspended in the air. Sometimes, however, these processes do not work effectively, and when we stretch out a hand to touch a piece of metal the car door, a light switch, or the metal handle of a filing cabinet the pent up electricity jumps the gap there is a spark, a crackle and a slightly painful shock.
The problem is at its worst in dry and cold conditions, a combination not uncommon at this time of year. Water is a good conductor of electricity, so in a moist atmosphere it is relatively easy for the electrical charge to leak away into the air. When the air is dry, however, the charge accumulates, ready to follow the easiest direct path to earth when given half an opportunity. Temperature is relevant because of the effect of central heating if cold outside air has a relative humidity of, say, 40 per cent, this figure may drop to 15 or 20 per cent by the time the air has been drawn inside and heated for internal circulation.
Some individuals are more prone to static shocks than others. At the strategic level, the problem can be alleviated wearing clothes, and particularly shoes, of natural rather that synthetic materials. Tactically, a useful ploy is to have a metal object, like a coin, in hand before attempting to touch any object made of metal then, just before contact is made, you will see a spark jump from the coin to the adjoining metal, effecting a painless, albeit only temporary, discharge.