How Copper Door Handles are Putting a Stop to Germs
SHUT THE DOOR ON GERMS
Keeping door handles sanitary are instrumental in stopping the spread of many infections. Some materials, e.g. brass, copper and silver, are actually slowly poisonous to many germs. The exact mechanism that kills germs is unknown, but is commonly thought to be via the oligodynamic effect, perhaps by some other electrostatic effect.
The oligodynamic effect (from Greek oligos "few", and dynamis "force") is a biocidal effect of metals, especially heavy metals, that occurs even in low concentrations. The health effect was known in India for more than 2700 years as their ancient texts prescribe brass utensils for purity of water and good health.
Brass and copper, for example, disinfect themselves of many door handle bacteria within eight hours. Other materials such as glass, porcelain, stainless steel and aluminium do not have this effect. Self-disinfecting door handles are particularly important in hospitals, but useful in any building.
Copper has been exploited for health purposes since ancient times. Egyptian and Babylonian soldiers would sharpen their bronze swords (an alloy of copper and tin) after a battle, and place the filings in their wounds to reduce infection and speed healing.
COPPER IN MEDICAL FACILITIES
Studies worldwide have shown that, with routine cleaning, when copper alloy is used on regularly touched surfaces in busy wards and intensive care units, there is up to a 90% reduction in the numbers of live bacteria on their surfaces. This includes bed rails, chair arms, call buttons, over-bed tables, IV poles, taps and door handles.
Studies in three hospital intensive care units in the US also showed a remarkable 58% reduction in infection rates. So, unsurprisingly, copper alloy touch surfaces are now being deployed worldwide in airports, trains, train stations, busses, restaurant kitchens and gyms. The new Francis Crick Institute in London is kitted out in copper alloys, supporting its foresight and vision as a world-leading research centre for the public good.