Navigation: Public | Members | Recipes | Store | Servicing

Sections:

Microwave Facts

How do microwaves heat food?
  Microwave energy is absorbed by many materials. Food contains moisture and the energy causes the moisture molecules to agitate at over two thousand million times per second. This creates heat and the food is cooked, thawed or reheated.

What happens to other materials?
 Microwave energy is reflected by metal and other metallic materials. It passes through materials which do not contain moisture such as glass, china, paper and plastics.

How is the energy kept inside the cooker?
  The cooker is a sealed metal box. As the energy cannot penetrate metal and escape it is absorbed by the food. The door is made of metal and often has a reinforced viewing glass insert with a perforated metal screen which ensures that the microwave remain contained in the cooking cavity. Ventilation grilles are shielded so the energy cannot escape.

What precautions are taken with the doors?
  They are not ordinary doors but electrically sealed precision units with at least two or more interlocking safety switches. If the door or latch moves a tiny fraction, the energy is automatically switched off.

How are the microwave leakage levels tested?
  All cookers are individually checked at the factory with a special meter which registers the level of emission. All qualified service engineers also use such a device. When the cooker is off, there is no energy to measure.

How far from the door does any leakage travel?
  Microwave leakage decreases rapidly with distance. For example, with the maximum permissible leakage of 5 milliwatts per square centimetre, at an arms length from the door, it would decrease to 1/1000 milliwatts per square centimetre. A milliwatt is one thousandth of one watt. In practice, such levels are even lower.

How can you tell if a microwave complies with British Standards?
 

Domestic models carry the British Electrotechnical Approvals Board (BEAB) label and other 'EC' approval.

Operating instructions should contain reference to British Standards number: BS EN 60 335-2-25 2002

Quotes
 
  • 1973, Dr James Van Allen of the University of Iowa and the discoverer of radiation belts around the earth said "My judgment of microwave oven hazard is about the same as getting a skin tan from moonlight".

  • The National Radiological Protection Board considers microwave ovens built to British Standards to be safe and have issued statements to this effect.

  • 9 September 1978, the then Minister of State for Prices and Consumer Protection, John Fraser, stated that consumers "are not exposed to any health risk when using a microwave oven made to the relevant British Standards and kept in good condition

Other Facts
 
  • There is no proven evidence anywhere in the world of any user of a microwave cooker being harmed.

  • Over 30 million microwave cookers are sold annually throughout the world.

  • 1939, Two British scientists, H A H Boot and J T Randall developed the pulse type magnetron tube for radar.

  • 1947, The first prototype microwave cooker was made in the USA.

  • 1955, The first domestic model in the USA.

  • 1958, The first commercial model for sale in the UK.

  • 1974, The first domestic model sold in the UK.


These pages are printable on A4 paper (portrait), however, multiple copies of any of these leaflets are available (at a rate of £45/100 UK only - a discount is available if you require more than 500 copies), please contact us here to discuss your requirements.