When the IET included microwave leakage testing in its Third Edition Code of Practice for the Wiring Regulations in 2008 it was based on the premise that irradiation was the primary risk, whereas the main risk from a microwave oven is food poisoning caused by inadequate heating.
Microwave leakage detectors and test labels
While microwave ovens offer the convenience of quick cooking times and tend to destroy fewer vitamins than conventional cooking methods, they may also heat food unevenly and leave some parts undercooked, which risks the possibility that bacteria may survive after cooking.
Microwave leakage should be part of PAT testing procedure to ensure it is safe to use. A leakage detector helps identify the leakage levels given off by microwave ovens.
The IET has now taken microwave leakage testing out of the Fourth Edition because it is not an electrical problem, but microwave leakage hazards still exist in the workplace and PAT Testing companies will often supplement their equipment arsenal with microwave leakage detectors.
Prices start from as little as £59 + VAT for a basic microwave leakage detector, while the £125 Martindale TEK500 Microwave Leakage Detector uses a simple pass/fail design and is developed to meet national standards including BS5175:1976, Safety of Commercial Electrical Appliances using Microwave Energy for Heating Foodstuffs.
A unique feature claimed by Martindale TEK500 is its self test ability. Power output and leakage can be ascertained by using a thermometer and beaker supplied as part of the kit. Frequency of operation is 2450±25MHz, while power density range is ±1dB for plane wave of all polarisations.
The routine test is to ensure that microwave leakage remains below the recommended safe maximum of five miliwatts per square centimetre. The beaker is filled with water to the one litre mark, and initial temperature recorded from the thermometer. The beaker is then placed in the oven without thermometer and run at maximum power for 90 seconds.
When complete, the water in the beaker are given a very brief stir using the thermometer to measure final temperature and record the temperature rise to estimate the microwave heating power of the oven according to a predetermined formula.
We also bundle a microwave leakage detector with a PAT tester as part of a kit, for example the Metrel GammaPAT Basic Bundle or the First Stop Safety MemoryPAT Bundle 2.
For further information, please visit the PAT Testers Microwave leakage web page.
