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Microwaves are part of the electromagnetic spectrum; they range in frequency from 300 megahertz (MHz) to 300 gigahertz (GHz). Microwaves are used for communications, radar, intrusion alarms, door openers, and medical therapy, but they are most commonly used for cooking.

Metal reflects microwave radiation, but dry nonmetallic surfaces allow microwaves to pass through with little or no heating effect. Organic materials, however, are extremely heat conductive. Because microwaves can penetrate organic materials, including tissues, thermal burns and other effects may result from microwave exposure.

NOTE: Microwave ovens are very safe when kept in good working condition and used properly. They do not serve as a source of exposure to harmful microwaves.

Even though microwave ovens are not a source of harmful radiation exposure, they should be properly used and maintained.

  • Do not put metal objects (including aluminum foil) into a microwave oven.
  • Do not use a microwave oven if it is damaged.
  • Ensure that the seal on a microwave oven is tight, intact, and in good condition (i.e., not charred or distorted).
  • Ensure that microwave ovens are clearly labeled for laboratory use or food preparation only.
  • Microwave ovens should only be repaired by trained personnel.

6. Radiation-Producing Devices

Radiation-producing devices such as X-ray machines, electron microscopes, and particle accelerators are regulated through the BRC, Texas Department of Health. Radiation-producing devices (other than human and veterinary diagnostic devices) shall be interlocked to prevent access to the unshielded beam during normal or routine operations.

IMPORTANT: The door(s) to a room where a radiation-producing device is located should be posted with a radiation warning sign, unless the device is totally self-contained.