Microwaves are a type of radio wave with frequencies ranging from 300 MHz to 3 GHz. These invisible waves are used for everything from cooking food to transmitting communication signals. Despite the many applications for microwave technology, these waves can pose a health hazard to anyone working or living nearby. Organizations such as OSHA regulate microwave use to protect employees in a variety of industries.
In 1970, Congress passed the Occupational Health and Safety Administration (OSHA) Act to protect U.S. workers from injury or death in the workplace. Under this act, the OSHA organization was formed as part of the U.S. Department of Labor. OSHA develops standards to improve worker safety and protect the rights of employees. All companies are required by federal law to follow OSHA standards for industry, as well as special OSHA programs related to construction and shipbuilding. Company owners who violate OSHA standards face fines or even criminal penalties. Roughly half of U.S. states also have their own OSHA programs that supplement or replace the federal standards.
OSHA standard 1910 covers microwave safety for general industry. Subpart G limits microwave exposure for workers, installers and maintenance personal. Subpart J instructs companies on controlling hazardous energy, like microwaves, in the same way that other hazardous materials must be controlled. Subpart R covers specific microwave safety requirements for the telecommunications industry.
OSHA standard 1926 includes microwave safety regulations for the construction industry. Subpart D of this standard limits workers to 10 mW/square centimeter, and outlines other microwave safety concepts for construction workers.
Workers may experience microwave exposure from a high number of sources. Most radio and phone systems rely on microwaves, as do radar devices. Microwaves are also used for cooking and food processing, especially in large scale applications. In manufacturing, microwaves may be used for sealing, curing or drying. Many welding applications also rely on microwave technology. Employees who work around large cell or radio towers are at high risk for microwave exposure, as are those who maintain, install and service television and communication devices.
According to OSHA, high-power or high-density microwaves can cause health effects similar to those associated with radiation. The most serious of these are known as thermal effects, and include blindness and sterility. Other effects are nonthermal and include problems with the immune system as well as changes in the way cells communicate with one another in the body. While most microwave exposure is believed to have some health effect, there is currently no proven risk from low-level or low-density microwave exposure--such as the microwave oven in a home.
OSHA encourages companies to form their own microwave safety programs to protect workers. As part of this program, companies must choose equipment that meets or exceeds OSHA standards for microwaves. They must identify potential hazards and decide how to protect workers from these hazards. Trained professionals should measure microwave levels to determine exposure risks, and this process should be repeated frequently to track changes. Personal protective equipment must be available for workers to limit their exposure. For the plan to be effective, all workers must be made aware of the plan and should be taught to protect themselves from microwave exposure.