Laser Safety Manual

33 Laser Safety Manual between x-rays and human tissue may cause cancer (such as leukemia) or permanent genetic effects. Contact the LSO for a collateral radiation consultation if you have questions regarding your system. Compressed Gases Compressed gases used in or with lasers also present potential health and safety hazards. Problems may arise when working with unsecured cylinders, cylinders of hazardous materials not maintained in ventilated enclosures, and when certain gases (toxins, corrosives, flammables, and oxidizers) are stored together. For additional gas cylinder safety guidelines, review the EH&S Gas Cylinder Safety Guidelines . Cryogenic Liquids Cryogenic liquids are used in the cooling systems of certain lasers. As these materials evaporate, they displace oxygen in the air; thus, adequate ventilation must be maintained where cryogenic liquids are used. Cryogenic liquids are potentially explosive due to expansion forces when ice collects in valves or connectors that are not specifically designed for use with cryogenic liquids. Although the quantities of liquid nitrogen used are small, protective clothing, eye protection, and face shields must be used to prevent freeze burns to the skin and eyes. Electric, Magnetic and Electromagnetic Fields Power supplies and other electrical equipment associated with some lasers are capable of generating intense power- frequency electric and magnetic fields that exceed published federal guidelines. Q-switches and plasma tubes are RF excited components. Unshielded components may generate RF fields that exceed federal guidelines. Appropriate warning signs and labels should be used. Explosion Hazards High-pressure arc lamps, filament lamps, and capacitors may explode violently if they fail during operation. These components shall be enclosed in a housing that is able to withstand the maximum explosive force that may be produced. Laser targets and some optical components also may shatter if heat cannot be dissipated quickly enough. Adequate mechanical shielding shall be used when exposing brittle materials to high intensity lasers.