Because of their high luminance, UV radiation (does not apply to HMI UVS) and high internal pressure during operation, HMI lamps may only be operated in enclosed lamp casings specially constructed for the purpose. Appropriate filters must ensure that UV radiation of standard HMI lamps is reduced to an acceptable level. Mercury is released if the lamp breaks. Special safety precautions must be taken. Information on safety and handling is available on request or can be found in the leaflet included with the lamp or in the operating instructions.