Safety specifications: In the United States and Canada, SCBAs used in firefighting must meet guidelines established by the National Fire Protection Association, NFPA Standard 1981. If an SCBA is labeled as "1981 NFPA compliant", it is designed for firefighting. The current version of the standard was published in 2007. These standards are revised every five years. Similarly, the National Institute for Occupational Safety and Health (NIOSH) has a certification program for SCBA that are intended to be used in chemical, biological, radiological, and nuclear (CBRN) environments. See: NIOSH Approved SCBAs. Any SCBA supplied for use in Europe must comply with the requirements of the Personal Protective Equipment Directive (89/686/EEC). In practice this usually means that the SCBA must comply with the requirements of the European Standard EN 137: 2006. This includes detailed requirements for the performance of the SCBA, the marking required, and the information to be provided to the user. Two classes of SCBA are recognised, Type 1 for industrial use and Type 2 for fire fighting. Any SCBA conforming to this standard will have been verified to reliably operate and protect the user from -30⁰C to +60⁰C under a wide range of severe simulated operational conditions. The Royal Australian Navy uses the Open Circuit Compressed Air Breathing Apparatus (OCCABA), a backpack-style, positive pressure breathing apparatus, for fire-fighting roles