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F 311"1 NEW IMPROVED FIRE CODES EASE STORAGE AND USE REQUIREMENTS FOR CHLORINE GAS Users of chlorine regulated by the newly created 2003 Inter- national Fire Code and 2003 Uniform Fire Code are pleased they are no longer required to have a scrubber when storing or using 150 -lb cylinders or one -ton containers of chlorine gas. A scrubber usually consists of a scrubbing chemical (typically caustic soda) and a blower to draw contaminated air through the solution circulated by a pump. For indoor and outdoor storage, the need for a scrubber is eliminated if ... 1. Chlorine cylinder valve outlets are equipped with gas -tight outlet caps. 2. Where approved containment vessels or containment sys- tems capable of fully containing or terminating a release are available or that are capable of being transported to the leaking cylinder, container or tank. For indoor and outdoor use, the need for a scrubber is eliminated if ... 1. An approved automatic - closing fail -safe valve is located im- mediately adjacent to and downstream of the active cylinder valves.The fail -safe must close when gas is detected at the permissible exposure limit. 2. Where approved containment vessels or containment sys- tems capable of fully containing or terminating a release are available or that are capable of being transported to the leaking cylinder or container. Plant operators find that fail -safe valves and containment vessels require little or no maintenance. A scrubber system may require extensive maintenance, includ- ing testing and replacement of caustic, belt adjustments, sheave alignment, exhaust airfan adjustments,fan wheel service,pump repair and seal replacement. A fail -safe valve is typically described as a 1/4 turn ball valve that is spring loaded, always fails in a closed position and does not rely on any electrical power or backup emergency power to close the valve.A valve that does not have all these characteristics is unsafe by comparison. Unmanned sites located in populated areas are especially in need of a system to process chlorine from cylinders that will release little or no chlorine gas to the surrounding community. Total containment vessels used for processing chlorine from a cylinder or ton container that is enclosed within the vessel is the only system that the worst -case offsite release of toxic gas by 97 percent, making it by far the safest method for processing chlorine. Scrubbers and fail -safe shutdown valves provide no reduction in the offsite area affected when conducting RMP studies to as- sess the effects of a release. Sites within sparsely populated areas may find the cost of installing a scrubber or total containment system used for the processing of cylinders or ton containers to be out of the ques- tion because of budget constraints.The new codes allow the use of less expensive automatic closing fail -safe shutdown valves located immediately adjacent to and downstream of active cyl- inder valves.The fail -safe valves must close when a gas detection system detects a release. All sites storing cylinders or tons must have available to them emergency containment vessels or systems capable of contain- ing or terminating a release from a leaking cylinder. If the emer- gency vessel is not located at the site, it must be capable of being transported to the site of the leaking cylinder.A trailer mounted emergency vessel would typically be transported to the site by the emergency responder. Communities with multiple sites need have only one emer- gency vessel available to handle leaking cylinders; although locating a vessel at every site provides added safety. The emergency vessel must be designed to process the entire contents of the leaking cylinder at the treatment site to prevent transporting a leaking cylinder or ton container. Small communities may, through association with others, share the cost of a containment vessel system, trailer mounted so as to allow compliance at a lower cost. Containment vessels satisfy the definition of a treatment system in the codes, because, once contained within the vessel, the total contents from the leaking container can be put into process at the site at a safe controlled rate. As in all cases related to fire codes, the local fire department should be consulted to determine their requirements. Fail -safe shutdown valves and 150 -lb and one -ton total containment vessels, both stationary and trailer mounted for emergency containment and processing, are available through TGO Technologies, Inc. TGO (Toxic Gas Ordinance) Technologies, Inc. (800) 543 -6603 www.tgotech.com email: sales @tgotech.com 19