ChlorineNew guidance on estimating area affected by a chlorine release issued

Arlington, Virginia-based Chlorine Institute (CI) said that as part of its efforts to encourage safety best practices and share the latest technical information, it has issued a new version of Pamphlet 74 - Guidance On Estimating the Area Affected By A Chlorine Release. The new version, Edition 6, dated June 2015, reflects CI’s collaboration with the U.S. Department of Homeland Security’s Chemical Security Analysis Center and incorporates information obtained from the DHS “Jack Rabbit I” chlorine release field tests.   

The new guidance employs the Hazard Prediction and Assessment Capability (HPAC) model, developed and widely used by the U.S. government, with the data and findings from the field trials to provide more accurate modeling results. CI says that this multi-scenario, science-based information will assist chlorine producers and users, local emergency planning committees, fire departments, and municipalities in estimating the area affected by a chlorine release for both emergency planning and hazard assessment.

“By using Jack Rabbit data, the sixth edition of Pamphlet 74 updates the chlorine dispersion modeling used to prepare for an actual incident,” said CI president Frank Reiner. “The members of CI are committed to the safe production, transport and use of chlorine, and we were very pleased to partner with DHS Science and Technology to present the test data in this easily-used format.”

The production, distribution, and use of chlorine have strong safety records. However, in the rare event of a chlorine emergency, public and private sector emergency planners need accurate data about how chlorine will disperse in varied weather and terrain conditions. The Jack Rabbit I experimental releases performed at the U.S. Army Dugway Proving Ground in 2010 provide the most current information about the chemistry and physics associated with chlorine releases and allow planners to more effectively form emergency management and action plans keyed to local conditions and the unique properties of chlorine.  

Jack Rabbit II testing is scheduled to begin in August. CI says that in this test members, of the Institute will be working side-by-side with DHS to obtain additional data and further refine chlorine dispersion models. Once the new data are analyzed, a seventh edition of Pamphlet 74 may be required, Reiner said.

He added that all organizations that use or handle chlorine, along with emergency planners, should utilize the new edition of Pamphlet 74, available as a free download from the CI bookstore

Background
The Jack Rabbit test program was conducted at Dugway Proving Ground (DPG), Utah in April/May 2010. The program was sponsored by DHS Transportation Security Administration (TSA) with program oversight provided by the Chemical Security Analysis Center (CSAC) and test execution provided by the Meteorology Division of DPG. During the field campaign, ten trials were conducted — two pilot trials and eight record trials with releases of either anhydrous ammonia or chlorine.

— Read more in Pamphlet 74: Guidance on Estimating the Area Affected by a Chlorine Release, ed. 6 (Chlorine Institute, June 2015)