Identification of the Chlorine- and Bromine-Based Biocides - Task 1 of the NESC Assessment of Biocide Impacts on Life Support (LS) and Extravehicular Activity (EVA) Architectures

National Aeronautics and Space Administration (NASA) has undertaken an Assessment of Biocide Impacts on Life Support (LS) and Extravehicular Activity (EVA) Architectures, producing an NASA Engineering and Safety Center report by the same name. The purpose of the report is to evaluate whether the current iodine-based biocide should be replaced due to the need of removing that iodine prior to consumption, if silver biocide is an appropriate replacement, or if there is another better biocide choice. This paper is a supporting document detailing the chlorine- and bromine-based biocides found for Task 1 (Identify and Document Available Forms of Biocidal silver, bromine, and chlorine). This paper identified eleven chlorine-, eight bromine-, and one mixed chlorine- and bromine-based biocides and documented their many chemical, biological, and application properties. Additionally, five qualification criteria were developed to evaluate the biocide s acceptability. Based on this evaluation, ten of the twenty biocides found were not recommended for further evaluation in Tasks 2-4, six are being recommended after passing all qualification criteria and four are being recommended requiring further review.