NASA Establishes Guidelines for Safe Levels of Chemical Contaminants in Spacecraft Air and Drinking Water

4 min read The JSC toxicologists establish guidelines for safe and acceptable levels of individual chemical contaminants in spacecraft air (SMACs) and drinking water (SWEGs) in collaboration with the National Research Council’s Committee on Toxicology (NRC COT) and through peer-reviewed publication. The framework for establishing these levels is documented forSMACsandSWEGs, and recent refinements to theMethodsreflect current risk assessment practices. In addition to official SMACs used for the evaluation of spacecraft air, JSC toxicologists set interim 7-day SMAC values that are listed in NASA Marshall Space Flight Center’s Materials and Processes Technical Information System (“MAPTIS”), which is used to evaluate materials and hardware off-gassing data. A table listing the official NASA SMAC values is published inJSC 20584 (PDF, 1MB)(Last revised – June 2024). References for the published values are provided below: