NASA's Office of the Chief Health and Medical Officer (OCHMO) orchestrated a comprehensive review of hydrogen sulfide (H2S) Spacecraft Maximum Allowable Concentration (SMAC) values to ensure the safety of spaceflight crews, particularly with the upcoming Artemis missions. The working group, comprising experts in toxicology and epidemiology, aimed to endorse proposed SMAC levels, review a draft manuscript, and provide additional insights into H2S toxicity for spaceflight programs. The review acknowledged the possible presence of H2S in spacecraft during lunar sample return missions, highlighting its potential health effects ranging from irritations to unconsciousness. The panel endorsed most proposed SMAC values while suggesting the elimination of the 1000-day SMAC due to practical challenges in maintaining such low concentrations. They emphasized the need for individualized attention for private spaceflight participants and recommended the use of passive dosimetry technology for long-term monitoring. Following the panel's recommendations, the Exposure Limits for Hydrogen Sulfide in Spaceflight were revised in January 2024, setting the stage for safer space missions with well-defined SMAC values.