ASHRAE Standard 241 is the first consensus standard to set minimum requirements for control of infectious aerosols to reduce risk of indoor transmission of airborne respiratory infectious diseases. It applies to new and existing buildings and major renovations and addresses design, installation, commissioning, operation, and maintenance. Among the groundbreaking features of Standard 241 are its specification of requirements in terms of "equivalent clean air," definition on infection control as a resilient
operating mode, and inclusion of requirements for testing air cleaning systems to determine effectiveness and safety.

This presentation provides a comprehensive overview of the new standard. It includes
background on the origins of Standard 241, its purpose and scope, key definitions, requirements and how they can be met, implications for energy use, air cleaner effectiveness and safety testing requirements, development of a Building Readiness Plan, and requirements for operation and maintenance. Concluding remarks consider the broader implications of the standard and potential future developments.