ASHRAE remains at the forefront by providing resources that are instrumental in safeguarding indoor environments. As COVID-19, flu, and RSV persist, providing clean air in buildings has become even more critical. ASHRAE Standard 241-2023: Control of Infectious Aerosols, continues to empower building owners, operators, and professionals to proactively reduce risks for occupants during peak virus seasons.

First published in June 2023, ASHRAE Standard 241 establishes minimum requirements to reduce the airborne transmission of viruses like SARS-CoV-2, the flu, and other pathogens. This standard applies to various building types, including single- and multi-family homes, offices, schools, and healthcare facilities. Recognized as the first consensus-based, code-enforceable standard of its kind, it has been praised by former White House COVID Response Coordinator Dr. Ashish Jha as "one of the most important public health interventions seen in years." The potential for federal adoption highlights its crucial role in protecting public health across the built environment.

"Standard 241 reinforces ASHRAE’s dedication to improving the health and well-being of building occupants,” said 2024-25 ASHRAE President M. Dennis Knight, P.E., BEMP, Fellow Life Member ASHRAE. “The Society supports legislation to improve indoor environmental quality (IEQ), which we know is a long-term solution in mitigating disease transmission and this standard is a foundational piece. By making the integration of strategies to control infectious aerosols the norm, we are helping to create safer indoor environments.”

Standard 241 provides detailed guidance on the design, installation, commissioning, and maintenance of HVAC systems to control the spread of infectious aerosols. It covers ventilation rates, filtration, air cleaning technologies and includes a building readiness plan to evaluate the performance of existing or new HVAC systems. Additionally, the standard addresses Legionellosis risks by focusing on potable water systems, decorative water features, whirlpool spas and cooling towers, with appendices on U.S. drinking water regulations, Legionella testing and personal protective equipment (PPE) guidance. Further building occupant safety guidance can be found in ANSI/ASHRAE Standard 188, Legionellosis: Risk Management for Building Water Systems.

ANSI/ASHRAE Standard 62.1, Ventilation and Acceptable Indoor Air Quality and Standard 62.2, Ventilation and Acceptable Indoor Air Quality in Residential Buildings are also key resources for tackling poor indoor air quality (IAQ) in both commercial and residential buildings, impacting health, comfort, and productivity. These standards provide three compliance methods: prescriptive, performance-based, and natural ventilation approaches.