ASHRAE Standard 241 is for the Control of Infectious Aerosols.
This standard provides the minimum requirements needed to reduce the chance of transmitting diseases due to the exposure of infectious aerosols. Following this standard lowers the exposure to pathogens that could lead to sickness in building occupants.
ASHRAE 241 came about in response to the Covid-19 Pandemic to provide some national standards that could be followed and referenced to combat disease transmission. For so long the focus for ventilation was on controlling odors, providing comfort, and now the focus became how could we control infections?