As scientists learn more about the COVID-19 virus, opinions are changing on how it is spread from person to person, and that has implications for how to reopen buildings safely.
Emphasis to date on protocols for reopening buildings has focused on surface cleaning and occupant density. But, if as some scientists suspect, the virus can live for at least three hours in aerosols—tiny particles that can be carried through the air for long distances—HVAC systems could play a key role in spreading the virus. There are opposing views on whether aerosols actually can transmit the virus, but if they do, then ventilation systems could spread the virus through unfiltered re-circulation of indoor air.
In April, ASHRAE addressed the issue of possible aerosol transmission with recommendations that include:
· Maintain a relative humidity of 40% to 60% inside buildings instead of the usual 20% to 40%.
· Install air filters rated at least at MERV-13.
· Minimize re-circulation of indoor air, and bring in outside air either by mechanical means or by opening windows.
The humidity recommendation was made because higher humidity makes aerosols heavier, causing them to drop to the floor faster. ASHRAE has also recommended that the intake of outside air be set to the highest level permitted by the mechanical equipment. Some specialists recommend a full re-commissioning process for reopening buildings.
Related Stories
| Aug 6, 2014
Loudoun County, Virginia may dump green building requirements
Loudoun County, Va., supervisors may do away with a county policy that requires LEED Silver certification on new county buildings.
| Aug 6, 2014
$300 million mixed-use project in Chicago’s medical district wins key approval
The Illinois Medical District Commission approved a 1.16 million-sf, $300 million mixed-use project in Chicago’s Illinois Medical District.
| Aug 4, 2014
Facebook’s prefab data center concept aims to slash construction time in half
Less than a year after opening its ultra-green, hydropowered data center facility in Luleå, Sweden, Facebook is back at it in Mother Svea with yet another novel approach to data center design.
| Jul 31, 2014
LEED Dynamic Plaque gives owners and tenants ability to monitor building performance
The LEED Dynamic Plaque could aid certified buildings in maintaining performance with up-to-date information about water and energy use, waste reduction efforts, occupant experience, and other green performance categories.
| Jul 31, 2014
Gypsum Association releases updates to wallboard repair standards
The Gypsum Association released updates to both GA-221 Repair of Joint Ridging and GA-222 Repairing Screw or Nail Pops standards publications.
| Jul 31, 2014
Cambridge, Mass., is latest locale to require energy usage disclosure
The City Council of Cambridge, Mass., approved the Building Energy Usage and Disclosure Ordinance (BEUDO) that requires benchmarking and disclosure of building energy performance for large commercial, institutional, and multifamily buildings.
| Jul 31, 2014
Stalled $1.5 billion Miami mixed-use redevelopment project advances
A long-delayed $1.5 billion mixed-use development in Miami moved ahead after city planners approved the project’s first phase.
| Jul 30, 2014
USGS updates National Seismic Hazard Maps
The U.S. Geological Service recently released an update of U.S. National Seismic Hazard Maps that reflect the latest analysis of where future earthquakes will occur, how frequently they may occur, and their strength.
| Jul 23, 2014
Fairfax County, Virginia toughens green standards
The Fairfax County Board of Supervisors recently strengthened its green building policy, requiring higher standards for residential, retail, office and other construction projects seeking approval for rezoning.
| Jul 23, 2014
Berkeley National Lab’s FLEXLAB is a test bed for energy efficient office design
FLEXLAB, short for the Facility for Low Energy Experiments, opened this summer at the Lawrence Berkeley National Laboratory.
