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
| Dec 26, 2013
USGBC recognizes Ohio for achieving 100th LEED-certified public school
The U.S. Green Building Council (USGBC) has recognized the state of Ohio and the Ohio School Facilities Commission (OSFC) on the LEED certification of the 100th public school building in the state.
| Dec 26, 2013
WDMA launches project to create ISO-compliant architectural doors
WDMA's National Architectural Door Council has initiated a project to create ISO-compliant Product Category Rules for architectural wood flush and stile and rail doors
| Dec 19, 2013
Defense Department okays Green Globes standard for DoD facilities
The Green Globes certification program from the Green Building Initiative can be used for the renovation and construction of Department of Defense facilities following agency endorsement.
| Dec 19, 2013
New York City proposal may boost standards for crane maintenance
New York City may boost maintenance standards for cranes operating in the city, including the addition of load cycle counters to record data regarding every lift that a crane performs.
| Dec 19, 2013
Lawmakers say EPA’s Energy Star standards lack transparency
A bipartisan group of lawmakers is raising concerns that the Environmental Protection Agency has not been transparent in drafting energy-efficiency standards under the Energy Star program.
| Dec 18, 2013
ASHRAE publishes 2013 thermal comfort standard
Major revisions for design and measurement of comfortable spaces are included in a newly published ASHRAE 2013 thermal comfort standard.
| Dec 11, 2013
Texas to require architects to be fingerprinted to get licensed
Starting January 1, 2014, architects who apply for an occupational license in Texas will have to share their fingerprints with the state.
| Dec 11, 2013
Province of Ontario is reviewing bill to require timely payments to contractors
Legislation is under review in the Province of Ontario that would mandate timely payments to contractors.
| Dec 11, 2013
Federal design-build proposal could make it easier for small businesses to land government contracts
The Design-Build Efficiency and Jobs Act, a bill pending in the U.S. House of Representatives, would streamline the bid and proposal process by requiring government agencies to use a two-step process when seeking design-build contracts for projects worth more than $750,000.
| Dec 11, 2013
NIST recommends tougher standards for tornado resilience
Buildings in tornado-prone areas should be constructed to withstand strong winds just as hurricanes are factored into building codes in coastal areas, says a federal report examining the 2011 killer tornado in Joplin, Mo.