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
Codes and Standards | Jul 8, 2022
Inefficient supply chains, outdated project delivery systems hamper construction investment
Constructing and justifying the cost of physical assets such as a manufacturing plant is much more difficult than it was decades ago, according to a report by Steffen Fuchs, senior partner with McKinsey & Company.
Building Team | Jul 7, 2022
Report explores improving architect/contractor relationship
A new study by the American Institute of Architects and the Associated General Contractors of America focuses on improving the relationship between architects and contractors.
Codes and Standards | Jun 15, 2022
Waived tariffs on solar panels expected to boost solar power
The Biden Administration recently waived tariffs on solar panels from four countries in a move advocates say will accelerate the clean energy transition and benefit national security.
Codes and Standards | Jun 14, 2022
Hospitals’ fossil fuel use trending downward, but electricity use isn’t declining as much
The 2021 Hospital Energy and Water Benchmarking Survey by Grumman|Butkus Associates found that U.S. hospitals’ use of fossil fuels is declining since the inception of the annual survey 25 years ago, but electricity use is dipping more slowly.
Codes and Standards | Jun 8, 2022
Florida Legislature passes bill requiring stricter condominium inspection
The Florida Legislature recently passed a bill to beef up building inspection requirements for many of the state’s condominiums.
Codes and Standards | Jun 7, 2022
FEMA launches National Initiative to Advance Building Codes
The U.S. Federal Emergency Management Agency (FEMA) has launched a new government-wide effort to boost national resiliency and reduce energy costs.
Codes and Standards | Jun 2, 2022
Guide helps schools find funding for buildings from federal, state government
New Buildings Institute (NBI) recently released a guide to help schools identify funding programs for facilities improvements available from federal and state government programs.
Codes and Standards | Jun 2, 2022
New design guide for hybrid steel-mass timber frames released
The American Institute of Steel Construction (AISC) has released the first-ever set of U.S. recommendations for hybrid steel frames with mass timber floors, according to a news release.
Codes and Standards | Jun 1, 2022
HKS, U. of Texas Dallas partner on brain health study
HKS and The University of Texas at Dallas’ Center for BrainHealth are conducting a six-month study to improve the way the firm’s employees work, collaborate, and innovate, both individually and as an organization, according to a news release.
Mass Timber | May 31, 2022
Tall mass timber buildings number 139 worldwide
An audit of tall mass timber buildings turned up 139 such structures around the world either complete, under construction, or proposed.
