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
| Sep 8, 2011
OSHA issues alert on incorrectly rebuilt circuit breakers
The Occupational Safety and Health Administration (OSHA) has issued a hazard alert, warning workers and employers of certain Eaton/Cutler-Hammer molded-case circuit breakers that were incorrectly rebuilt.
| Sep 8, 2011
USGBC Streamlines LEED EB: O&M
The Council has reorganized the prerequisite and credit structure of LEED EB: O&M.
| Sep 8, 2011
USGBC: 30 Legislative ‘Wins For Green Building’ So Far In 2011
A mid-year report by the U.S. Green Building Council says that there have been “30 legislative wins for green building” across 22 states in 2011.
| Sep 8, 2011
Revised Building Codes Adopted After WTC Attacks Being Implemented
U.S. National Institute of Standards and Technology (NIST) code revision recommendations in the wake of the World Trade Center terrorist attacks are being implemented in new high-rise construction including One World Trade Center, the lead building of the new World Trade Center complex.
| Sep 8, 2011
New Sustainability Standard Addresses Disaster Resistance
To aid local governments to adopt high-performance green building codes, the Portland Cement Association (PCA) and the Institute for Business and Home Safety (IBHS) have developed High Performance Building Requirements for Sustainability 2.0.
| Sep 8, 2011
Pilot ISO 50001 Implementations Report Big Energy Savings
The International Organization for Standardization (ISO) recently published ISO 50001 to provide a recognized framework for integrating energy performance into management practices.
| Sep 8, 2011
USGBC Revises Energy Demand Response Credit
Originally launched in 2010, the revised and enhanced Demand Response Pilot Credit establishes guidelines that are anticipated to increase participation in automated energy demand response programs.
| Sep 8, 2011
Water Safety in Buildings Guide Published by World Health Organization (WHO)
This WHO book provides guidance for managing water supplies in buildings where people may drink water, use water for food preparation, wash, shower, swim or use water for other recreational activities or be exposed to aerosols produced by water-using devices, such as cooling towers.
| Sep 7, 2011
NFPA Fire & Life Safety Conference in December
Presentations on recent Fire Protection Research Foundation projects, how September 11th and the Triangle Shirtwaist Factory fire affected high rise design, and a panel discussion on emerging code issues will be featured at the National Fire Protection Association (NFPA)’s Fire & Life Safety Conference on December 12-14 in Orlando, FL.The meeting will include more than 60 educational sessions in which participants can earn continuing education units (CEUs). Presentations will be led by NFPA staff experts and technical committee members, and will be organized in four tracks – building and life safety, detection and alarm, fire suppression, and codes and standards. For more information, visit www.nfpa.org/FLSCONF.
| Sep 1, 2011
Project Aims to Automate Code Compliance Assessment
FIATECH, a consortium of owners from the industrial, power, and retail markets that build large structures, launched a project this year to validate the use of automation technology for code compliance assessment, and to accelerate the regulatory approval process using building models. Long-term objectives include the development of an extensive, open-source rule set library that is approved by industry and regulatory bodies for use by technology developers and code officials.
