COVID-19 Employer Information for Office Buildings

May 27, 2020


Workers in office buildings may be at risk for exposure to the virus that causes coronavirus disease 2019 (COVID-19). Office building employers, building owners and managers, and building operations specialists can take steps to create a safe and healthy workplace and protect workers and clients.

hierarchy of controls

The idea behind this hierarchy is that the control methods at the top of graphic are potentially more effective and protective than those at the bottom. Following this hierarchy normally leads to the implementation of inherently safer systems, where the risk of illness or injury has been substantially reduced.

Identify where and how workers
might be exposed to COVID-19 at work.

Employers are responsible for providing a safe and healthy workplace.

Develop hazard controls using the hierarchy of controls to reduce transmission among workers. Include a combination of controls noted below.

Engineering Controls

Engineering controls are favored over administrative and personal protective equipment (PPE) for controlling existing worker exposures in the workplace because they are designed to remove the hazard at the source, before it comes in contact with the worker.

Well-designed engineering controls can be highly effective in protecting workers and will typically be independent of worker interactions to provide this high level of protection. The initial cost of engineering controls can be higher than the cost of administrative controls or PPE, but over the longer term, operating costs are frequently lower, and in some instances, can provide a cost savings in other areas of the process.

Engineering controls: Isolate workers from the hazard

Modify or adjust seats, furniture, and workstations to maintain social distancing of 6 feet between employees.
Use methods to physically separate employees in all areas of the facilities including work areas and other areas such as meeting rooms, break rooms, parking lots, entrance and exit areas, and locker rooms.
Take steps to improve ventilation in the building
Consider using portable high-efficiency particulate air (HEPA) fan/filtration systems to help enhance air cleaning (especially in higher risk areas).
Ensure exhaust fans in restroom facilities are functional and operating at full capacity when the building is occupied.

Consider using ultraviolet germicidal irradiation (UVGI) as a supplement to help inactivate the virus.


Some infectious diseases are transmitted through inhalation of airborne infectious particles, which can be disseminated through buildings by pathways that include ventilation systems. Airborne infectious disease transmission can be reduced using dilution ventilation; directional ventilation; in-room airflow regimes; room pressure differentials; personalized ventilation; and source capture ventilation, filtration, and UVGI.

ASHRAE recommends the following:

Building designers, owners, and operators should give high priority to enhancing well- designed, installed, commissioned, and maintained HVAC systems with supplemental filtration, UVGI, and, in some cases, to additional or more effective ventilation to the breathing zone. Filtration and UVGI can be applied in new buildings at moderate additional cost and can be applied quickly in existing building systems to decrease the severity of acute disease outbreaks. Indoor Air Quality Guide (ASHRAE 2009) contains information about the benefits of and techniques for accomplishing these enhancements.
New health-care facilities, including key points of entry such as emergency, admission, and waiting rooms; crowded shelters; and similar facilities should incorporate the infrastructure to quickly respond to a pandemic. Such infrastructure might include, for example, HVAC systems that separate high-risk areas; physical space and HVAC system capacity to upgrade filtration; the ability to increase ventilation even as high as 100% outdoor air; the ability to humidify air; and receptacles at the upper room and ceiling heights of at least 2.4 m (8 ft) to enable effective upper-room UVGI. Once the building is in operation, rapid availability of filter elements and upper-room UV fixtures should be arranged for rapid deployment in an emergency.
Infection control strategies should always include a bundle of multiple interventions and strategies (not just ventilation).
Upper-room and possibly other UVGI interventions or at least the ceiling heights and electrical infrastructure to quickly deploy them

For use or for any additional information or clarification,
please contact us at 1-310-684-3839 to discuss the specific application and situation.