Last week we wrote about government agencies’ tendencies to “flip-flop” on guidance related to preventing transmission and spread of coronavirus (“COVID-19”), and how this impacts employers’ ability to meet health and safety compliance obligations expectations and avoid regulatory liability. Underscoring these points, on Monday the U.S. Centers for Disease Control and Prevention (“CDC”) rolled out yet another massive change in its position on the transmission of COVID-19 – one that it had previously posted, then removed, and has now posted again. The onslaught of changing information continues.

While CDC maintains that “principal mode by which people are infected with SARS-CoV-2 (the virus that causes COVID-19) is through exposure to respiratory droplets carrying infectious virus,” the agency’s concept of “respiratory droplets” for the moment has evolved to include both “larger droplets” and “smaller droplets and particles.” CDC’s new guidance, updated October 5, also notes that COVID-19 spreads easily, by close contact with respiratory droplets comprised of large and small droplets as well as smaller particle-sized droplets. In a departure from its previous guidance, CDC notes that some virus particles can also be spread by airborne transmission as a result of smaller droplets and particles that may “linger in the air for minutes to hours,” and be transmitted over longer distances and timeframes (e.g., ability to infect people more than 6 feet away from the infectious person). In some circumstances,  individuals can also become infected by airborne transmission after the infectious person has already left the area.

Per CDC’s new guidance, airborne transmission of COVID-19 can occur in “special circumstances” and conditions, but airborne transmission is not thought to be an efficient mechanism to spread the disease. Circumstances in which airborne transmission of COVID-19 have been observed include within enclosed spaces in which an infected person produced respiratory droplets for an extended period of time, such as when the infected person is breathing heavily. Other circumstances in which airborne transmission has been observed include prolonged exposure in an area with poor ventilation or following expiratory exertion (e.g., exercising). In other words, CDC views airborne transmission of COVID-19 as a possibility, but sees it as an inefficient mechanism for spread of the disease. In addition, CDC views the primary mode of transmission to still be close contact with an infected person (i.e., direct contact within less than 6 feet). As a result, CDC maintains that the current preventive measures for close contact are the most effective at preventing the spread of disease, including 6-foot social distancing, frequent hand-washing, use of cloth face coverings or masks, isolating when sick, and cleaning and disinfecting frequently-touched or potentially contaminated surfaces. Yet, in spite of CDC’s continued emphasis on cleaning and disinfection measures as a preventive measure, CDC also notes that “touching surfaces is not thought to be a common way that COVID-19 spreads.” (Recall that early in the pandemic employers were encouraged to engage in rigorous supplemental cleaning and disinfecting protocols, before we learned that fomite-transmission was not common.) Although acknowledging the potential for airborne transmission, begrudgingly, CDC has also only added the directive to “avoid crowded indoor spaces and ensure indoor spaces are properly ventilated by bringing in outdoor air as much as possible.” Further, CDC stresses the importance of having effective ventilation in enclosed spaces to prevent and minimize the potential for COVID-19 transmission.

Employers should take this guidance and compare it to their current COVID-19 response plans and procedures. Most notably, the new guidance on airborne transmission has the potential to impact layout, ventilation, barrier protection, and perhaps even require employers to revisit their virtual work policies. In particular, while distancing of employees’ work-stations by six feet remains important – depending on the layout and ventilation of the workspace additional measures may be needed to reduce the potential for COVID-19 transmission. Employers should also evaluate their ventilation system and assure it follows guidance by ASHRAE (formerly known as American Society of Heating, Refrigerating and Air-Conditioning Engineers), the U.S. Environmental Protection Agency, and other professional and government organizations on ventilation and air filtration designs to help reduce risks from the virus that causes COVID-19. (Be wary, however, of snake-oil salesmen – there are many allegedly “protective” ventilation systems being sold to the unwary consumer at extremely high cost, despite providing no added value. For example, bipolar ionization is often touted as a selling point for new HVAC systems, but often the cleaning and disinfecting claims for these systems are not able to be verified through efficacy performance data. )

To be clear, the evolution of scientific understanding of this virus is inevitable and good, as epidemiologists, health professionals, and scientists work rapidly to extrapolate findings from new data. Further, public health directives are inevitably going to shift along with that understanding – also a social good. What is NOT good, however, is employers’ exposure to potential government enforcement action in an environment of rapidly shifting and in some instances conflicting guidance. As we noted last week, OSHA generally does not regulate or enforce in the area of colds, flus, and other common infectious diseases because these are predominantly issues of public health, and not exclusive to an occupational exposure or within an employer’s direct control. CDC’s latest change in guidance, which continues to clarify that COVID-19 is a highly infectious disease that is novel and still poorly understood, simply underscores why COVID-19 should be treated as a public health issue.