By Guy Burdick
On July 27, AIHA (formerly the American Industrial Hygiene Association) revealed concerns about the federal COVID-19 emergency temporary standard (ETS) in a 13-page letter to the Occupational Safety and Health Administration (OSHA). AIHA urged the agency to closely examine and immediately revise the emergency rule’s provisions dealing with ventilation, physical barriers, and transmission by inhalation of SARS-CoV-2, the virus that causes COVID-19, as well as OSHA’s use of the hierarchy of controls.
The group also suggested that OSHA remove the mini-respiratory protection program provisions from the emergency rule. AIHA stated that workers are not likely to gain any level of protection from non-fit-tested respirators and argued against allowing the voluntary use of respirators outside a formal respiratory protection program under the requirements of 29 CFR §1910.134.
OSHA’s emergency rule only applies to healthcare and healthcare support services. AIHA argued the ETS does not recognize that all healthcare workers are at risk of inhalation exposure given the strong possibility for pre- or asymptomatic transmission in healthcare settings. OSHA should consider the likelihood of aerosol inhalation, as well as droplet transmission of SARS-CoV-2, in its rulemaking, according to the group.
The group questioned the inclusion of requirements for physical barriers, which do not limit aerosol inhalation and increase the turnover time needed to remove SARS-CoV-2 and other respiratory pathogens through ventilation.
Barriers may offer a potential sense of security for workers and members of the public while effectively decreasing the mixing of air in any room where they are erected, according to AIHA. The group said that airflow inside the workplace is important to optimize dilution and reduce concentrated pockets of aerosols at the source of generation, such as near an individual.
Hierarchy of controls
While the agency discussed the importance of applying the hierarchy of controls to preventing COVID-19 in the emergency rule’s preamble, the rule itself never mentions the hierarchy of controls, according to AIHA, even in the context of developing a COVID-19 prevention plan. The group argued the ETS should list and mandate
controls in the order of the hierarchy and highlight the importance of using multiple
controls—a layered approach. AIHA suggested the appropriate order of controls for aerosol transmission should be vaccination, employee health screening, patient screening, physical distancing, ventilation, and then personal protective equipment (PPE), including respiratory protection.
The group also argued that there is no need in the COVID-19 ETS for additional cleaning and disinfection requirements in healthcare settings, as cleaning and disinfection are only important for contact transmission.
AIHA also said respirators with higher protection factors, such as full-facepiece elastomeric or powered air-purifying respirators, should be required for aerosol-generating procedures. The group also expressed concerns about:
- Requiring the use of face masks only as a means of source control and only on patients or vaccinated and/or frequently tested healthcare workers and not as personal protection from aerosol inhalation for healthcare workers; and
- Acknowledging that physical distancing requirements do not take into account the distribution of infectious particles that occurs throughout a space over time or the increase in concentration that occurs both near and far from the source over time and that physical barriers are not a replacement for an inability to physically distance.
The emergency rule should not allow the use of face shields, which do not prevent aerosol inhalation, as replacements for respirators or as a solution to an inability to wear a respirator.
The group also suggested new language for testing requirements under the ETS, including:
- Vaccinated employees do not need to be tested routinely for purposes of screening (unless there was a confirmed or suspected exposure to a COVID-19 case and/or the vaccinated employees are symptomatic).
- Unvaccinated employees may be tested periodically for purposes of screening.
- Symptomatic unvaccinated employees should be tested, regardless of whether there is a known exposure.
- Unvaccinated employees should be tested after an exposure.
- Vaccinated employees should be tested after an exposure if they develop symptoms.
- Unvaccinated employees should be tested on an outbreak setting (such as 3 or more employees within a 14-day period).
- All employees should be tested if there are 20 or more employee COVID-19 cases in an exposed group within a 30-day period. The 30-day period is subject to change to a shorter time period of 15 days based on the evolving nature and virulence of COVID-19 variants.