For years, Peter Merriman has been concerned about viruses like the flu spreading through the air of his restaurants.

So even before the pandemic, Merriman’s restaurant in Kakaako has pumped in enough outdoor air to turn it over 24 times per hour – more air exchanges than the standard hospital operating room. 

More recently, he invested in carbon dioxide monitors and ultraviolet disinfection lights for the Oahu restaurant’s HVAC system, plus HEPA filters and carbon dioxide monitors at his Waimea location on Hawaii Island. His other two restaurants on Kauai and Maui are both open-air. 

Merriman said he ramped up the measures after reading in the news about how COVID-19 can spread through the air. 

“We don’t want to get people sick,” he said. 

Merriman’s restaurant sign ‘No Mask No service’ at the entrance area during the COVID-19 pandemic.
Merriman’s restaurant in Kakaako runs more air exchanges per hour than the typical operating room. Cory Lum/Civil Beat/2021

But when it comes to airflow, Merriman’s is the exception. Most Hawaii restaurants are not taking steps to promote ventilation and filtration, according to a Hawaii Restaurant Association board member, and they aren’t required to do so. 

City and state health guidelines don’t indicate that ventilation and filtration should be a priority. Addressing airborne transmission is framed as an option, not as an obligation or requirement. 

Experts say that’s a mistake. 

“There are thousands of superspreading events, and they are all the same thing: People in a room with poor ventilation breathing the same air, talking for a long time,” said Jose-Luis Jimenez, a chemistry professor at the University of Colorado Boulder who studies aerosols. 

“And restaurants are among the prime locations.”

Cheesecake Factory located in Waikiki during COVID-19 pandemic. Sign reads, ‘Dining Room Now Open’ during pandemic. July 10, 2020
Staying six feet apart isn’t enough to eliminate the risk of COVID-19 spread, experts say. Cory Lum/Civil Beat/2020

As Honolulu allows businesses to reopen and indoor dining returns to full capacity – allowing people to sit among strangers, unmasked, for hours at a time in an enclosed space – there needs to be a greater focus on addressing the viral threat in the air.

That’s according to a half dozen scientists interviewed for this story who are experts in the areas of epidemiology, virology, aerosols, ventilation and public health. 

While people are letting their guard down, the pandemic isn’t over, they said. Hawaii’s case counts are holding steady as vaccinations are underway, but it’s not yet clear how much protection the inoculation offers when it comes to COVID-19 variants that have already been detected on the islands. 

Hawaii should respond to COVID-19 like a person taking antibiotics, Jimenez said. Even if you’re starting to feel better, you should continue with treatment. 

Otherwise, he said, you risk the infection coming back.

Public Health Agencies Slow To Acknowledge Airborne Spread

Much has been said about social distancing to avoid viral droplets, which can be coughed or sneezed to distances up to six feet. 

But there has been less of a focus on aerosols, which float like cigarette smoke in the air and can linger for hours. 

Numerous studies suggest COVID-19 spreads this way. One early and memorable example was a choir practice in Washington that sickened dozens of people and killed two. 

A more recent study of a cluster in a Honolulu gym concluded that COVID-19 spread among people spaced more than 6 feet apart. The study, conducted by Hawaii’s Department of Health and the CDC, recommended mask use (which wasn’t required at the time of the cluster) and improved ventilation.

Mayor Rick Blangiardi flashes a shaka after the press conference announcing new COVID-19 informational banners that will installed along Kalakaua Avenue. February 11, 2021
Mayor Rick Blangiardi and other officials have promoted the need for mask-wearing and social distancing but have said little about the need to address airborne transmission. Cory Lum/Civil Beat/2021

Understanding how the virus spreads is crucial because it impacts how we address it, experts said. Social distancing, plexiglass barriers, and disinfected surfaces are not sufficient to address airborne transmission and in some cases represent “hygiene theater” more than real mitigation measures, according to experts. 

If the overall system in place is just cycling poor air over and over again, all the plexiglass in the world isn’t going to help,” said Thomas Lee, a University of Hawaii epidemiology professor. 

To combat a virus that spreads through aerosols, it’s important to ventilate – bring outside air inside – and/or filter the viral particles out of the air, experts said. 

And yet the World Health Organization and the U.S. Centers for Disease Control and Prevention have been slow to acknowledge the threat of airborne transmission of COVID-19. 

The WHO only acknowledged that COVID-19 can hang suspended in the air in July, after 239 scientists from 32 countries called on the agency to revise its guidance. The CDC didn’t address airborne transmission until October, after it posted and then deleted guidance stating that aerosols were the main mode of transmission. 

In contrast, Japan accepted the idea of airborne spread early on and made it a centerpiece of its public health message to avoid the 3 Cs: closed spaces, crowded places and close-contact settings. 

Even recently in the U.S., public health agencies still have not made airborne transmission a focus of public messaging in the way that hand-washing and social distancing have been, and scientists continue to speak out. 

Last month, 13 experts, some of whom have advised President Joe Biden, sent the president a letter calling for the immediate implementation of air standards for indoor settings like meatpacking plans and prisons. 

“It’s time to stop pussyfooting around the fact that the virus is transmitted mostly through the air,” Linsey Marr, an aerosols expert at Virginia Tech who signed the letter, told The New York Times.

“If we properly acknowledge this, and get the right recommendations and guidance into place, this is our chance to end the pandemic in the next six months … If we don’t do this, it could very well drag on.”

Dr. Sarah Kemble, the acting state epidemiologist, co-authored a recent study on a COVID-19 cluster and recommended improved ventilation. However, that advice is not easily found on DOH’s website. Eleni Avendaño/Civil Beat/2020

Jimenez believes the hesitancy to acknowledge airborne spread is based in the scientific community’s strongly held belief that germs are mainly transmitted through contaminated people and objects, not through the air. 

That concept dates back over 100 years and contributed to a culture in which the burden of proving airborne spread is akin to a prosecutor overcoming reasonable doubt in a trial, Jimenez said. 

“It’s a historical error that affects the field of public health and epidemiology,” he said. 

Throughout the pandemic, state and local agencies have followed the lead of the CDC and WHO. 

Neither the City and County of Honolulu nor the state require anything of businesses or other indoor facilities when it comes to air quality during the pandemic. 

Hawaii DOH’s webpage on “How to Prevent the Spread of COVID-19” makes no mention of airborne transmission or avoiding shared air. 

Instead, it promotes disinfection of surfaces, which might be helpful advice if COVID-19 spread primarily through contaminated objects. But it does not, according to scientific evidence. The CDC said so back in May

The Hawaii Department of Health sent Civil Beat a list of its recommendations on air quality, but Civil Beat was unable to locate that language anywhere on the internet. Asked where the information is posted, a DOH spokesman did not respond.  

Lt. Gov. Josh Green, an emergency room doctor and Hawaii’s COVID-19 medical liaison, referred questions about the lack of state standards to DOH. 

Honolulu’s makes no mention of ventilation in its guidance for specific sectors like restaurants, gyms or spiritual services. The topic is only mentioned on a general “business guidance” page that offers some “helpful tips” and links to the CDC’s website. 

Zippy’s Restaurant located near Washington Middle School.
When it comes to indoor dining, individuals have to decide whether they’re comfortable with the risk. Cory Lum/Civil Beat/2021

Civil Beat requested interviews with the Hawaii Department of Health and Mayor Rick Blangiardi’s administration to discuss why airborne transmission isn’t a greater focus of its public health messaging. Both declined to make anyone available to discuss it. 

To ensure widespread masking and social distancing, the city took a hard-line stance under Mayor Kirk Caldwell, issuing tens of thousands of criminal citations to enforce rules last year. Those rules, minus the enforcement, are still in place under Blangiardi.

But when it comes to airborne transmission, individuals are faced with deciding for themselves what is safe and what is not. 

“If a customer does not feel comfortable dining inside a restaurant, there are other available options including takeout, delivery or choosing another restaurant,” Tim Sakahara, the mayor’s communications director, said in an emailed statement. 

But without clear standards set by public health experts, the average person may not be aware of the risk they’re taking when spending time in an indoor setting, said F. DeWolfe Miller, an infectious disease epidemiologist at the University of Hawaii. 

“I can protect myself by making an informed choice about where I go and eat,” he said. “I think there still needs to be more messaging on this issue for people, so they can make an informed consent.”

‘It’s A Political Decision’ 

Meanwhile, several other jurisdictions have taken steps to address ventilation through incentives and requirements. 

Michigan has a voluntary COVID-19 Safer Dining Program. It rewards restaurants with a certificate to display to customers demonstrating that the establishment has been reviewed by an HVAC inspector and that the restaurant has implemented recommendations on air circulation.

San Francisco says businesses “must set up as much airflow as possible to be open to the public.”

San Francisco is requiring all businesses to post a checklist marking off which ventilation measures it has taken. Businesses can choose from three strategies: follow HVAC standards, get a portable air cleaner for each room or keep all windows and doors open. 

This month, Georgia’s Republican governor signed an executive order ordering restaurants and other businesses to ensure their ventilation systems are working properly

Washington state restaurants can count themselves as “outdoor” dining if they maintain levels of carbon dioxide that are comparable to outside.  

And Philadelphia won’t even let its restaurants open to 50% capacity unless they can demonstrate that their ventilation systems circulate the air at least 15 times per hour – a move that caused restaurant owners to push back. 

Sarah Nguyen, who co-owns The Pizza Press in Pearl City, said she isn’t aware of many restaurants here making efforts to increase ventilation and filtration, but she considers the existing rules about masking and distancing to be “very strict.” 

“The tables are sanitized. We have signs everywhere with ‘Stay 6 feet apart.’ No one’s allowed to come in without a mask. Our employees have masks,” said Nguyen, a member of the Hawaii Restaurant Association board. “So people are feeling more comfortable.” 

With businesses in such financial straits from the past year of closures and Hawaii’s declining case counts, Nguyen said she doesn’t see a need for additional requirements for ventilation or filtration.  

“As far as the direction (we’re going in) and opening up, that’s not a concern for me,” she said. 

But health experts say Hawaii should consider implementing some standards and requirements. Whether that actually happens comes down to how policy makers want to balance public health and economic demands, Jimenez said. 

“It’s a political decision,” he said. 

Merriman’s restaurant CO2 meter.
Merriman’s restaurant recently installed a CO2 meter. Cory Lum/Civil Beat/2021

In Jimenez’s opinion, businesses should be required to have carbon dioxide detectors, which can track how much exhaled air is in a room. Indoor spaces should stay below 700 parts per million, he said, and readings can be displayed on TVs for everyone to see with carbon dioxide levels color-coded by level of risk. The technology was used at a pop concert in Tokyo last year, according to a Japanese news report

He recommends devices that offer non-dispersive infrared sensing, which retail for $100 to $200. It’s an investment he said businesses like restaurants should be eager to embrace because they stand to lose a lot more if cases increase. 

If there is a spike in cases and restaurants “have to reduce capacity to 50%, you’re talking about much, much more money than $200 per restaurant,” he said, adding that improving air quality can help mitigate future disease outbreaks. 

“It’s not just something we should do for the next few months. It’s something we should do now and keep doing forever.” 

Multiple layers of protection help to fortify the response to the pandemic, Jimenez said, citing the Swiss cheese model of defense. Each incomplete layer of protection, when combined with other layers, improves the chances of reducing transmission. 

Other layers are wearing a tight-fitting, high-filtration mask, keeping your distance from others, limiting your time with others, and filtering the air, either with a building’s HVAC system or via portable filters.

Ventilation and filtration should be used “everywhere where we share air,” Jimenez said. That includes households where family members are going to school or work with other people during the day and returning home to family at night, he said.

L. James Lo, an expert on ventilation at Drexel University in Philadelphia, said it’s important that air quality standards be developed in a way that takes a building’s structural characteristics into consideration.

For example, a mandate requiring a certain number of air exchanges would be impossible for some buildings’ HVAC systems to meet, he said. In those cases, facilities could be required to meet the highest level of ventilation that their system allows, according to Lo, and ventilation should be done in conjunction with air filtration.

At a minimum, Lo said businesses should be required to keep their windows and doors open. 

He likes the Michigan model in which restaurants get a stamp of approval from air quality experts.

“The key thing here is to let the consumer and the general public have a very direct and very fast way to differentiate between places,” he said.

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