For neighborhood restaurant owners like Erin Wallace, it won't be easy meeting those requirements.
"I took a look at it today and I'm not an HVAC person. So we're definitely going to have to bring somebody in," said Wallace, who owns the Devil's Den in South Philadelphia. In fact, she closed her restaurant for the winter.
"I have this beautiful fireplace we never even used this year. This year it really became a time where you're looking at how do you lose the least amount of money? So being closed, you lose the least amount of money," Wallace said.
She says it's great indoor dining in the city can go to 50% capacity on Friday, but the new requirements for proper ventilation are confusing, to put it mildly. Wallace showed us the health department's new spreadsheet to calculate things. It gives her anxiety. The requirements could also mean costly upgrades that may go unused.
"Just because we do this does not guarantee we can stay open at 50% because they did say if rates change and things change, they could take away indoor dining again," she said.
WATCH: Philly officials talk about new guidance for restaurants, indoor dining
In fact, several members of the Restaurant Advisory Committee released a statement Tuesday saying, "The regulations punish small, owner-operated restaurants that give Philadelphia its authentic character and support our communities of color and immigrant communities."
On Tuesday evening we also spoke with Barry Gutin who owns Cuba Libre in Old City. He says they've spent a lot of money to kill any bacteria in the air inside.
"We put in airstream disinfection which uses UVC lighting to kill the virus and any other bacteria right in the ductwork. But even at 50%, it's tough to make a living. Actually, you lose money, but we lose less," said Gutin, who will be rushing to open at 50% by Friday.
"We've never had a guest say they've gotten COVID-19 from our restaurant," added Gutin.
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According to officials, if restaurants have an HVAC system or standalone ventilation unit in use, the following standards are required to open to 50% capacity:
- HVAC system is fully operational and ventilates the entire indoor dining area
- At least 20 percent outside is air circulated by the HVAC system
- Filtration MERV 11 or higher
- At least 15 air exchanges per hour are measured indoors
- Exhaust vent has a minimum six-foot clearance from tables, chairs, or other items
- If restaurants use window fans instead of an HVAC system, at least 15 air exchanges per hour must be measured indoors
Philadelphia Health Commissioner Dr. Thomas Farley said businesses must submit documentation certifying their establishments to meet the standards from their HVAC maintenance company or the establishment proprietor.
"I should note here that we are breaking new ground, and we're not aware of other locations that have done this, but we do think this is a way to try to have restaurants get back on their feet, economically, to provide service to customers, but while also doing it safely," Farley said.