By Trang Do

PHILADELPHIA (CBS) — Some Philadelphia restaurants that were hoping to increase capacity to 50%, are frustrated about the city’s new ventilation requirements. As of Tuesday, 60 restaurants have submitted applications to go to 50% capacity under Philadelphia’s stricter COVID-19 ventilation standards.

Of those, just 11 have been approved.

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Marc Wachter of Wachter Engineering decided to hold a seminar with Fishtown District to help restaurants navigate the process.

”We started looking into how realistic is this for our restauranteurs and clients to achieve and it really was a tall order in terms of hitting those standards,” he said.

The requirements include at least 20% of the air circulated by the HVAC system is from the outside. A filter system with a MERV grade of 11 or higher and 15 or more air exchanges per hour, which Wachter said is especially difficult, even for restaurants that have existing HVAC systems, as most do six to seven exchanges per hour.

“That existing HVAC system, in essence, has to be more than doubled, in order to supply that airflow,” he said.

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At the city’s Tuesday COVID-19 news conference, Health Commissioner Dr. Thomas Farley responded to the feasibility concerns and said that city officials talked to a large number of restaurants and industrial hygienists in developing the new requirements.

”We’re always interested in input, but again, our early take on this is that these are things which are doable and we want the standards to be high, we want the ventilation to be high, so that people are safe,” Farley said.

Wachter said, in addition to the price tag of the upgrades, the utility costs of running these systems so often will lead many restaurants to opt-out. He’d like to help the city modify the requirements so that they’re still safe, but more attainable.

“To look at an additional investment is only going to make it harder for [restaurants] to meet that bottom line,” he said. “So, I think a lot of them are going to stay at that 25% opening until we can look at perhaps revising that standard.”

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You can watch Wachter’s full seminar to the Fishtown District here.