New, more relaxed rules on crowd sizes go into effect on Friday in Pennsylvania, with the caveat that these restrictions might be tightened if case investigation shows that events or gatherings are becoming a source of increased outbreaks.
Gov. Tom Wolf called it, "a gradual adjustment to our lives as we learn how we can do things safely until we have a [COVID-19] cure, or an effective [coronavirus] vaccine is widely available."
Instead of a one-size-fits-all approach that limits indoor gatherings to 25 people and outdoor events to 250, the new system is a sliding scale.
At smaller indoor venues, gatherings can be up to 20 percent of the space's capacity. That drops to 15 percent for venues with occupancies of 2,000 to 10,000 people, and 10 percent for venues with capacities exceeding 10,000.
Outdoor gatherings follow a similar rubric, but allow for higher occupancy limits.
Dr. Tom Walsh, an infectious disease physician at Allegheny Health Network, says the new rules are a more nuanced approach, since different spaces present different levels of risk to the coronavirus.
“A massive indoor space with fantastic ventilation isn’t going to be the same as a small boardroom in a hospital,” he said. “Even when you’re talking about outdoor gatherings, things like a massive football stadium is going to be different than the number of people in a pavilion in a park.”
Any time a person leaves home, they chance an exposure. But masks, physical distancing and adequately ventilated spaces all reduce risk.
Matt Ferrari, an epidemiologist at Penn State, agrees with Walsh that factors like crowd density, ventilation and activity must also be taken into consideration when accessing risk.
“These numbers would suggest that you could put thousands in a large outdoor stadium, but you would still need to figure out how to get them in and out safely,” he said. “Facilities managers and event promoters need to consider the whole event…to minimize risks at every step along the way.”
Additionally, Ferrari thinks that allowing for larger, but less risky events might cut down on smaller, higher risk gatherings, like house parties.
“People want to watch sports, people want to see each other. These things are deeply ingrained in many of our communities. Prohibiting them altogether, it drives those activities underground and drives those activities into settings [and] behaviors that might be more risky overall,” he said. “I think that's something that we really need to be cautious about, especially when we're setting really hard limits and restrictive policies.”
However, it probably makes sense to not be too lenient with gatherings.
“It you're driving down the road and the speed limit is 65, you're probably going to be going 75. And so when they plan speed limits, they actually plan that. I would say the same thing with these gatherings,” said David Dausey, an epidemiologist and the vice president of academic affairs at Duquesne University.
The more people present in any location, the more likely is that someone there has the virus.