Over the summer, a Pew Research Center poll found nearly two-thirds of US adults think climate change is a concern for their community and the federal government is not doing enough to mitigate it. Similarly, support for protecting the environment increased eight percent between 2019 and 2020, the second-largest year-over-year increase since 2015-16.
And this increased support has renewed calls to address the restaurant industry and its numerous ways of contributing to climate change and global warming. From chemicals and energy consumption to food and water waste, restaurants are notorious polluters, accounting for up to 20 percent of the total pollution in the US, according to The Green Restaurant Association.
Several jurisdictions have taken the first step by requiring their restaurants to stop selling products made from fossil fuels. Maryland recently banned foam food containers. New Jersey enacted what environmental newsgroup EcoWatch called “the most comprehensive plastic bag ban in the country.” Across the pond, local authorities in Manchester, England outlawed the use of plastic straws, stirrers, and cotton buds.
Each of these pieces of legislation means to lower the carbon footprint of local restaurants by limiting what supplies they can buy from their suppliers. However, none of them address what makes restaurant air pollution a big deal—their exhaust systems.
Restaurants cook with lots of oils and organic matter, the remnants of which are captured by exhaust systems and filtered out of the kitchen. Last winter, researchers at Carnegie Mellon University’s Center for Atmospheric Particle Studies (CAPS) found that restaurant exhaust systems are responsible for large concentrations of organic aerosol (OA) in the atmosphere. The National Academy of Sciences estimates OA contributes to approximately 4.2 million premature deaths per year.
The researchers performed their study in Pittsburgh, concentrating on neighborhoods with lots of restaurants and busy thoroughfares. This gave them the opportunity to sample collections of released OA called “plumes” from multiple sources. Using a device called an aerosol mass spectrometer to isolate plumes released by nearby restaurants, they traced seven out of ten “plumes” in their sample back to local restaurants.
“Restaurant food-cooking emissions are a major, if not the major, driver of spatial variability of organic aerosol,” Ellis Robinson, a CAPS postdoctoral researcher, said in a statement.
Spatial variability is a way scientists measure the differences between plumes in separate areas. Plumes originating in restaurant-dense regions have slightly different characteristics than those originating elsewhere, and it’s this diversity that makes OA one of the greatest pollutants restaurants emit.
Currently, restaurant exhaust systems are largely unregulated outside of cities like Los Angeles and New York. California’s Health and Safety Code requires restaurants to have ventilation “over all cooking equipment as required to effectively remove cooking odors, smoke, steam, grease, heat, and vapors.” In New York, restaurants are required to purchase a permit from the city before building their exhaust system and must follow strict building requirements governed by the city’s Mechanical Code.
Even with these restrictions, some restaurants have forgotten their exhaust systems. Instead, they’re choosing to focus on keeping customers and revenue coming in their doors. A recent report by EaterNY found that restauranteurs are scrambling and spending big money to upgrade and clean their HVAC systems before their customers return.
It’s a fair point to argue, however, restaurants that make such a calculation risk getting their customers sick when they do decide to return. A recent study by the National Institute of Health found that particulate matter in air pollutants may contribute to the spread of coronavirus. This would help explain why California and Washington were so hard hit. A recent report by MarketWatch found nearly 25 percent of residents in those states regularly breathed unhealthy air prior to the pandemic beginning.
To avoid these potential risks, restaurant owners need to pay attention to the Indoor Air Quality (IAQ) of the places they serve. IAQ can be measured with Indoor Quality Meters that measure levels of carbon monoxide, radon, and other volatile organic compounds (VOCs) in a given area. One way to improve areas with poor air quality is to use outdoor air drawn HVAC units. The outdoor air helps dilute the indoor air, thereby reducing the risk of airborne disease transmission. Companies such as Modine have a wide variety of outdoor air products.
Business owners could also replace their traditional overhead supply systems with a displacement ventilation system. Typically, displacement systems are known as “underfloor systems” because they pump outside air in at floor level, forcing old air up to the ceiling where it’s captured and recycled.
While upgrades and modifications to exhaust systems are expensive and time-consuming, many business owners are considering them a necessary cost in order to bring customers back to their restaurants.
“It’s expensive, but it’s worthwhile,” Saga’s general manager and partner Jeff Katz told EaterNY. “Our first concern is making people feel comfortable in the space so that they can think as little as possible about the global pandemic. Nothing ruins a meal like the thought of pathogens.”