Air Quality Health Advisory In Effect Tuesday: State Officials Say Take Mass Transit, Set Thermostats To 78

State officials are urging Long Islanders to take mass transit and raise their thermostats ahead of a Tuesday air quality health advisory.

By Tom Gambardella, Patch Staff

May 18, 2026 5:07 pm EDT

(Patch Graphics)

LONG ISLAND, NY — The New York State Department of Environmental Conservation has issued an air quality health advisory that’ll be in effect from 11 a.m. to 11 p.m. Tuesday, warning Long Island, New York City and Hudson Valley residents of potentially dangerous levels of pollutants in the air.

According to the DEC’s announcement of the air quality advisory, officials are concerned about the level of Ozone that could be in the air on Long Island, bringing the Air Quality Index (AQI) above a value of 100. The AQI, the DEC said, was created to quantify the level of pollutants in the air with higher point values corresponding to a higher health concern.

In this case, state officials say they’re worried about “ground-level ozone,” a phenomenon that can lead to photochemical smog and is mostly caused by car exhaust and out-of-state emission sources. It is not, state officials noted, the same kind of Ozone that exists in Earth’s atmosphere.

While the gas is odorless and colorless, the DEC said elevated Ozone levels can be a concern for people with heart disease, high blood pressure or respiratory disease, as well as young children, seniors and people who work or exercise outside. Symptoms of elevated Ozone exposure, the DEC said, may include shortness of breath, chest pain or coughing.

First on the DEC’s list of recommendations for saving energy is using mass transit or carpooling whenever feasible, noting that “automobile emissions account for about 60 percent of pollution in our cities.” The DEC has also recommended that Long Islanders turn off the lights in unoccupied areas of their homes, set their thermostats to 78 degrees, close blinds and shades in their homes, limit household appliance use especially before 7 p.m., set refrigerators at more efficient temperatures, and purchase and install energy efficient lighting.

By nighttime Tuesday, the DEC said Ozone levels should decrease. The full health advisory is available here.