New Deadlines for Phasing Out Fuel Oil Grade No. 4 Boilers

The maximum penalty for burning No. 4 oil after the phase-out dates has been increased to $10,000.


The maximum penalty for burning No. 4 oil after the phase-out dates has been increased to $10,000.


Mayor Adams recently signed a bill that accelerates the phasing out of oil grade No. 4 in boilers. It fast tracks the 2030 deadline for private and public buildings established by Local Law 38 in 2015. Used in buildings as a source of heat, fuel oil No. 4 the most polluting fuel oil still being used in the city. It consists of a mix of diesel oil and heavy fuel oils, the burning of which produces harmful air pollutants such as particulate matter, or soot, that can trigger asthma attacks and contribute to lung cancer, heart disease, and premature death.

With the new law, No. 4 fuel oil will be banned for use in city-owned buildings after July 1, 2025, and for all other boilers after July 1, 2027. Currently, 72 percent of buildings that use fuel oil No. 4 are located in Northern Manhattan and the Bronx.

According to Council Member James Gennaro, the bill’s sponsor, “Fuel No. 4 is the most polluting type of heating oil still being used in New York City. Annually, No. 4 heating oil adds about 120,000 pounds of lung-damaging fine particulate matter into the air. It also contains 100 times more sulfur than fuel No. 2, and sulfur oxides are among the most dangerous pollutants regulated by the Federal Clean Air Act. Removing these harmful emissions will prevent deaths, lifelong respiratory illnesses, and emergency room visits for asthma attacks every year.”

The law also specifies that no work permit, certificate of operation, or registration for a boiler to burn fuel oil grade No. 4 will be issued or renewed on or after June 30, 2024. And the minimum and maximum civil penalties for burning this prohibited fuel oil after the phase-out dates have been increased to $2,500 and $10,000, respectively.

Allowed Heating Fuels Post-2027

After 2027, only three types of heating fuel will be allowed in NYC—ultra-low sulfur No. 2 oil (ULS 2), biodiesel, and natural gas. Of course, owners can also use alternatives that don’t require burning any fuel in the building, such as installing electric heat pumps.

Ultra-low sulfur No. 2. ULS 2 is the cleanest heating oil available in the market, reducing particulate emissions by more than 95 percent when it replaces heavy oils. ULS 2 is compatible with most boilers that use No. 4 heating oil.

Biodiesel. This is a renewable fuel created from agricultural waste, used cooking oil, and other similar types of organic waste. Biodiesel users get a state tax credit in NYC, which is deductible from personal income tax or corporate tax. Conversion from No. 4 fuel oil to biodiesel isn’t as straightforward as using ULS 2, and the new system must be specially designed for it. ULS 2 and biodiesel blend is also allowed as a heating fuel in NYC, since it combines two accepted fuels.

Natural gas. This fuel is considered the cleanest fuel overall, producing even fewer emissions than ULS 2 and biodiesel. In addition, gas-fired systems have lower operation and maintenance costs. However, considering that natural gas is delivered as a utility service by pipe, while heating oil and biodiesel are delivered, the conversion from heating oil to natural gas is a more complex project than simply upgrading from No. 4 to ULS 2 oil.