One company — JAG Transporting Inc. of Thornwood — failed 12 out of 36 inspections and was found guilty of tampering with a security seal, exemplifying a pattern city records reveal across the industry that serves 330,000 households.

Since mid-2023, the Department of Consumer and Worker Protection has failed one in every 10 delivery trucks it inspected for faulty gauges. An analysis of ownership records shows 55% of fuel oil companies had at least one inspection failure during the past two years.

The failures affect more than 330,000 households across the city — primarily in The Bronx and Manhattan — who rely on heating oil to stay warm during winter months.

Some companies showed particularly poor records. Five Boro Fuel Oil Ltd., based on Staten Island, failed five out of nine inspections since 2023 and was found guilty on two counts of not submitting vehicles for inspection. Logic Fuel Transportation, with offices in Lake Carmel and a Bronx mailing address, failed eight out of 20 inspections and faces 11 administrative charges.

JAG Transporting Inc., based in Thornwood, failed 12 inspections — a third of its total — and was found guilty of using an uninspected pump and tampering with a security seal.

“There’s a real potential risk and a history, actually, of those devices being tampered with,” said James Hurst, a DCWP deputy commissioner. The agency considers petroleum companies among the highest risk for consumer harm.

The concerns have precedent. A decade ago, Manhattan District Attorney Cyrus R. Vance Jr. filed criminal charges against more than 45 people at nine companies in an alleged multimillion-dollar fraud scheme. The businesses allegedly shortchanged customers by manipulating measuring devices to deliver less oil than building owners paid for. Over 15 people pled guilty within a year.

Inspectors examine piping to ensure fuel isn’t diverted and verify that ticket printers accurately tell customers how much fuel they purchased. The inspection process takes 15 minutes to two hours per truck.

While failed inspections don’t always indicate deliberate tampering, they can signal problems. Measuring devices lose accuracy over time, and repairs are expensive.

DCWP conducted more than 900 inspections over two years, finding companies guilty on 56 charges. Most violations involved failing to submit vehicles for required annual inspections, though some included tampering with security seals or using uninspected trucks.

The agency said the 10% overall failure rate better represents industry compliance than individual company records.