RICHMOND (CBS SF) — Firefighters in Richmond issued a shelter-in-place order Wednesday afternoon because of a natural gas leak and nearby residents are being asked to close their windows and turn off HVAC systems, according to a deputy fire chief.

The leak was first reported at 1:01 p.m. at the corner of Nevin Avenue and Harbour Way. The first emergency crews were on scene by 1:07 p.m.

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A 3- to 4-inch commercial gas line was ruptured, although the cause of the leak is still under investigation, according to Deputy Fire Chief Emon Usher.

Firefighters shut down a nearby post office and the Hacienda Grill at 1000 Nevin Ave. They also issued a shelter-in-place order for Kaiser Permanente Richmond Medical Center at 901 Nevin Ave. and a number of residences in the area.

Harbour Way is closed from Barrett Avenue to Macdonald Avenue and Nevin Avenue is closed from Ninth Street to 11th Street.

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There are about 20 firefighters at the scene, and they’re concerned about ignition. A safety hose line is in place to protect PG&E workers, nearby residents and buildings, according to Usher.

The wind is carrying the gas in a northeast direction, but it’s dissipating quickly, Usher said.

“Natural gas tends to dissipate whereas propane tends to sit low and be more difficult to manage,” he said. “But we certainly don’t want anyone out and about in the direction that the gas is going.”

PG&E did not immediately respond to a request for more details.

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