Waymo has changed a company policy that had employees refueling the company's self-driving minivans with the engine running following a whistleblower letter sent to fire officials, The Arizona Republic has learned.

A person identified only as "a concerned Waymo driver" sent an email last week to the Chandler Fire Department reporting that employees were instructed to refuel Waymo's Chrysler Pacifica hybrid minivans with the engines running.

Initially, the fire department responded by telling the letter-writer that the issue needed to be raised with Waymo's safety department.

But after The Republic contacted Waymo and the fire department this week, the company said it was immediately changing its policy.

Waymo officials did not dispute the content of the whistleblower letter, and would not respond to specific questions regarding why that policy was in place.

“We have changed our refueling practices," the statement said. "We pride ourselves on having a strong safety culture, and we work hard to hold ourselves accountable to the community, public safety, and every member of the Waymo team in order to live up to our mission of improving road safety for all.”

Vans' owner manuals: shut engines off

Experts have debated the actual dangers of refueling vehicles with the engine running for years, with many people reporting they keep the engine on for a variety of reasons, including to keep the air-conditioning or heater running.

But shutting off the engine remains standard advice, including in the owners' manual for the Chrysler vans Waymo uses for its self-driving operations in Arizona, and on gas pumps.

The City of Chandler operates under the 2015 edition of International Fire Codes. Those codes state that where gasoline is being dispensed "the engines of vehicles being fueled shall be shut off during fueling," in addition "smoking and open flames shall be prohibited."

The whistleblower responded last week to the first message from the fire department by stating that the city of Chandler should be responsible for enforcing fire codes. The fire department responded that it needed more information about when and where violations occurred.

The whistleblower responded that all Waymo vehicles were refueled this way, most frequently at a site at 56th Street and Chandler Boulevard.

A second response after inquiry

The whistleblower received a different response following an inquiry from The Republic.

"The Chandler Fire Marshal had a conference call with Waymo management and informed them of the situation," the fire department wrote to the whistleblower on Wednesday. "We were informed today that Waymo will be making policy changes immediately."

The letter continued: "Thank you for helping make Chandler a safe place to live and work by bringing this information forward."

The department sent a separate response to The Republic.

"As we have seen over the last two years, Waymo responded immediately and took prompt action to review their procedures," Battalion Chief Jeff West wrote. "We could not be happier to have this type of relationship with a company that wants to develop a new technology and new service in the city of Chandler."

Reach reporter Ryan Randazzo at ryan.randazzo@arizonarepublic.com or 602-444-4331. Follow him on Twitter @UtilityReporter.

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