Sources familiar with the District’s plan say the D.C. fire department could make the switch to encrypt its channels as soon as next week. It means only officials and firefighters with direct access to them will be able to listen in.

The D.C. fire department is moving ahead with its plan to encrypt its radio channels. It is a decision being met with resistance by some Washington area fire chiefs who call the policy unsafe for first responders.

It is a plan that has officials in Montgomery, Arlington and Prince George’s counties deeply concerned. In fact, one department is warning it may not send mutual aid to the city if the plan goes through.

Here is the way it works. If the D.C. fire department needs additional engines and trucks to assist in emergencies — like it did when Frager’s Hardware store caught fire last year — officials request mutual aid from outside the city.

And after years of planning, communication is seamless with radios that can share communication among the District and all of the surrounding jurisdictions.

But experts are now warning the District’s plan to encrypt its fire channels could throw mutual aid into chaos.

“It really will be devastating,” said former D.C. Deputy Fire Chief Demetrios Vlassopoulos. “It will be devastating, not only to the safety of the first responders coming into the District of Columbia, but it will be devastating for the general public because our ability to coordinate with our regional partners when they come into the city will be greatly impeded.”

Vlassopoulos, now retired, has extensive knowledge of the District’s radio system.

“The risk of encrypting everything is the region does not have the proper encryption radios and they will no longer be able to seamlessly and transparently get into the incident command system,” he said.

In fact, the District’s plan is so troubling, Prince George’s County Fire Chief Marc Bashoor issued a statement on Tuesday, which reads in part: “The Council of Governments Fire Chiefs Committee requested a delay in the implementation of any encryption plan by the District of Columbia Fire/EMS Department, and has recommended alternatives to full encryption. To date, no official information or alternative plans have been communicated.”

And that is not all. Arlington Fire says the District’s plan will “compromise mutual aid communications” and Montgomery County may not send mutual aid at all.

“We have not been officially notified, but the operations chief in Montgomery County believes it would be a significant life safety issue if we have the inability to communicate with either D.C.’s dispatch or the units on the scene,” said Montgomery County Fire and Rescue spokesperson Pete Piringer. “So if we were called into the District, we would have the inability to communicate with them.”

And with D.C. Fire and EMS now short six ladder trucks after failing inspection over the weekend, mutual aid is a real possibility. All three jurisdictions have said they have been asked to help if need be.

The deputy mayor for public safety, Paul Quander, initially floated the idea after the shooting at the Navy Yard and it was met with resistance by several members of the D.C. Council — the chairman included.

On Tuesday, Phil Mendelson repeated his concerns.

“There is not a person who could possibly be listening to the channels, the public safety channels, who is going to do something contrary to the interests of Fire and EMS in putting out the fire, so I don’t know why they are encrypting,” he said. “I think it is a bad idea.”

Several years ago, also against the wishes of the D.C. council chairman, the D.C. Police Department encrypted its channels.

A spokesperson for Quander, Keith St. Clair, said the deputy mayor was not available to comment and instead sent this statement: “I have been told that the mutual aid channels that are used are unencrypted and the agencies from jurisdiction would have continue (sic) to have access to those and our dispatch even if tactical channels are encrypted.

1. FEMS would NOT move its dispatch calls to encrypted channels; they would remain available to the public and media. Only tactical channels would be encrypted.

2. That in mutual-aid situations where DC FEMS is working an incident that involves fire personnel from other jurisdictions, the tactical channels that are used are able to be heard by all the agencies involved.”

Full statement from Prince George’s County Fire and EMS Fire Chief Marc S. Bashoor:

“The Prince George’s County Fire/EMS Department is opposed, along with the National Capital Region Council of Governments Fire Chiefs Committee, to the encryption of radios without a common regional approach. The Council of Governments Fire Chiefs Committee requested a delay in the implementation of any encryption plan by the District of Columbia Fire/EMS Department, and has recommended alternatives to full encryption. To date, no official information or alternative plans have been communicated. Any plan to deliver radios to on-scene mutual-aid units, or the dispatch of extra units to facilitate face-to-face communications is a plan that falls short and creates an inherently unsafe environment for emergency responders.”

“In the years since 9-11-01, the National Capital Region has achieved the enviable position of having most public safety agencies operating on a common operating platform. In the week that we memorialize the events of 9-11-01, encryption without a common regional approach amounts to taking a step backwards in the National Capital Region interoperability, that we have previously achieved. Dispensing interoperability and reverting to a manual process of patching radio talk-groups or dispatching extra personnel to relay information, replicates the problems that were identified after the horrific attacks on 9/11/01.”