For this reason, Army regulation 385-10 prohibits the wearing of headphones while walking, running or riding a bike on post. And it’s not just the Army. The activity is also prohibited by Virginia State Code 46.2-1078 and 32 Code of Federal Regulation 634.25, said Lt. Ronald Foster, the traffic division chief for the Joint Base Myer-Henderson Hall Police Department.

The fine for use of ‘‘distractionary devices” under the CFR is $80, said Foster. He said this also applies to drivers wearing headphones inside vehicles as well as pedestrians and motorists who use earphones for cell phones, personal digital assistants and similar devices.

‘‘Using them in one ear is O.K.,” he said. ‘‘Two is a no-go.”

Foster said the $80 fine has not always been imposed but that it will be issued more frequently as a deterrent if incidents continue to rise.

Officer Stephen Brant of the JBM-HH Police Department recalls that a pedestrian wearing headphones was hit by a car on Fort McNair two years ago.

More and more people are using the technology, said Jacqueline Gandy, a safety specialist with the JBM-HH Safety Office. The problem, she said, is that ‘‘You can’t hear train whistles or vicious dogs coming up behind you.”

Mary Thomas, a safety office occupational hygienist who returned from a temporary duty assignment in Iraq six months ago, said even deployed Soldiers over there sometimes unwisely used headphones while exercising.

They couldn’t hear the whistling of rockets or the C-RAM alert system to warn them they were in danger, she said. ‘‘It limits your situational awareness.”

Foster said he anticipates more infractions as the weather gets warmer and winter turns into spring.

He said senior leaders have even been stopped on post for ignoring the regulation. It’s important that they be notified because they set an example for others, he said.

For more information about headphone use on post contact the Safety Office at (703) 696-6996.