After months of sometimes bitter feuding, the Arlington County Fire Department and the Arlington County Professional Firefighters Association have reached a compromise on what length firemen will be permitted to wear their hair.

The new regulations, which will go into effect Feb. 13, allow firefighters to grow their hair midway down their ears and to allow it to touch the back of the collar. Moustaches may extend to the midpoint between the lower lip and the chin but sideburns cannot be bushy or interfere with the seal of the helmets they must wear when fighting fires.

Mark Penn, an Arlington firefighter who was a member of the committee that negotiated the agreement, said the firemen had a accomplished their aim of achieving some freedom of expression in hair style while staying "within the safety regulations that we do recognize are there."

Penn estimated that 95 per cent of Arlington firefighters are already in compliance with the new rules. Under previous orders issued by Arlington Fire Chief Robert F. Groshon, the hair could not touch the ear and could not touch the back of the collar. Moustaches had to stop at the corner of the mouth.

The regulations caused a great deal of discontent among the firefighters, many of whom complained that Chief Groshon was trying to impose his personal grooming standards on them. The Chief has argued that the regulations are necessary as a safety measure.