Five D. C. firemen were overcome by fumes emitted by polyvinylchloride insulation on electrical equipment while fighting a fire that was caused by arson Sunday night at the John Kilpen-Hotel, fire officials said.

Officials said Clyde Dowthot, owner of the 90-rooms hotel at 2310 Ashmead Pl. N. W., and Edward Proudfoot, a room clerk, were treated for smoke inhalation at the Washington Hospital Center and released.

No other injuries were reported. Fire officials said the fire, discovered about 8:15 p.m. was the second at the hotel in 24 hours. They said both were caused by arson. Damage was reported minor.

Fire officials said those foremen who were overcome had removed their breathing masks to carry out debris after the fire had been extinguished.

Fire officials said that they are developing equipment that would warn firefighters of the presence of dangerous fumes.

Deputy Chief John Breen said a badge that changes colors in the presence of the fumes is being tested. Breen said the warning badge has not yet reached the production stage.

The firemen who were overcome were identified as Lt. Robert Soper, of Engine Co. No 1; Sgt. William Sturgill, Engine Co. No. 9 and Fire-fighters John Gruver and John Goldsmith both of Truck Co. 9 and Charles Drumming, of Engine Co. No. 1.

All were reported in satisfactory condition yesterday at the Washington Hospital Center.