Arlington fire officials said yesterday that the company constructing the Olmsted Building violated two county fire ordinances in a way that interfered with efforts to extinguish the spectacular blaze at the $30 million high-rise in Clarendon early yesterday.

Fire Chief Thomas M. Hawkins said an illegally parked dumpster and a water pipe that was several stories shorter than it should have been hampered firefighters in their efforts to fight the three-alarm fire that broke out on the 14th floor shortly before 1 a.m. The violations are misdemeanors that carry penalties of up to $1,000 or one year in jail.

Officials said the fire, which they estimate caused $750,000 in damages, raises new questions about the adequacy of building inspections and the limited role area fire departments have in enforcing fire codes at buildings under construction. Area fire departments perform only informal inspections of buildings and have no responsibilities for enforcement until an occupancy permit has been requested, according to area fire and inspections officials.

"I have asked for a report . . . to find out what the facts are, what our practices are of inspecting buildings during the course of construction on a countywide basis," Arlington County Board Chairman John G. Milliken said yesterday.

Fire officials said they have not yet determined the cause of the blaze. Asked whether arson is a possibility, Hawkins said, "We never rule out any cause until we've completed our investigation . . . anything could have caused it."

Spokesmen for Richmarr Construction Corp., which was building the controversial Art Deco office-commercial building at Wilson Boulevard and Highland Street, could not be reached for comment yesterday.

According to Hawkins and Assistant Fire Marshal Richard D. Mozingo, the two fire code violations delayed firefighters' access at the site and their ability to pour water on the blaze.

In the first case, they said, a dumpster was illegally parked on Highland Street, blocking firefighters' access to a groundwater pipe. Firefighters had to push the dumpster away to get access to the pipe. A tow truck was called to remove the dumpster, but was not used because it would have damaged hoses on the street, Hawkins said.

In the second case, firefighters discovered inside the building that the standpipe, a vertical pipe that supplies water to a building's upper floors, did not reach the floor it should have. This forced firefighters to carry hundreds of feet of hoses by hand up the stairwell to reach the fire, they said.

Matt Wilkins, a county building inspector, said that under county building codes, the pipe must reach at least the floor beneath active construction work. Because workers were on the 13th floor Wednesday, preparing to pour concrete for the 14th floor, the pipe "should have been through the 13th floor; they're required to bring it up as they go."

Wilkins said the county's building inspections department -- not the fire department -- is responsible for enforcing code compliance for buildings under construction. The inspections department is looking into when the last inspection took place, Wilkins said. Normally, he said, an inspection is done when concrete is poured for a floor, so an inspector would have been scheduled to be on the site yesterday, when the 14th floor was to be poured.

Hawkins said he would like the fire department to be given more responsibility for inspecting buildings under construction. "We need to have greater responsibility in the new construction area," he said. "The issue is how frequently we inspect and how well the code is enforced."

Guy Martin, the building's project manager for the Clarendon Metro Limited Partnership, the Olmsted Building's owner, said there was very little structural damage done to the 198-foot, polished red and pink granite building. He said he expects work to resume in a few weeks, and the building to be ready for occupancy in November.