Attorneys for Lorton Reformatory inmates took the first step yesterday toward obtaining a court limit on the number of inmates held at the city's three Occoquan prisons.

The attorneys, in papers filed late yesterday with U.S. District Court Judge June L. Green, asked that the District be ordered to report on population capacities at the Occoquan facilities, where 14 buildings were set afire and 32 persons injured in disturbances two weeks ago.

The attorneys also asked Green to schedule a hearing to consider establishing a population ceiling at Occoquan as well as an early release program for some inmates.

The three Occoquan facilities, housing mostly medium security inmates, and Lorton's Minimum, a low-security facility for inmates within six months of becoming eligible for parole, are the only facilities in the prison system without court-imposed population caps. The city -- which admits more inmates each month than it releases -- has recently used its Occoquan facilities as a relief valve. A cap on the Occoquan facilities would leave Minimum as the only facility without limits and could pose an unprecedented crisis for the D.C. Department of Corrections.

Representing inmates at Lorton's Central and Maximum Security prisons, the attorneys said population ceilings and other court-ordered improvements at those facilities were "threatened by severe overcrowding in the Occoquan facilities."

They asked the judge to order the District to supply information about the dormitory capacities at Occoquan in preparation for seeking population ceilings there

The attorneys asked Green to order the District to submit two reports within seven days, one listing the population capacities of each dormitory at the Occoquan prisons, and the other analyzing the impact on the total corrections system population if prisoner sentences were reduced by 30, 60 and 90 days.

A hearing on the request is scheduled for today.

Alan A. Pemberton, a lawyer with Covington and Burling, which represents inmates at Central and Maximum, said the request "is the first step in a request of the court to impose a population lid on the Occoquan facilities and to implement a phased-release program in order to achieve compliance" with the proposed limits at Occoquan and the existing ceilings at Maximum and Central.

According to City Administrator Thomas M. Downs, "The immediate issue is the presentation of data, and we will have no problem presenting the data to the court" if the temporary restraining order is granted.

Downs declined to comment on what effect population ceilings at the Occoquan facilities would have on the District's prison crisis, or on whether the city had developed any plans on how it would deal with limits at the Occoquan prisons.

In the papers filed yesterday, the attorneys said, "The time has come to recognize the system-wide interdependent nature of the prison-overcrowding crisis," adding that the city is "presently unable to comply with the court's orders at Maximum and Central without further increasing dangerous overcrowding at Occoquan."

The papers state that a July 10 disturbance at Occoquan I and II, which despite their separate names are really one prison complex, "was largely the result of overcrowding," and if population increases at the facilities continue, the increases would "likely" result in "another serious disturbance."

City officials, including Mayor Marion Barry, have attributed the July 10 disturbance to media reports about a consultant's study that said overcrowding at Occoquan was "so serious that it is reasonable to expect some major disturbance in the near future."

The consultant, Kathryn Monaco, was hired by the city to study the city's prison problems under an agreement approved by Green in April that staved off the appointment of a "special master" to oversee the operations of Central facility. Two days after stories about Monaco's report appeared in the media, inmates at Occoquan set a series of fires, damaging 14 buildings and destroying at least two dormitories. Barry said the incident was a "self-fulfilling prophecy."

Attorneys for inmates, however, attributed the fires to overcrowding at the facilities, which were used by the city to house inmates for whom there was no room in the city's other prisons that have court-mandated population ceilings.

The current overcrowding crisis was sparked by U.S. District Court Judge William B. Bryant's August 1985 order setting a population ceiling of 1,694 inmates at the D.C. Jail. According to D.C. Corrections Department population count sheets, the combined population at the three Occoquan facilities before Bryant's order was about 1,275. The day before the July 10 uprising, the number of inmates at the three institutions had climbed to 1,756.

During the same period, the capacity of the institutions had risen from 1,186 to 1,366.

The Occoquan fires caused the displacement of hundreds of inmates whose dormitories were damaged or destroyed. The city transferred hundreds of inmates to other city-run prisons, and the U.S. Justice Department agreed to take 300 city inmates into federal prisons while the states of Delaware, Virginia and Maryland also accepted more than 200 D.C. inmates.

According to the papers filed yesterday, the transfers caused the population caps at Maximum and Central to be violated. The papers also state that the agreements with other states can be terminated with 30 days' notice or less, and if the inmates are returned to the city, "the effect will be a further severe worsening of the overcrowding situation."