Washington area consumers facing the winter's high heating bills are protected against arbitrary utility cutoffs by safeguards adopted by companies and regulatory commissions, officials said yesterday.

The rules in the District of Columbia, Maryland and Virginia vary somewhat, but all basically provide that delinquent customers be given reasonable notice of the company's intention to turn off electricity or natural gas before action is taken. In addition, companies generally postpone disconnections when the weather is nasty.

But utilities can and do disconnect customers sometimes. Last year, the Virginia Power and Electric Co. (Vepco) turned off service to 70,000 customers who hadn't paid their electric bills. The Potomac Electric Power Co. (PEPCO) disconnected 14,400 delinquent customers. And the Washington Gas Light Co. (WGL) did the same to 22,745 delinquent customers.

"We try to work with customers when they can't pay, whether it is because of their health or unemployment or some other reason," said Vepco representative Rodney Smith. The company will arrange for extended payment plans or direct the customer to an organization that can help pay the bill, Smith said.

"But when we encounter a situation in which the person is adamant and simply won't pay the bill, power will be cut off . . . . We feel we have to be fair to those other customers who have paid."

As utilities became more sensitive to consumer demands and local government mandates, however, the number of cutoffs has stopped rising as rapidly and in some cases has declined.

Meantime, uncollectible accounts have been climbing for some companies. Vepco wrote off $4.4 million in uncollectibles in 1980, up from $2.7 million the previous year. The ultimate effect of such action, however, is that customers who don't pay are subsidized by those who do. This is because uncollectible accounts are rolled into the base of expenditures on which customer rates are computed.

Utility disconnections first became an important issue in the early 1970s after the sudden increase in energy prices left consumers scrambling to pay their heating bills. Utilities faced with their own escalating energy costs disconnected delinquent customers. Concern that customers might freeze to death or become ill after losing their service triggered a variety of state actions aimed at providing consumer protection.

In the Washington area, that protection is strongest in Maryland and weakest in Virginia. D.C. falls somewhere between.

What makes the Maryland rules so tough is a requirement that the utility file a written affidavit with the Public Service Commission before disconnecting a customer. The affidavit must say that the company has met all notification requirements and that disconnection won't threaten the life or the health of those inside the household.

D.C. doesn't require an affidavit. But it does have a consumer Bill of Rights that says companies can't disconnect during freezing weather or when the customer has a physician's certificate stating that disconnection would be detrimental to the health or safety of those in the household.

Virginia has no consumer bill of rights and no affidavit requirement. Instead, it has a State Corporation Commission standard saying that it has found the internal policies of the state's utility companies on disconnection to be adequate.

Essentially, those policies provide for a 10-day final written notice of the company's plans to disconnect. That final notice typically comes only after the bill has gone unpaid for two to three months.

Both WGL and Pepco also have policies against disconnecting any customer when the outside temperature is forecast for 32 degrees Fahrenheit or below during the next 24 hours or when there are medical problems, such as a new baby in the home.

Vepco doesn't have a formal policy against disconnections due to weather or medical problems. But representative Smith said he "couldn't imagine Vepco disconnecting anyone in a blizzard."