The family of a teller killed during a robbery at a National Bank of Washington branch last September has filed suit in U.S. District Court here alleging that the bank did not provide adequate security devices to protect its employes.

The suit alleges that the glass and barred windows that had previously protected tellers at the branch at 301 Seventh St. NW, where the robbery occurred, had been removed during remodeling a few months before teller Zonya Grillo Durham, 36, was shot in the head after she complied with a bank robber's demand to fill his bag with money.

"If the protective devices had not been removed, the perpetrator would not have been able to lean over the bank teller's counter and shoot," the suit says. Durham was fired at twice; one bullet struck her in the middle of the forehead.

A spokeswoman for the National Bank of Washington said bank officials had not yet seen the suit and had no comment on the matter. The suit also names the United Mine Workers of America, principal stockholder in the bank, as a defendant.

The suit, filed on behalf of Durham's 14-year-old daughter Durya by Durham's mother and brother, contends that the bank violated a federal law that requires all national banks to install and maintain devices for "discouraging robberies and burglaries." It also says the bank violated a D.C. law requiring all employers to provide a work place "reasonably safe for employes."

The family is seeking $15.5 million in damages.

The suit says that the day before Durham was killed, several of the tellers at the Seventh Street branch, including Durham, "expressed deep concern" to bank officials about the lack of security devices.

The suit says that on Oct. 31, 1973, another teller was killed in the Bank of Washington's Northeast branch "under circumstances essentially identical to those leading to the death of Durham , the Northeast branch not having been equipped with protective glass or other security devices."

After that incident, bank employes petitioned its president to install bulletproof glass around the tellers' stations.

Last October, D.C. police arrested 26-year-old William Oliver Hughes Jr. and charged him first degree murder in connection with the Durham slaying. Hughes was on parole for a bank robbery conviction at the time.