WE WHO expressed more than moderate alarm at the D.C. government's elaborately hideous 911 emergency phone system when it was officially "enhanced" last year now find that apparently that army of telephonic gremlins and tape-recorded voices has crossed the Potomac and infiltrated the network in Fairfax County. The stories from residents who have called for help are painfully familiar:

A Herndon resident reported that she dialed 911 last week when she felt severe chest pains but "no one answered the phone." After two unsuccessful attempts, she gave up and dialed the operator, who did get help to the scene quickly. Rescue workers told her that about 10 other people had reported 911 problems, she said.

Another county resident said he tried to report what seemed to be a stolen car. After trying the McLean district police station, which gave him a phone number that got him a recording, he tried 911, which rang for a while and then "simply went dead." That happened twice.

Nursing home officials said they couldn't reach the emergency center on one line but did finally get through on another.

Fairfax officials insist that it is too soon to judge what is a highly sophisticated system (now where have we heard that before?) and explain that staff adjustments have been made to cut down response times. Eventually, say these officials, if all goes according to plan, residents will enjoy a technological marvel of awesome capabilities. But these inexcusable troubles don't stop at the phone dials. The dispatching system has been intolerably slow in enough instances to prompt complaints -- another familiar story.

Very little in this world is perfect, but whether it's in the District, Fairfax or the cold heart of the Yukon, emergency rescue services should never be plopped into place in this fashion, with no public warning, no efficient backup system, no reassuring live voice -- and no quick response. One mistake is one too many. Wherever 911 is the number, it should never turn into a "don't-call-us-we'll-call-you" or "this-is-a-recording" game. An emergency is just that, and Fairfax officials should get on this case -- and stay on it until they get it right.