The letter about the car that broke down on the Beltway and whose driver was apparently unnoticed for over an hour {Letters to the Weekly, July 30} inspired us to offer a solution to this problem.

We call our idea "degree-of-need indicators," and they would work as follows: Each vehicle would be equipped with three colored flags (red, yellow and green) and an inexpensive wire hanger, which would hook over the window or could be bent to fit any accessible place on any type of vehicle. The appropriate flag would signal to drivers the following situations:

RED, STOP -- emergency help needed. This would be generally for medical emergencies.

YELLOW -- non-emergency help needed. This would indicate vehicle or minor medical problems.

GREEN, GO BY -- no help is needed.

Anybody who pulls a vehicle to the side of the road, or one unfortunately stranded in the middle of the road, could simply attach the paper flag to the wire, roll down a window part-way, hook the wire over and roll the window back up. Passers-by would have the option of stopping to help or calling the appropriate authorities. But at least they would know whether help was urgently needed. This system would also aid the law-enforcement agencies -- a green flag, for example, would save them an unnecessary stop.

One story that stays in our minds was the case of a man in the Chicago area who died because of a lack of aid. He was driving his car on one an expressway one morning and pulled over because he was ill. He had a heart attack but survived throughout most of the day. He was dead by the time a police car stopped at night. He had been able enough to vomit into a towel and keep the car neat, but was apparently unable to get out of the car. He probably could have hung out a flag. We can't help wondering if this might have saved his life.