Dear Dr. Gridlock:

If Metro is going to experiment with taking out the vertical poles around the doors of cars, will they please provide a place to hold on to for women of average height, or less?

Maybe they should assess the height of customers who actually use the overhead bars. I am 5 foot 6 and can't hold on to them tightly enough to hang on during sudden stops.

If the choice is between being a standing customer and blocking movement, and being a falling customer and landing on top of someone else, I (and possibly those I've landed on) think being a standing customer is the better alternative.

Janet Wamsley

Arlington

There is a good bit of anxiety about the future of the vertical poles in Metro cars, according to my mail. Here is the latest, from Lisa Farbstein, a Metro spokeswoman, who also cannot reach the overhead ceiling bars:

The next 184 Metrorail cars, known as the 6000 series, will begin arriving in the fall. The vertical poles near the doors will be gone, to discourage passengers from bunching there and blocking the way.

But the cars will have new vertical poles on the backs of the seats on the aisles. These new aisle bars will also encourage customers to stand in the aisles, not at the doors.

As for the existing cars, there are no changes involving vertical bars, Farbstein said.

I asked, why not install them down the aisles right now, if it's a good idea?

"Because the cars are designed for the bearing weight of the poles where they are now," she said.

So, rest easy, customers. More poles are coming in new cars, and none are being taken away from existing cars.

Eyes on Teen Drivers

Dear Dr. Gridlock:

I thought you'd like to know that there is a service called 1-866-Go-Get-Mom that will allow parents to monitor the driving of new teen drivers. It works this way:

Parents enroll for an annual fee, and the service sends you a bumper sticker with the phone number on it.

A witness can then call the number on the license plate to report an incident, good or bad, along with the license plate number and state. Then a voice mail is sent to your phone and/or an e-mail is sent to you.

We've had our service for about nine months and have received no calls yet, but as long as my children are on my insurance policy, they will have this bumper sticker on their car.

They fussed and fumed at first and even threatened to deface it (hasn't happened, but that would have resulted in loss of driving privileges). So far, so good.

Chris Guercio

Ellicott City

I suspect there are a lot of teen drivers cringing at the notion of being reported for bad driving behavior. And a lot of grateful parents.

For more information, call the number above or go to www.gogetmom.com. This seems to me to be a good way to help keep track of how the new drivers are doing, and it might make them more careful drivers.

Lane Laws for Hybrids

Dear Dr. Gridlock:

Are all hybrid model cars allowed to use all the HOV lanes during rush hours?

I'm thinking of buying a 2005 Honda Accord hybrid, and I'm researching this questions but can't find a definitive answer.

Richard Revzan

Rockville

Maryland makes no HOV exceptions for hybrid (gasoline plus electricity) vehicles in its Interstate 270 and Route 50 express lanes. D.C. doesn't have HOV lanes.

Virginia makes an exception for the following hybrids: the Honda Accord, Honda Civic, Honda Insight, Toyota Prius and Ford Escape. The exception means that a hybrid carrying a single occupant may legally use an HOV lane.

This exception is scheduled to expire July 1, 2006.

Online Chat

Dr. Gridlock will conduct an online chat from 1 to 2 p.m. tomorrow at www.washingtonpost.com/liveonline. .

Transportation researcher Diane Mattingly contributed to this column.

You can write to Dr. Gridlock at 1150 15th St. NW, Washington, D.C. 20071. He prefers e-mails at drgridlock@washpost.com or faxes at 703-352-3908. Include your full name, town, county and day and evening telephone numbers. Dr. Gridlock cannot take phone calls.