One of the benefits of hybrid vehicles is that they can often coast along on electric-power alone with the only sound emanating from the vehicle being a quiet whirr from its electric motor or a rustle from its tires, both of which are easily drowned out by ambient street sounds. Though this might be great for noise pollution, it poses a threat on blind and elderly pedestrians who rely on the sound of an engine to determine whether it’s safe to cross a street.

Lawmakers in the U.S. have now heeded calls from pedestrian groups and plan to introduce a new bill in Congress tomorrow that will require the Transportation Department to establish safety standards for hybrids and other quiet vehicles, including an audible means for alerting people that cars are nearby.

Backing the legislation is Baltimore-based National Federation of the Blind, although the group admits that it’s unaware of any cases of a blind person being struck by a car they couldn’t here, reports the Associated Press.

Any changes are likely to be several years away at the earliest as the new bill also requires the Transportation Department to conduct a two-year study before issuing any safety standards. Carmakers then have a further two years to comply with the new changes.

Some of the proposed solutions include placing speakers that constantly play the sound of an engine in hybrid cars. Sadly, we can see this becoming just the latest gimmick for individuals who want to make their ordinary cars stand out.