RICHMOND, Va. — The Virginia Department of Education (DOE) last week notified the state’s 132 school districts that as many as 4,000 school buses may need retrofitting to install a safety device that prevents the parking brake from accidentally disengaging.

The device — a brake interlock — is required in Virginia on all buses with automatic transmissions purchased after March 24, 2011, when the mechanism was added to the state Board of Education's minimum specifications for school buses. On buses equipped with a brake interlock, the parking brake cannot be released without first depressing the brake pedal.

The Virginia DOE said in a press release that without the interlock, the parking brake could accidentally disengage — for example, if a student were to slip and inadvertently fall against the brake valve.

School districts in the state were alerted to the issue after the Virginia DOE tested individual buses bought after March 2011 and found that none of the vehicles was equipped with the required parking brake interlock. Dealers provided the department with estimates on the number of noncompliant buses sold to districts since the spec was approved by the state board.

"The safety of students is the department's highest priority, and the department will work with school divisions, manufacturers, and school bus dealers to make sure that all noncompliant buses are brought into full compliance with the state Board of Education's equipment specifications as quickly as possible," said Steven Staples, state superintendent of public instruction.

School districts report annually on school bus accidents to the Virginia DOE's office of support services. According to the Virginia DOE press release, the office of support services is not aware of an incident in which a student or other person was injured by a school bus that inadvertently rolled because of an accidentally disengaged parking brake.

The state DOE is surveying districts to identify all of the buses that are in need of retrofitting. Dealers and manufacturers have been directed to submit plans to the department detailing the steps that will be taken to install brake interlocks on all noncompliant buses at no expense to school districts. The retrofitting can be done in about 90 minutes by factory or dealer technicians at districts’ transportation facilities.

Also, the Virginia DOE is asking all school bus manufacturers that are doing business in the state to make sure that interlock devices have been installed and are working as specified on all new buses delivered to Virginia districts.

The state DOE created a video about the interlock issue, which can be viewed below.