Interpretation ID: 2785y
Minnesota State Patrol
District 4700-Commercial Vehicle Section
100 Stockyard Rd., Rm. 252
So. St. Paul, MN 55075
Dear Sergeant Karl:
This is in response to your letter to Marvin Shaw of my staff seeking an interpretation of Standard No. 217, Bus Window Retention and Release (49 CFR 571.217). Specifically, you asked how S5.2.3.2, which applies to school buses, would affect the installation of certain designs of "vandal locks" on school buses. I am pleased to have this opportunity to explain this safety standard for you.
Before I address your specific questions, I would like to provide some background information. Throughout this letter, I will use the term "vandal lock" to describe locking systems installed for the doors and emergency exits of school buses intended to prevent unauthorized persons from entering the school bus through those exits when the bus is unoccupied and unattended. S5.2.3.2, the relevant provision of Standard No. 217, reads as follows:
The engine starting system of a school bus shall not operate if any emergency exit is locked from either inside or outside the bus. For purposes of this requirement, "locked" means that the release mechanism cannot be activated by a person at the door without a special device such as a key or special information such as a combination.
Your first question was whether S5.2.3.2 prohibits the use of a vandal lock system that, although it must be unlocked for the bus to start, can be relocked once the bus is started. The answer is that such locks are not prohibited by Standard No. 217. I have enclosed a copy of a December 7, 1982 letter to Mr. M. B. Mathieson in which NHTSA addressed this issue. As stated in that letter, "Nothing in Standard No. 217 prohibits the installation of locking doors [on a school bus] as long as the vehicle cannot be started with the [emergency] door in the locked position." In other words, the prohibition in S5.2.3.2 focuses exclusively on whether the vehicle can be started when any emergency exit is locked. If the school bus cannot be started when an emergency exit is locked, the bus complies with S5.2.3.2, even if an emergency exit can be locked once the bus is started.
Your second question was whether S5.2.3.2 allows a vandal lock to be relocked after the vehicle is running without the use of a key or special information. The answer to this question is yes. As stated above, the prohibition in S5.2.3.2 focuses exclusively on whether the vehicle can be started when any emergency exit is locked. If the school bus cannot be started when an emergency exit is locked, the bus complies with S5.2.3.2, even if an emergency exit can be locked once the bus is started. Nothing in S5.2.3.2 requires that any locks on emergency exits be relocked only by means of a key or some special information after the vehicle is started.
I appreciate your concern about potential problems that might arise if emergency doors are locked after a school bus is started. Nevertheless, regardless of whether you believe that NHTSA intended to make or should have made some provision to prevent emergency exits on school buses from being relocked once the bus is started, it is not possible to interpret the language of S5.2.3.2 as including such a provision. Since an interpretation cannot add or delete requirements in the language of a safety standard, the only way whereby the standard could include a provision to prevent emergency exits on school buses from being relocked once the bus is started would be for this agency to undertake a rulemaking action to amend the current language of S5.2.3.2.
We are unaware of any safety need to commence such a rulemaking. We do not have any indication that there have been deaths or injuries to school bus occupants as a result of an emergency exit being relocked once the bus was started. Moreover, the potential hazards to school bus occupants absent any Standard No. 217 requirements on this subject seem minimal. School bus doors, including emergency doors, should not be locked when the bus is in operation, and we believe that, in practice, they remain unlocked when the buses are in use. It is also our understanding that the vast majority of school buses with emergency doors that can be locked in this fashion are voluntarily equipped with warning buzzers that alert the driver to the fact that the doors have been relocked.
I hope you find this information helpful. Please do not hesitate to contact David Greenburg of my staff at (202) 366-2992 if you have any further questions or would like some additional information.
Sincerely,
Paul Jackson Rice Chief Counsel
Enclosure ref:2l7 d:ll/27/90