Section 575IAC1-9-18. Construction

   (a) The bus body must be constructed to withstand an intrusion force equal to:

(1) the curb weight of the vehicle; or

(2) twenty thousand (20,000) pounds;

whichever is less. Each vehicle must be capable of meeting this requirement when tested in accordance with the procedures set forth in subsection (b). The complete body structure, or a representative seven-body section mockup with seats installed, must be load tested at a location twenty-four (24) inches, plus or minus two (2) inches, above the floor line with a maximum ten (10) inch diameter cylinder, forty-eight (48) inches long, mounted in a horizontal plane.

  (b) The cylinder must be placed as close as practical to the midpoint of the tested structure, spanning two (2) internal vertical structural members. The cylinder must be statically loaded to the required force of curb weight or twenty thousand (20,000) pounds, whichever is less, in a horizontal plane with the load applied from the exterior toward the interior of the test structure. When the minimum load has been applied, the penetration of the loading cylinder into the passenger compartment must not exceed ten (10) inches from its original point of contact. There may be no separation of lapped panels or construction joints. Punctures, tears, or breaks in the external panels are acceptable but are not permitted on any adjacent interior panel. Body companies must certify compliance with this intrusion requirement and include test results, as requested.

  (c) The body construction must be reasonably dustproof and watertight.

  (d) The bus body must be securely attached to the chassis. (State School Bus Committee; 575 IAC 1-9-18; filed Aug 15, 2014, 10:20 a.m.: 20140910-IR-575130244FRA)