Section 575IAC1-9-54. Metal treatment

   (a) All metal used in the construction of the bus body must be either prime commercial quality galvanized steel or aluminum, except for the following:

(1) Door handles.

(2) Grab handles.

(3) Stanchions.

(4) Interior decorate parts.

(5) Other plated parts.

  (b) All metal parts that will be painted must be prepared as follows:

(1) Chemically cleaned.

(2) Etched.

(3) Zinc-phosphate-coated.

(4) Zinc-chromed or epoxy-primed.

Particular attention must be given to lapped surfaces, welded connections of structural members, cut edges, punched or drilled hole areas in sheet metal, closed or box sections, unvented or undrained areas, and surfaces subjected to abrasion during vehicle operation.

  (c) Materials used in the construction of the bus body must not lose more than ten percent (10%) of its weight after a one thousand (1,000) hour salt spray test as provided for in the latest revision of ASTM Designation: B117 "Standard Method of Salt Spray (Fog) Testing". (State School Bus Committee; 575 IAC 1-9-54; filed Aug 15, 2014, 10:20 a.m.: 20140910-IR-575130244FRA)