Dave Parker wrote:
"The second grab iron was indeed approved by the ARA (not the AAR, which was formed in 1934) at their annual meeting in June of 1932. It is murky as to the effective date, in part because, at least as described in the Proceedings, it seems to be a recommendation rather than a requirement. That may have changed later on. I see no reference to any ARA rule number in the 1932 Proceedings."
1931 Recommendation from the Committee on Safety Appliances approved (via letter ballot, Circular D.V. 760, April 1, 1932). Membership approval (over 2/3 majority as required) was announced within Circular D.V. 786, June 1, 1932, and subsequently added to the 1933 A.R.A. annual revision of The Interchange Rules issued January 1, 1933.
Rule 3, Section S, Paragraph 2:
"Safety Appliances: Additional grab iron on side of car at end opposite side ladder, in accordance with A.R.A. Standard location, required on all house cars, hopper cars and high side gondola cars built new or rebuilt on or after August 1, 1933.
Note: It is recommended that when house cars, hopper cars and high side gondola cars, built new or rebuilt prior to August 1, 1933, receive Class I general repairs, additional grab irons as specified above be applied."
The rule remained the same (thru 1960) except for the change from A.R.A to A.A.R, effective October 12, 1934.
A.R.A. Standard for the location of the bottom grab was 58-1/2" from the top of the rail, but not a requirement. Dave's other listed specifications are spot on.