1940 - 1949


Many states required that each case or cartridge be marked with a percent strength. IME finalized standards for determining strength by setting a strength number for each ingredient.

The subject of sheathed permissibles was discussed for the first time.


IME worked with the Bureau of Mines to determine how to administer the Federal Explosives Act of 1917 which was reactivated upon declaration of war.

The work of the publicity committee on producing articles to promote the use of explosives virtually ceased, not to be resumed.


The Federal Explosives Act of 1917, administered by the Bureau of Mines, became effective March 17, 1942.


Since 1926, over 2.2 million pieces of literature had been distributed under the Blasting Cap Safety Program.

The Bureau of Explosives recommended to the ICC that regulations provide a method for transporting high explosives and caps in the same motor vehicle at the same time. A specification for a box to hold caps in less than case quantities was recommended. Case lots could be put in the vehicle in their original case without being in a separate box.

SLP Number 21, "Destroying Explosives" was published.


IME supported the Bureau of Mines proposal to change the limit from 1-1/2 pounds to 3 pounds of permissible explosives per hole.


The new blasting cap movie "Blasting Cap!" was released.

The Bureau of Mines required using a permissible blasting machine with permissible explosives, but since such a machine was not commercially available, waivers to this requirement were granted.

The Bureau of Mines recommended that the Federal Explosives Act of 1917 be perpetuated. The Institute opposed this recommendation.


The Bureau of Mines gave tentative approval for the use of delay electric blasting caps in coal mines.

The ICC allowed the shipment of high explosives in 23-G packaging. This packaging did not require an outer case.

In May, the office was moved to 343 Lexington Avenue (Between 39th and 40th Streets) in New York, occupying the top two floors of a five story building.


The first blasting cap display board, with four examples of blasting caps and electric blasting caps was produced.

IME participated in the investigation of the Texas City, Texas, explosion of ammonium nitrate.

The Federal Explosives Act of 1917 was canceled by President Truman.

The Bureau of Mines made the 3 pounds per hole permissible limit permanent.


Pennsylvania issued regulations limiting the amount of ground vibration in blasting.

ICC allowed fiberboard boxes for transporting electric blasting caps.


The movie "Blasting Cap!" was shown on television for the first time.

The requirement for sawdust in packages of semi-gelatin explosives was eliminated.