Document GKXDZOB58m3Q6Ovey7aRnbkpY

Monsanto Chemical Compan^ 5* BwhI^S*r * Rb Washington, D. 0* WASHINGTON, D. C. ft. I ft. 0.& 1*0001nfeld . Kelly Juno 12, 1936 Mr* R b HsttOfl M. 0 Pydu&ul 130 1 have dlsousaed the calculation of parts per million with Mickey Alport of BuShips today. They uee a method referred to In the Industrial Hygeno and Toxicology Magazine titled "Patty.w Reference is page 132, Vol. 1. This is the simplest method and they olaim it gives the same answer ae the longer approach. Parts per million concentration la obtained by di viding the partial pressure of the material by the total barmetrio pressure and multiplying by 1 million* In the oaee of Aroolor 1242 they divided the partial pressure of *001 am Rg by 760 mm Hg and multiplied by 1 million add obtained approxi mately 1.3 parts per million. This is how they feel Trion maxes reference to .2 parts per million being equivalent to 13 to 20jt maturated vapor. In the oase of Pydraul 150 Alpert feels that the parts per million would be equal to l.j> multiplied by the nolo fraction of Aroolor 1242. If this is true, we are nearer to being acceptable to the Wavy but their toxicity limit of *2 parts per million would he approximately $0 of the saturated vapor pressure at 00* f. The information they want la as Dr. Kelly pointed out in his memo of June 7* Should their atone ethanol amine air aorubblng system help at all, we might be in good shape. ' ' a* Robert Sldo / DSW 162470 STLCOPCB4041043