Document 8Rj1jRKG2Yg5zJmO2O16dp3Yy

H. 3. Gropp 0002&O ? M. Stuapf Asbestos-Free CJL7C0 - Mt. Sinai Hospital Project December 19, 1909 The information you gave in your December 17 msu doesn't seea to add up. I don't know bow Seiikoff cannot find asbestos with an ordinary microscope but can find it with an electron microscope. The products vs furnished were asbestos-free. However, if, by error, asbestos was used, or there was sock contamination, from residual asbestos in our equip ment, asbestos would have been visible by the naked eye, or oertalnly by the ordinary microscope. There is no way for ua, or anyone, to separate asbestos to the extent that it could not be seen by the regular microscope, but could be seen through the electron microscope. There in the possibility that rtmrn the rooms In which the microscopes are, are not completely clean, and I mean by that - with sophisticated air washing equipment to wash the air - maybe they are seeing on the electron microscope fine particles of asbestos which may acme from worn automobile brake linings floating on the air. Anyway, the health authorities are now only concerned with asbestos particlss In excess of 5 microns, and are not concerned with these smaller than 5 microns. A 5 micron parties of asbestos appears to be pretty large in comparison with other materials, because a person with average eyesight can see down to about 10 niorena* in else with the naked eye. v.,. If you'd like for me to aasist you in this, or to contact Sclikoff or Harold Rosen, please advise. FKS/ec cct J. P. Verhalen R. E. Rath A. A. Bessemer /