Somehow, the tetraethyl tin became tetraethyl lead and ^joth it and naphthylamine became con verted to carcinogenic agents.

Ttrtlar Secretary Lead Industries Association, Inc.

Or write National Lead Company, Floating Floors, I nc., Room 4612,111 Broadway, New York, N.Y. 10006.

LEAD INDUSTRIES ASSOCIATION, In c . 292 MADISON AVENUE NEW YORK.

MEMORANDUM TO: /Dr J Dr Dr Dr Dr Dr Mr Roy C.

Bardswick and J. to matiFilion their most recent report for Filion of asbestos cliff of his port In general the technique is satisfactory as a means of comparison between respirators although it differs from the standard bureau of Mines certification procedure in flow rate particulat con- centration and other factors including the use of asbestos rather than silica dust A secondary part of the procedure was the evaluation of leakage around the mask using a helium concentration technique There is some question concerning the significance of these helium leakaye tests rubber Mark & especially where the face seal is accomplished by a sponge run media Filter penetration tests were using respirator operating at a total air volume of a Burd liters minute and with fiber concentrations of approximately 20 100 fibers respectively The data indicate that the new 3M disposable filter the Weisch disposable filter and the Willson prototype filter were all sat~-l- factory from a penetration standpoint From u face leakage stand- stand- point the 3M and Welsch units were satisfactory but the Willson prototype showed excessive leakage This will undoubtedly be less with the softer plastic to be used in the final material By combining the fiber penetration through leakage with the fiber penetration through the filter media it was possible to calculate an anticipated fiber concentration within the mask for each of the three concentrations used in the test While this calculation again appears an approximation at best it would reveal the suit- ability of the Welsch and 3M masks for most applications A sig nificant problem was revealed in that at the lower fiber concan- trations 20 fibers the mask efficiency was markedly reduced leading in some cases to a greater fiber Joncentration within the mask in an atmosphere of 23 fibers than i.. a concentration of MEMO FOR VISIT TO FILE MCGILL UNIVERSITY 100 fibers when the entire test rid This problem must undoubtedly be exar me: NIOSH and OSHA present their proposals .n impreted respirator control respirator of r was considered in more detail when the near futar. cr The report also attempted to arrive at an index of effective- effective- ness by combining the three factors of filter media +2 iiency face leakage and inhalation resistance In this ase . .in the Wels its appeared to were stisfactory From be the a cost best although standpoint the th Mposables Mposables Mposables M uni will > undoubtsdly be most acceptable since that will proi 50 to 5 per cent as much as the Welsch disposable aun.c.

The lead problems of industry, in relation to their own employees and also to the public, were subsidized by a group of industrial organizations involving the lead trades.

If that falls through, I now have another lead.

Pigments Since last report, lead-free Zinc Oxide wa3 reduced $.02 lb. and leaded grades $.01$ lb.

Joseph Lead Co. get lead poisoning and' :A'Vt CV . f - ' -HCav1 .

Thin sec tions of approximately 60 mg were stained with uranyl acetate12 and lead nitrate or Millonig's lead13 alone.

P.xamples are lead oxide fume from smelting and iron oxide fume from are welding.

(2) More serious errors are the statements concerning lead in the Malcolm H.

DRAFT MINUTES - ' *' * JOINT MEETING OF EXECUTIVE COMMITTEES ZINC INSTITUTE, INC. and LEAD INDUSTRIES ASSOCIATION Union League Club, Mew York July 10, By direction of the President and in accordance with the By-Laws of Zinc Institute, Inc., and Lead Industries Association, a meeting of the Executive Com mittees was held on July 10, 1969.

Podesta be authorized to sign and submit the bid or proposal of 4,000# Lead Alloy Ingot for the following project Req.