Document Rj6oxdj5wYEp4gXNadMeMNBBa

experience hat shown that such practice is unwarranted. I In Brakeblok, compounds of lead formate, oxide, are used as powders in various formulae. and sulphide In Ramapo Chicago there Is a brass casting machining operation capable of producing an exposure to lead dust. i l In American Forge, lead tempering baths are used in the die sinking department. Lead dross from .these baths could be a hazard. Manganese - &isco and National Bearing affected. Acute Intoxication is almost unknown and chronic poisoning, a very disabling and serious condition, is rather Infrequent industry-wide. Well established cases fail to respond to treatment. In founding, manganese is usually associated with the production of manganese steel castings and manganese bronze. The maximal allowable concentration Is 6.0 milligram per cubic meter of air. This value is seldom exceeded in the foundry industry even in the case where no exhaust ventilation is; provided* Noise - AH divisions sire concerned. Occupational loss of hearing from industrial noise is now recognized as 'a definite disease entity and is already compensable in some States. There are insufficient data available in the field to es tablished noisle levels in the various frequencies or octave bands above which impairmept of hearing will result. To make the problem more complicated. It Is difficult if not iupossible to distinguish the amount of loss of hearing due to presbycou- sis and that due to acoustical trauma. I Sound measurements made in typical foundries show noise levels in excess of 100 decibels even in the frequency wave lengths from 2000 cycles per second and tip. While there is no conclusive proof that this type of exposure is harmful, many investigators are of the opinion that it is. I Measurements already made, show that tumbling mills, shake outs, grinding and chipping jobs, electric arc furnaces, air cylinders, and gas fired ladle heaters and furnaces are the principal sources of noise In the foundry. ; pre-employment audiograms will measure a job applicant's bearing threshold. Periodic audiograms will show whether there is any loss of hearing taking iplane. The amount of loss due to oncoming old age and that -- --^.wyatjlon would need to be evaluated by an otologist.' * Prevention and control of industrial noise is difficult and the services of an engineer who has specialized in the problem is usually necessary in opder to obtain an attenuation worth the cost involved. i Resins - Brakeblok, Electro Alloys, and National Bearing. 30 I SPNY 000160