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ccaoiEBYs m m m s o u xm of h a d f j po s u?y iw COHHECTIO WITH THE BPAIi OF A GASOLINE ?".'0 AGE i*<2s 0-i TAlgOF COHTIHTBTAL OIL COMPAHY, AT AT TE.SIA . HEW > MEXICO i1 The clinical information on these cases of load poisoning <o vas such os to Indicate at the outset that the exposure bad been *3 very severe *\;ihe tsan vho died worked for less than a day before 13 1 he became acuteljy ill. Apparently hia Illness developed steadily ^ in severity until his death. This could only have occurred as the 1 ^ result of gr-oss contact of the skin with tetraethyl lead, or as ; 'H'tt ; "I r the result of the inhalation of high concentrations of tetraethyl 4* H | lead vapor in tho air.J The latter, no doubt, represented the true rVr> X situation. Additional infcraation on the men indicated that they had been exposed! sasevhat to triothyl lead compounds. This, how * _ever, need not have been severe, and under the conditions that are i 4 known to have existed, It could not have been a significant factor * ^ in tho induction of cases of poisoning. AA 4j The severity of the lead exposure has boon confirmed by A a 4 the analytical data obtained on the urine and blood of several of =>-4 the exposed non. These data are attached hereto, without additional * cctsnsent. i41. -i The aotirce of the exposure is evident from the analytical results on the sludge, the scale, and the cloth that vas placed over 1 tho only opening in the tank during a period of aeration. These -o rr"also are attached* -i,J The organic lead content of the sludge was high, - much 4^ ^ h i g h e r , in fact than such sludges generally are. Furthermore the S. larger proportion of the organic lead in the sludge vas tetraethyl lead. Whether this vaa there aa tetraethyl lead prior to the pro longed steasing of the tank cannot he ascertained, hut there are at least tvo possibilities. This tank vas a blending tank at one time, (a) It may. have had Ethyl Fluid introduced into it in such : a manner that the latter settled to the bottom of the tank and then later seeped through into the space beneath the tank, (b) Or there may have been a considerable mount of organic lead salts in the sludge s and these may have been converted in part to tetraethyl lead by the steaming process* In any case tetraethyl lead vas there and this vas vaporized into the air by the steam and partly removed from the tank and partly deposited on the vails of the tank . by condensation. In no other vay is it possible to explain the presence of tetraethyl lead in appreciable concentration in the sample of scale removed from the vails of this tank, (cf. the tetra ethyl lead content of the scale). The result on the soil sample taken from beneath the tank .. is of no value in the reconstruction of the conditions within the tank, since the organic lead content vas too low to have specific significance. . . - ' ' The significance of the results on the piece of cloth is fairly clear, despite the fact that the character of the lead com pound deposited ih the fabric vaa not determined. Probably moat of the lead in the air that passed through the cloth failed to be trapped by the cloth* Certainly this vas the case if this lead vas in the fora of vaporised tetraethyl lead. At all events the presence of lead in apprciable concentration in the air escaping from the tank has been demaonstrated. K F 0021400 3. the workmen canot be determined with precision. However, it cannot be said that there are an; nt-v or hitherto unanticipated factera that need to be taken into account to explain this case. It was merely one of the series of extraordinarily dangerous tanks that has case to our attention. It is precisely this set of conditions that the tank-cleaning regulations are designed to deal with. (The application of these regulations did protect the cleaning personnel in this case*} Our. safety personnel must accept the fact that such conditions are destined to occur from time to time* and that gaso line storage tanks in general must be dealt vith on the assumption that such conditions may be encountered without warning or fore knowledge thereof. Despite the proved efficacy of the present regulations, if followed, in warding off danger under the conditions that existed in this tank, this incident may be regarded as on indication of the need for a device that may warn safety engineers of the existence of high ' concentrations of tetraethyl lead vapor in the air within tanks. Every effort will bo mode to develop such a device. Certain ideas have been advanced in this'direction and will be explored. However, it seems inadvisable at this time to acquaint field safety personnel with this possibility, since to do so might suggest that there is a technical Inadequacy in our present procedure, and that no human fault could be blamed for this episode. The facta are to the contrary . This unhappy affair was the direct result of a mistake In judgment, " ` . - and a failure to follow verbal and written instructions. Our efforts in the development of a technical device of the type referred to, should not be permitted to take the burden of responsibility for .: sound judgment from the shoulders of safety personnel, but rather to 4. supplement such judgment by technical data when it Is possible to <3o so* Signed t iob'e'i't Echo, 4. i!-. Medical Director' 0 0 2 1 4 0n :->E /A'OiZ '%t; : 5. TAHK raPAlS-ISO A C C i m m - COUTXttBSTAL OIL COMPART ATTTSIA BBW MEXICO This tank was cleaned by aa contractor for . the Continental Oil Company on November 27$ 19^4 - Ilovenber 29, 194*, and observed by Mr. Eenington, Ethyl Corporation safety . representative * According to the management and Mr. Leoington all safety precautions were observed in the cleaning operations, in eluding complete changes of clothing, air-line masks, gloves and boots. Baths were taken by all workmen at noon and in th evening. Four men entered the tank in the cleaning operations end apparently the entile procedure was regular and according to safety regulations* As evidence of this is the fact that only on of the men who helped with the tank cleaning developed any signs of illness, and that :' these occurred in connection with the repair work in which he assisted. The sludge was put in a pit located about twelve feet from the manhole, but as the work progressed, it was found necessary to dig a long trench to hold th sludge as the fluid portion did not drain readily into th ground due to the type of soil. This sludge remained uncovered for two day and subsequently a question arose as to the possibility that vapors from this source had entered the tank, thereby providing the exposure experienced by the repair men. This, obviously, is a most unlikely explanation of the . :' latter exposure. The sludge was not covered immediately because of shortage of help. The tank was steamed on the nights of Bovember 29 and >>, and lecember 2 and during th day end night of Beceaber J5. Wet steam 3W < * A - s Cry oteam vos not available a fact accounted for presence of about :> - gallons of ftqpeous condensate In the tasdc In pools at various low spot* ovey the bottom when It was being made reacy ;or concrete, This water was drained through a . .tf..*- , hole made In the bottom of the tank a t the edge, ae there vaa no water draw-oil - 1 the tank remained..s^abowm until December 9 five days .... fib'-X-b after the last steaming Whan the concrete bottom vaa poured, 'here a; * ^ f *i . , ; y-., * vgs some question aa to vhetber nev ateel bottom was to be n #we tailed or a layer of ccnoret poured over the leaky bo item vith .ho idea of putting a metal bottom over the concrete i&*er. bh;i by the way would create a situation that would make it inpoasiblo to clean the bottom. Hr. Lenlngton inionaed the superintendent that if welding or Other hot work was to to done on the bottom, it would havo to be sand bleated and a side sheet removed, this vaa con sidered too expensive an undertaking, .he cuperiniendont slated that Itr. Lenlngtoa appi-oved the pouring of the concrete without special precautions after the thorough steaming and tooting for vapors and declared it safe from that standpoint. Hr. lenington left for another tank cleaning and later In the week went to Dallas to help Mr. Jeppe with the army school being conducted there at the time. He was finishing there and on his way back to Amarillo When the report on the trouble at Artesia was received. Ho other safety representative of the Corporation was present. Mr. Lenington by the way told me he had discussed this particular tank and the pouring of the concrete on Thursday, I believe, et D*H a s with Mr. Ball who, so Lenington reports, said . . ' . ho could see nothing vreng with the procedure. ?- concrete on the bottom and Ur. was given the contract Five day* had elapsed since the 8teeming, hut the refinery safety :. . man made three differat tests on the tank and reported it gas free for open vorhing and safe fro the viewpoint of explosive mixtures. The contractor had a total of (13) men working for him* This number includes six Mexicans At some time during the day all of these men with the exception of one were In the tank. Some, however, were inside only mcsentarilly, helping shift the trough or doing other work for a short time. The group of Mexicans spent their time in end out - at time shovelling gravel and operating the concrete mixer* Th actual working arrangement consisted of a small motor generator outside the tank for current for the light, and a email concrete mixer set up on blocks at the manhole, with a trough about six feet in length extending through th manhole into the tank. The concrete was dumped into the trough, and moved along into the tank from the outside and then distributed on the inside as the bottom was laid. who became violently ill'and succumbed, van the worker who followed the edge of the concrete, pushing, pulling and levelling it about the bottom and, as-1 understand, worked very hard. Others in the tank moved about to and from the manhole. By noon good progress had. bean made af ter approximately four* hours of work in the tank* Mr* ^ t t k felt weak and unsteady, but continued to work the remainder of the day. He complained to Mr. J. at noon, *he vaan*t feeling too good.* Mr* another workman, became somewhat ill at neon and during the after noon worked outside of the tank. The other men vorked as usual 0021405 he tank bottcw had bean instailed. Fro vhat I could learn no skin contact vsa made vith any portion at the inside of the tank. As the vork progressed ore and ore of it vas done on top of the concrete vlth the exception of Mr* vho vorked on the tank floor part of the tlxso. After finishing vork in the evening the non vent to their homes, same living tventy ilea away in the town of K&gger&an, Kev Mexico* The Mexicans lived nearby Ar teala and in the surrounding country* MtMaMkWk* d a t a Tank was blending tank #15 This tank is a small round top tank of Xo,tuo-hbl. capa city approximately sixty feet in diameter. There is a manhole opening near the bottom 25 inches in diameter and a vent on the 6roof h inches in diameter and a gauge hatch approximately inches in diameter. On the teak directly opposite fro the manhole there vere tvo openings about 6 inches fro the floor - on `Winch and the other a 6-inch opening. These ver the gasoline line openings and the line were disconnected and blanked off. There was no manhole opening in the roof. The above vere the only openings for ventilation into the tank and no side sheet vas removed during the pouring of the concrete vMcli vas approximately 8 0 $ completed, leaving about 4 cubic yards still to be poured to complete the job. Through one Of tha -11 e w o l t e U n * opaning. *t the iot tom of th. tank a compressed air ho vao introduced and it supplied air from th compressor in another part of the refinery and vas in operation while the men vorked. ,, , .,, ,, 9. Relative to the bottom the superintendent of the refinery, '; . the contractor end Mr* Lcnington all atate that it had no large holes or openings in it. The contractor saw a fee (three or four) holes the else of a pencil, but it would be rather difficult to see state openings ae the underlying soil would he the same color, and there might have boon many fine holes. The bottom v&s springy when walked on which would allov settling vhen heavy conerote was : applied It is possible, of course * that there were larger holes than those described, and it is possible that sludge vac present in considerable quantity under the tank on the ground. The charac ter of the soil, as mentioned elsewhere, was such that it v&s not readily penetrated by the sludge and therefore the absence of wetness around the edges of the tank, on the outside, does not : _. prove that there was not a considerable quantity of material under the tank. There was, in fact, a spot of wetness, about six by twelve inches on one side of the tank* As to spiking of this tank in the past there is no his- . . . . tory. It is an old tank, in service a number- of years and addi tional lead may have been introduced directly Into the tank at sometime or other. The superintendont said it had never been done to his knowledge. However, in recent years, there have been three superintendents in charge of this refinery. Qgsible Source of gad . . _ There was ease question at the outset as to load being the causative factor in these cases because of the rapidity of the onset of symptoms. However, as th illness progressed, it was KF 0021407 10. find th source of lead. The bottea of the tank was fowfiffcb covered and could not be seen but Mr* Gillespie the refinery superintendent Hr. m H H * the contractor and Hr. Leningtcn said there vere no large holes in the botton. Mr. fH f liasid be s&v three or four small holes about the also of a lead pencili Hr* Gillespie said it vould hold a viiter bottom of four to sis inches for a couple of months but since the soil allows poor absorption and drainage as observed in the sludge pit it would be possible for fluid to pocket beneath the bottom. Around the edge of the tank in only an# place was there any significant wetting of the soil from the leaky hot testa. However the interval of five dasa between the hot steaming and the concreting could allow vaporisation of the contents below the bottom. Cn the other hand one might expect some gasoline vapor to be in the tank also but it tested gas fra or within safe limits before work was begun. This could be explained by the water bottom which the superintendent said was always kept in the tank because of the-leaky bottom so gasoline may have been kept out of the area under the tank sufficiently to give one this picture. ; . K ' . She bottom in this tank was springy when walked on and the heavy concrete on th bottom may have b o m a factor in pushing up any trapped below through the holes remaining in th floor ahead of the concrete. ' -j . - In light of th fact that seme of th men in the tank complained of irritated eyes and ^running no" I tried to find i ' -_ ', a source of dry triethyl salts* This would mainly have to corn . from the idee since th bottom was wet or damp. From previous findings cn sides of tanks I questioned this but thought the air A'F 0021408 u' . 7' * motion loosening up some dust fro the sides to account for the .. above symptoms, ;' In checking into the sir line bloving into the tank it vas turned on vith the valve half opened as no one seemed to know vhere it vas set during the vork in the tank* In a short tiara air vas moving out of the manhole* and Trees the outside* vapor could he seen casing out of the vents on top-- -possibly from the moisture from the concrete. A piece of cloth vas obtained at the store and fastened over the manhole and allowed to remain there three and a half hours vith the air valve half open. This vas removed and folded to keep the exposed part together and placed Immediately in a paper bag for analysis A control piece of the same cloth vaa kept. This would only disclose case lead vapor in the tank* but when done most of the floor vas covered. A sample of the sludge from the tank vaa obtained from the sludge pit* and a cample of scale from th side vail of the tank ' I*. J. Schradin January 25* 1$$5 - 0021409 Semples of urine and blood received from men. involved in cementing bottom the Continental Oil Company, .(Dr* fchradin) Artesla, fiev Mexico, Urine Blood Ktt ; . "Analysis Sumter m~69H9 flB B V \ Volume m. 9j Mg. Pto/U. O.8 0 Analysis j speezropy^voic Huaber "Weight Mg* ft/100 g. Crams \ ViA*S95`d *f*>O> 0 .12 5 , WtKKR, ^AA-6947 10 0 0 .8 0 UA-69^8 ** *4A-69*5* 100 0.13 4kfio'ijk0 12.9 0 ,0 6 5 '. wel Cra 13 * 15 . 14. * Specific gravity not taken, but urine vas colorless indicating dilution* .. . ............................. : .............................. . . ->; --- " Ssatplee Collected*- Samples deceiveds. 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