Document v9Y8Rgam28bVmVQ8oDj13D4q

MONSANTO CHEMICAL l 4PANY Location Texas City, Texas Date October 4, i960 Subject Bypass Valves To i \Plant Manager's Safety Boardj sc 16518 A fire occurred recently in one of the operating depart ments which was caused by the failure of the operator to shut off a bypass valve around the fuel gas control valve. This particular incident provides the opportunity for me to discuss with you indications of potential problems in your particular area. In the investigation of this particular incident, it was found that for sometime it had been necessary to operate with the bypass around the control valve opened slightly in order to attain the required operating condition. Routine flow through the bypass valve of a control valve setup was one of the hazards listed in the Process Hazard ^Q.c.1^0^ Committee Report of 1957. The hazard lies in the fact Ic.^- that control Is no longer maintained if the bypass valve op. - ^ . is opened. When it becomes necessary to open the bypass "`V* valve to routinely attain a set of operating conditions, it Is fairly obvious that the control valve is undersize 1 f j ,^and should be corrected. ^c^Also, In this incident a delay in proper blocking In the 'h equipment caused the emergency to last longer than it should have. The inference here, and is in fact true, is that the operator did not know how to block in the /equipment properly. This is an indication that additional ) refresher training is necessary in order to maintain the ) efficiency of the operating group and the safety of the f fr* * Larea. .yhit*r Vv' .l ? These two hazardous situations are brought to your attention ? for the purpose of action by you if similar situations exist ^^ In your area. This incident would indicate that in some \ items emphasized by the Process Hazard Committee, we are / b tending to slip and the Board should take action to re- ^-- verse this trend. CjO-- tsb^rc^yo <~yU-vi--r-%> -1" b /sv-iCjuulAsdtt <?aci-C <cv // cA/?* sb- SUlt , com o<-^JLs cO-zJ-S ^Ilc *_<,<$ cl /V> tzb-A tOffi-l 4. 2 -.A t Ii c.t. f it j C. L. Gilmore LAM024426 r> ctc'C? -C o.aj<U, S-t'p, <U^J P-y b. .-J- V ru.< ( *y Ct-c> ' j <a^u/