Text For Citation: 01 Item/Group: 001 Hazard: CHEMICAL

Section 5(a)(1) of the Occupational Safety and Health Act of 1970: The employer did not furnish employment and a place of employment which were free from recognized hazards that were causing or likely to cause death or serious physical harm to employees in that employees were exposed to the hazard of sudden reaction runaway and uncontrolled pressure rise: On 8/16/91, one (1) chemical operator in Building-16 was adding nitrosylsulfuric acid (40%) to the Pflaudler five hundred (500) gallon glas s lined kettle (Kettle #2) during a diazotization reaction, in the manufactur e of Intrasperse Blue GFD Base,a diazo-dye intermediate. The critical temperature was not maintained,therebyleading to a self-accelerating decomposition and a violent pressure increase. The manhole to the kettle was blown thru the room of Building-16 and the corrosive contents of the kettle were spewed throughout the entire building and outside onto the adjacent yard area. Adequate engineering controls and work practice safeguards were not in place to minimize the possibility of a runaway/uncontrolled decomposition. Among other methods one feasible and acceptable abatement method to correct this hazard is to establish administrative and engineering controls over the work being performed that will include, but not necessarily be limited to, the following provisions: (A) Chemical Process Hazard Review Conduct a chemical process system safety review. Predict upsets and estimate their frequency and probable consequences. Operating parameters, procedures and/or process control instrumentation determined by this review to be critical for the safe manufacture of Intrasperse Blue GFD base shall be designed and constructed for redundancy and back-up to assure maximum feasible safety to employees. This review shall be of a type generally recognized in chemical processing industries (such as What if, Cause/Consequence, FMEA, HAZOP, Fault Tree, etc.) and shall include, but not necessarily be limited to, the following: (i) Review process flow sheets to determine possible emergencies during start-up, normal operating, and shut down condition, and to evaluate the consequences of excessive temperatures and pressures or variations in material control at all phases of the reaction. (ii) Review of a piping and instrumentation diagram (P & ID) to assure that controls and instrumentation will detect unusual conditions and that the system will AUTOMATICALLY shut down or can safely shut down in the event of operator or equipment error or in the event of excessive temperature, loss of agitation, loss of cooling water or any other condition which could lead to dangerous decomposition. (iii) Review of the chemical reaction process considering potential problems arising from abnormal temperature rises, pressure rises and rates o reaction; improper addition of reactants and material flow stoppages. (iv) Review of operating equipment used in the manufacture of Intrasperse Blue GFD base considering the adequacy of design and fabrication; effects of corrosion, erosion and metal fatigue, potential for exceeding design limitations, equipment leaks and spills; equipment malfunctions and failures; plus adequacy of maintenance, repair and replacement programs. (v) Review of operating design and the potential for operational errors considering detailed operating descriptions and standard operating procedures to minimize the potential for operator injury. vi) Review and assure control instrumentation reliability, clarity, accuracy and where critical parameters are monitored, engineer in redundancy with audible annunciators to warn of pending upset condition e.g. excessive temperature and/or loss of agitation. (vi) Assure raw material purity on a more frequent basis. (B) Review and Revision of Standard Operating Procedures. (i) Update written detailed descriptions and Standard Operating Procedures for the manufacture of Intrasperse Blue GFD Base, to assure safe start up and processing within critical limits and to provide safe shut-down of equipment in the event of abnormal conditions. These procedures shall address, but not necessarily be limited to, the following: (1) Start-up procedures for Intrasperse Blue GFD base that will include checks to insure process equipment and controls are functioning properly and that emergency devices are in proper working order. (2) Emergency shut down procedures for the Intrasperse Blue GFD base that will define abnormal operating conditions and specify Sequential steps for safe shut down of equipment or timely evacuation of operating personnel plus proper removal techniques of any residual flammable, unstable, corrosive, or toxic, materials. (3) Update provision for purging of the system by installing emergency solenoid activated "dump" valves and adequate inert pressure to "blow over" contents which can be activated by the operator quickly and safely. (C) Operations and Safety Controls (1) Design reagent charging mechanisms that will fail safe or otherwise stop any reagent charge which is contributing to an upset condition such as: (i) loss of adequate cooling water pressure (ii) loss of inert atmosphere in the reactor (iii) too low operating temperature (iv) too high operating temperature (v) loss of loss of agitation/loss of power to the agitator (2) Provide audible alarms that will indicate the above upset conditions to the operator. (3) Maintain an inert atmosphere and install an explosion prevention system(s) in accordance with NFPA-69 (1986 edition). (D) Adequate Emergency Relief Devices Insure that emergency pressure-relieving devices on process kettles are sufficiently rated to carry off the maximum generated or supplied quantity of liquid and/or vapor based on the physical phenomenon of two phase flow while permitting no more than a ten percent rise above the maximum allowable working pressure within the vessel when these devices are blowing. (1) Assure that these devices function as designed via periodic preventitive maintenance