Document 6bw96VKjB43wq3rK4K0985X3o
. MANUFACTURING CHEMISTS
ASSOCIATION
1825 CONNECTICUT AVENUE, N. W. WASHINGTON, D. C. 20009 (202) 483-6128
READER'S COMMENT
"Please refer to Case History No.1920 as published in your Accident Case Histories of May 1973, in which an employee was burned by steam from a hose on a tank car using quick-opening couplings.
"The solution to the problem as pub lished should not be by the use of bleed valves only, but should also discontinue the use of quick-couplings on steam hose as they are apt to blow off and then the hazard is much greater. We would suggest a- Boss type connection on any steam hose. Piping - where practical - should be used because pipe is much safer than hose."
CASE HISTORY NO. 1931
Oxygen System - Flash Fire
Description: Employee received flash burns to his hand and chest when he opened a nee dle valve to an oxygen manifold system. The valve had been newly installed, and employee did not know it contained hydro carbon oil lubricant in the stem and pack ing area. Apparently the oxygen at 2,000 pounds pressure ignited the lubricant and the valve failed in a cutting torch effect. The 80% polyester - 20% cotton shirt he was wearing ignited and could have been a contributing factor in the severity of the burns. Cause:
1. Lack of awareness of the extreme precautions that must be taken around oxygen system to assure safe operation.
2. Failure to investigate standards, procedures, and other sources to assure safe fabrication, instal lation, and operation.
preventive Measures: 1. Education and emphasis to assure
July 1973 Issue
that all employees know of the hazards involved in oxygen in stallations . 2. Some other means of heating the switches will be devised.
3. Special newsletter and flyer pub lished to communicate details of incident.
4. Guidelines for the location safe ty manual will be developed to specify appropriate selection, use, cleaning, and maintenance of all equipment to be used in oxygen service.
CASE HISTORY NO. 1932
Release of Flammable Gas
Description: A reactor was charged with 250 gallons of vinyl chloride with the bottom valve and sewer valve open. Al though a serious hazard was created by this release, no one was injured and no equipment was damaged.
A helper was' working with the mechan ical cleaner operator to prepare #2 and #3 reactors for charging. It is part of his job to close the bottom and sewer valves. The helper related that he normally waits until a pair of reactors are cleaned be fore closing the bottom valves, but in this instance, he closed the valves on #2 reactor while the mechanical cleaner was still running in #3 reactor. At this time he put the initial charge water in #2 reactor and then proceeded to other work while waiting for #3 reactor. Upon returning later, he thought he had closed the bottom valves on #3 reactor the same time he closed the valves on #2 reactor, so he proceeded to add the initial charge
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water.
The charging operator stated that prior to charging reactors #2 and #3 he checked and tagged the bottom valves on ir2 reactor and saw the valves open on #3 reactor. Later he proceeded with the charging of #2 reactor and noted the help er putting water into #3 reactor. He then proceeded with the charging of #3 reactor, at which time the gas release occurred. Cause: The specific cause of this acci dent lies in the failure of the helper to close the bottom valves on #3 reactor and the failure of the charging operator to check and tag the bottom valves prior to charging. Preventive Measures:
1. Appropriate disciplinary action was given both the helper and the charge operator for not fol lowing operating procedures.
2. This accident was reviewed in all departmental safety meetings.
CASE HISTORY NO. 1933
Static Spark Ignites Methanol-Acetone Mixture
Description: A chemical operator suffered first and second degree burns of the face, arms and chest when a methanol-acetone mix ture was ignited by a static spark. At the time the operator was trying to push some crystals into a centrifuge drop line at the bottom of a crystallizer using a nonconductive Teflon rod, when the vapors ignited and caught him as he stood over the manhole. The injured was admitted to the hospital and his lost time is es timated at 47 days. Preventive Measures: There are obvious lessons to be learned from this incident.
1. The man was wearing a sweater of synthetic material which ig nited, melted, and contributed to his burns, and may even have contributed to the static build up on the rod. Personnel must be warned against these materi als in chemical operations.
2. Vessel manholes should not be permitted to be opened indis criminately, especially when there are flammable or toxic
solvents in the vessel. 3. Where flammable vapors in the
vapor space are in the explo sive range we should not intro duce objects into the vessel which can be a source of ignition--especially non-conductive rods or scoops. 4. Nitrogen was piped into the drop line to be used for facilitating the flow of slurry to the centri fuge. This was not used. In addition nitrogen was piped to the bottom valve through a 3 cfm capacity rotameter to avoid ab sorption of air and control prod uct color. Investigation showed that there was a slight flow through the plugged nitrogen rota meter. This flow was not suffi cient to inert the vessel. It is important to reaffirm peri odically with each supervisor that he has instructed his work ers about the differences between nitrogen for inerting and for other purposes.
CASE HISTORY NO. 1934
Operators Exposed to Toxic Gases
Description: Four men became ill while working in the Liquids Department with one man requiring hospital treatment. At the time,the men were handling a num ber of chemicals including amines, hydro chloric acid, and formaldehyde when one or more of them, or even a combination, created sufficient vapors or gases which resulted in these illnesses. Preventive Measures: Both immediate and long range steps have been taken to pre vent a recurrence including rearrangement of production schedules, better housekeep ing and major equipment changes on pumping, piping and vent systems. The man treated at the hospital lost 1 day of work.
CASE HISTORY NO. 1935
Valve Opened Unintentionally
Description: A contractor welder received
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