Document 063aQ4QEbZ9yQ6Ybb8Jzm8Zeb

Monsanto *9 .ate subject R. L. Bourget - Springfield, Mass. April 17, 1974 Work Practices --- Issue #2 REFCftENCE to ALL PVC PERSONNEL cc.- A temporary standard for exposure to VCM has been issued by the Occupational Safety and Health Administration COSHA) following an intensive, but as yet incomplete Government investigation into the VCM health concern. The standard requires a maximum exposure limit to personnel of 50 parts VCM per million parts of air (PPM) and requires the use of fresh air breathing equipment in areas where there is a potential for exceeding this limit. The temporary standard is in effect now and will remain in effect until a permanent standard is formulated and issued. The permanent standard will be based on a full and comprehensive Government investi gation into all aspects of the issue. Several short-term engineering modifications and procedural revisions have been made throughout the area to keep normal VCM concentrations below the 50 PPM ceiling. Much of the equipment in use for this purpose is temporary and will be replaced with permanent installations as soon as possible over the next several months. There are, however, a few situations which exist that require the use of fresh-air breathing equipment. The work practices presently being released (Issue #2) are based on the original issue (3-5-74) and the new OSHA standard (4-5-74). As you will notice, several of the original work practices have been retained, some deleted, and others made optional. This is consistent with my earlier statement that changes will occur as new information is developed. Several new mandatory practices have been added which relate principally to the new Federal Law (OSHA). Again, however, I must point out that these practices are subject to additional changes, particularly as OSHA works toward the permanent standard. Each of these practices will be explained to you by a member of supervision. They are effective immediately, but for them to remain effective in achieving what they are designed to do protect worker health - we will need your cooperation. I am confident that I can count on your support. - RL3/SBN R. L. Bourget RSV 0006184 _ - jui effective Immediately April 16, 19 7 4 MANDATORY WORK PRACTICES A. Ventilation General -- Ventilation changes have been made in both 88 and 84 Bldgs, to effectively reduce concentrations of VCM in the kettle floor atmospheres below 50ppm during routine operations. The fol lowing work practices describe how these new systems are to be used. 1. Whenever a kettle is open the following ventilation require ments apply. a. All normal exhaust fans on. b. Coppus blower exhaust system in operation on the open kettle. c. In 84 Bldg, only, the Coppus fans mounted around the ketti floor will be on. 2. Continuous negative pressure ventilation is required whenever anyone is inside a kettle, slurry tank or latex tank. The backup Coppus blower will be used for this operation, with the inlet hose placed at the bottom of the vessel and the discharge hose exhausting outside the building. 3. In any operation which involves emission of VCM liquid or vapor into the kettle room, the following ventilation re quirement applies. a. All normal and emergency exhaust fans on. 4. Because openings in the building destroy the ventilation air flow patterns, the following will be closed at all times. a. All kettle floor and lower kettle floor doors and windows in 84 Bldg. b. All door and windows leading into the lower kettle floor or packout areas of 88 Bldg. 5. When preparing a kettle for entry, a Coppus blower will be used to exhaust the kettle interior through the manhole under negative pressure for at least 15 minutes nrior to entry. The discharge hose will be exhausted outside the building. Once this operation has begun the fixed kettle exhaust blower may be shut off. RSV 0006185 mandatory work practices Page 2 B. VCM Source Isolation or Disoersion General -- Several significant sources of VCM exposure have been reduced" through equipment modifications. The following work practices apply to these items of equipment. 1. All slurry tank and latex tank covers will be closed and dogged down unless absolutely necessary to have access to the tank interior. Routine level checks and inspections will be made through the sight glasses. 2. The 84 Bldg, seed strainer will be kept closed' and dogged down when not in use. Mote: The walls of the RVCM compressor rooms have been removed to allow natural dispersion of VCM vapors. C. Respiratory Protection General -- Most of the routine situations involving potential exposures to VCM in excess of 50ppm have been dealt with in section A. and B. above. However, any time there is a deviation from the practices outlined in sections A. and 3. fresh air breathing equipment (Scott Air-Pak or bulk system) must be worn. 1. During operations which involve breaking into VCM liquid or vapor equipment, a yellow tape carrier will be erected around the job at a distance of 10 feet. Such operations include: breaking into VCM liquid or vapor lines or valves, changing fil ters or strainers, draining the 88 Bldg, vent knock-out tank, draining the 84 Bldg, inerts bleed knock-out tank, opening the slurry tanks, latex tank or 84 Bldg, seed strainer, removing pop valves or inserting or removing blanks in VCM lines. (Work on dump T's, slurry baskets or slurry lines are not included if they can first be flushed with water for a period of S minutes. 2. All personnel within the safety tape barrier described in 1., above, will wear fresh air breathing equipment until the VCM source has been aired out and flushed with water. 3. All personnel engaged in draining water from a VCM or RVCM tank, bleeding an RVCM tank or breaking a vapor lock in 84 Bldg. VCM or RVCM pump will wear fresh air breathing equipment continuously. 4. Dust mask protection is required for BOrs and ZPA's while operating packout equipment, and for all personnel perform ing dusty housekeeping operations. This includes dust ccllec-o entry (Pangborn and Pulsaire). RSV 0006186 `'.-.':da?ory work practices Page 3 5. Anyone discovering a minor VCM leak will immediately attempt segregate leak by shutting off valves or shutting off pumps, and block off the area ten feet around the leak with yellow safety tape. Continuously hose down the leak with water from outside the barrier until the leak is topped. Fresh air breathing equipment is not required for personnel outside the barrier. D. Housekeeping General -- Although the VCM emission potential from dried resin is slight, accumulations of resin which are allowed to stand for long periods may eventually give off significant concentra tions of VCM. The following work practices are designed to prevent these emissions. 1. Minor resin spills will be cleaned up immediately. In addition, the 84 Bldg, bagger room and warehouse and the 83 31dg. packout area will be swept once per shift. 2. All other building areas will be washed once per week. 3. All PVC will be stored in closed containers when inside building. 4. A special overhead structure cleaning effort will be made once per month. 5. The 84 Bldg, conveyor dust catcher in the warehouse will be emptied daily. E. Personal Hygiene General -- Food items left in contact with VCM vapor or PVC dusr may absorb a significant amount of VCM. The following work practices are designed to avoid this, and to avoid exposing personnel who are. not properly prepared to follow all our other work practices. 1. Mo food, drink or eating utensils will be used or stored in the PVC operating areas. These items are permitted in the 88 Bldg, smoking room and all offices except the 84 Bldg, office. 2. Transients (personnel not in area fulfilling assigned functic will not be permitted to enter any PVC operating area unless authorized by a member of PVC supervision. RSV 000618? \H RECOMMENDED WORK PRACTICES General -- The following work practices, while not manda tory at this time, are strongly recommended for all per sonnel. These practices provide further protection agains exposure to VCM. 1. Wear full coveralls while in the work area and change them twice per week. 2. Wear rubbers or other shoe covers and gloves while in the work area. 3 SDO's, BO's, EPA's, PO's and anyone cleaning a kett should wear head covers while in the work area. A1 other personnel are encouraged to wear head covers. RSV 0006188