Document 2NKjadQjRZMYxJ5BJa0oLdppp
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i
Interoffice Communication
To S. E. McGuire
From Date
H. J. Hall January'3, 1984
Subject
VCM WARNING LABELS
The enclosed correspondence from B. F. Goodrich establishes their
position on VCM warning labels.
I believe we need to review their
action in this area. We have consulted outside counsel on this subject
in regard to combustion warnings on PVC. Perhaps, we should also here.
We should also review our own technical data in this area to determine what further work is necessary, if we wish to pursue a similar course.
TjJi
H. J. Hall Associate Director
oi'io j ruin*, a u
ELK, Houston
000
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Th BFGoodnch Company Chemical Group 6100 Oak Tree Boulevard Cleveland. Ohio 44131 216-44 7-6000
Please review this letter carefully and then pass it on to the person in your company responsible for environmental affairs.
On October 7, we advised you by letter of our intention to remove the warning labels on most of our GEON polyvinyl chloride (PVC) resins and compounds. This decision was based on extensive modeling studies and actual measurements which showed that resins and compounds, containing 8.5 ppn or less of residual vinyl chloride monomer (FVCM) would not trigger
the 0.5 ppm "action level" as defined by the Occupational Safety and Health Administration (OSHA).
For purpose of clarification, following is the list of products from which labels will be removed:
1. All prime suspension resins. 2. All prime dispersion resins. 3. All prime ness resins, including 220X2 and 221 resins. 4. All prime compounds.
The following classes of material will be labeled if the KVCM levels are greater than 8.5 ppm:
1. Blending 212 and 213 resins. 2. Off-grade and scrap suspension resins. 3--.....-Off-grade-- dispersion resins. 4. Off-grade and scrap mass resins. 5. Off-grade and scrap compounds.
- - -----------
This new labeling policy will become effective December 5, 1983, however, since we will be shipping from existing Inventories, you may continue to receive labeled material for seme weeks.
If your canpany wishes to continue receiving labeled material, regardless of the KVCM levels, please notify us and your records will be marked accordingly.
Enclosed is a new technical service bulletin dealing with our studies and conclusions on this subject. Please review and, if you have further questions or concerns, call Jim Tan2illi on the BFG PVC Interchange, 1-800-321-2916.
Sincerely
BFGCODRICH CHEMICAL GROUP
JFG/mla Fnc\osure
yames F. George Vice President,^.Sales
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Within the past several years,
significant advancements have been made in the PVC industry to
minimize employee exposure to vinyl chloride monomer (VCM). Improvements in PVC manufacturing processes to reduce residual vinyl chloride monomer (RVCM) content of finished resins have been a key factor in maintaining acceptable atmospheric vinyl chloride monomer levels (AVCM) in work areas during storage, shipment and thermal processing.
Our knowledge and understanding of the diffusion1-2 of VCM out of finished PVC resins under storage
)conditions and during thermal processing are also much improved based on extensive experimental data, modeling studies and work place monitoring. Based on these facts, it is concluded for PVC resins and compounds with 8.5 ppm RVCM or less, the AVCM will be less than 0.5 ppm over an 8-hour day. The
storage, transportation andthermar ' processing of these products will result in worker exposure less than 0.5 ppm AVCM over an 8-hour day.
Diffusion of VCM
The diffusion of VCM out of PVC resin is dependent on several critical factors:
Particle size
Particle porosity Temperature The concentration of AVCM that
can accumulate in enclosed work areas is additionally affected by:
Resin quantity/storage volume ratio
Ventilation rate of work area Residence time RVCM content of the resin Using the above variables and
jdata obtained from diffusion /experiments, models have been
developed that allow determination of the maximum concentration of AVCM that can occur under a wide variety of
conditions. Additionally, monitoring of work place atmospheres has been
carried out for a number of years. The results of this "real world" monitoring have confirmed the validity of the developed models.
Storage and Warehousing of Resin
The development of a model that allows determination of AVCM in large storage areas presents a number of special problems. Many types of resins containing different quantities of RVCM are frequently moved in and out of the storage enclosures. Additionally, the diffusion rate of VCM out of resin at room temperature is very slow and does not follow the ideal behavior exhibited at higher temperatures (above the glass transition temperature). Consequently, it was necessary to study the behavior of stored resin in large-scale experiments designed to simulate warehouse storage conditions. The variables and ranges studied included: " Temperature -- 74 to 115F
Ventilation rate -- 0.5-3.0 turnovers/hour
Loading (PVC volume/storage volume) 11-34%
Resin RVCM -- 0.01-123 ppm Storage time -- 1-170 hours
Using a Computer Optimized
Experimental Design (COED), 24 large-scale experiments were selected to study the above listed
variables to define their effects on atmospheric VCM in a storage compartment or warehouse. A multiple correlation analysis of these experimental results permitted the derivation of a model3 which can be used to predict any combination of the variables studied. Thus, it is possible to predict the atmopsheric concentration of VCM in a storage area under the worst conditions of temperature, ventilation rate, loading and storage time. Based on these considerations, the AVCM is less than 0.5 ppm over an 8-hour day
when the RVCM content of PVC resin is 8.5 ppm or less.
The validity of this model was confirmed by ambient air monitoring
in BFGoodrich warehouse facilities in three locations over a one-month period. The measured atmospheric VCM level in these warehouse
facilities was in excellent agreement with predicted results based on the developed model. Thus, "real world" monitoring was used to confirm the model based on experimental data. A more detailed description of this work is reported in the Journal of Vinyl
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Technology (Voi. 1, No. 3, September, 1979).
Transportation of Resin
Since compartments used tor transporting PVC resin (such as trucks and railway cars) are in effect
a mobile warehouse, the previously described model for a warehouse can also be applied to shipping compartments, The variables
included in the transportation model included:
Temperature Ventilation rate Loading Resin RVCM content Residence time Obviously, the range of some of the variables is somewhat different than in a warehouse (e.g., loading, ventilation and residence time). As in the warehouse study, the derived model was used to determine AVCM for worse-case situations, i.e., high
loadings, high ambient temperatures, low ventilation rates and longest expected residence time.
Based on the above modef, AVCM in a shipping compartment is less than 0.5 ppm over an 8-hour day provided the resin RVCM content is below 10 ppm. Again, as in the warehouse study, a significant amount of "real world" monitoring of atmospheric VCM in shipping compartments has been done to confirm the validity of the transportation modeling study,
Thermal Processing of PVC
In the thermal processing of PVC, the variables affecting the relationship between RVCM and atmospheric VCM are, of course, somewhat different than those expressed for warehousing and transportation. A similar approach to modeling can be used, however,
OSH/. Action Level
Percent of VCM lost in thermal processing
This latter variable, percent of VCM lost in thermal processing, has been determined experimentally for a wide variety of resins and compounds.
Again, using a set of worse-case
conditions, the developed model was
RVCM ppm
when these variables are considered: RVCM content of resin
or compound Volume of processing building Processing rate, pounds/hour
Ventilation rate, air turnovers/hour
Building temperature
used to determine the relationship between RVCM in resin or compound
and atmospheric VCM in .the work place. This model shows that the AVCM is less than 0.5 ppm over an
8-hour day when the RVCM level is
below 32 ppm. A significant amount of personnel monitoring has also been done in PVC thermal
processing areas to confirm the validity of the developed model.
Summary
The relationship between RVCM in PVCresirr or compound and'AVCM
in work place areas, used for storage, transportation and thermal processing of PVC, has been subjected to intensive study. Models
have been developed to determine AVCM level under the most adverse conditions. The validity of the models has been confirmed by "real world" monitoring. When the RVCM content is 8.5 ppm or less, the storage, transportation or thermal processing
will result in worker exposure less than the action level of 0.5 ppm AVCM during an 8-hour day.
5 A.R. Berens, Polymer Preprints. 15, 203 (1974) ! A.R. Berens, L B. Crider. C.J. Tomanek & J.M. Whitney, Journal ot Applied Polymer Science, 19. 3169 (1975)
3 L.B. Crider, M.M. O'Mara, R.L, Bowtes, Journal of Vinyl Technology, 1,168 (1979)
^Goodrich
The BFGoodrtch Company, Chemical Group/6100 Oak Tree Boulevard, Cleveland. Ohio 44131
Chemical Group
The information contained herein is believed to be reliable, but no representations, guarantees or warranties of any kind are made as to its accuracy, suitability for particular applications or the results to be obtained therefrom. The information is based on laboratory wort with small-scale equipment and does not necessarily indicate end product performance. Because of ihevariations in metnods, conditions and
equipment used commercially in processing these materials, no warranties or guarantees are made as to the suitability of the products for the applications
disclosed. Full-scale testing and end product performance are the responsibility of the user. BFGoodrich shall not be liable for and the customer assumes all risk and liability of any use or handling of any matenal beyond BFGoodrich's direct control.
THE SELLER MAKES NO WARRANTIES. EX PRESS OR IMPLIED. INCLUDING, BUT NOT LIMITED TO. THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PAR
TICULAR PURPOSE. Nothing contained herein is to be considered as permission, recommendation, nor as an inducement to practice any patented invention without permission of the patent owner.
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