Document zQKMKprw9xB3rjDY7bLOwzQRn
SM-32 (REV. 5-78)
Shell Oil Company
Interoffice Memorandum SEPTEMBER 22, 1986
FORM:
SR. INDUSTRIAL HYGIENIST, HEALTH & SAFETY, MFG. & TECH.
TO: SEE ATTACHED DISTRIBUTION LIST
SUBJECT: ASBESTOS SAMPLING PROCEDURES
As you are aware, OSHA in Appendix A of the new Asbestos Standard, pub lished a revised sampling and analytical method. Significant elements of this method include:
1. Use of a 25mm MCE sampling cassette with 50mm extension cowl (Todd Morman reports that these are now available).
2. A recommended airflow rate of 0.5 - 2.5 LPM for personnel monitoring. Higher flow rates are permitted for area samples.
3. A prohibition against using packing material that has a high electro static charge on its surface (such as polypropylene pellets). Cas settes should be tightly packed for shipment to minimize movement.
4. A minimum of two (field) blanks should accompany each set of samples. The number of blanks to be submitted is determined by a 10% rule.
Presently, the Westhollow IHL is setting up to do asbestos counting by the OSHA mandatory method. In the interim, the newer 25mm cassettes are being sent to Hager Laboratories.
While the (NIOSH) method previously used by the Shell I.H. lab gave a count of all fibers present, Hager Laboratories is using polarized light to identify fibers which do not resemble asbestos (otherwise referred to as non-birefringent fiberij. Such fibers, when rotated in the presence of polarized light, become transparent. Birefringent fibers on the other hand reveal a change in color. Fiberglass and ceramic fibers generally appear as are non-birefringent. Hager Laboratories report that often 20% or more of the fibers are so classified; however, this would obviously be dependent on the material involved. Westhollow's IHL is planning to be able to make this qualitative determination in the future.
It is recommended that when sampling for asbestos, one of the following statement be entered on the I.H. sampling form under "Possible Interfer ences/Instruction" :
Non-asbestos insulation may be present, or
No known interferences
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Based on this information, Westhollow will when indicated perform the additional determination using polarized light. In addition, this determination will also be made regardless of the potential interference notation where the fiber count exceeds 0.5 f/cc. If you have any questions concerning this, please let me know. Thank you.
P. J. Snyder PJStbjd cc: A. D. Ditmar
G. L. Greene D. H. Morman J. L. Rivard
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INDUSTRIAL HYGIENE REPRESENTATIVES
ANACORTES REFINERY D. D. SMART
DEER PARK MANUFACTURING COMPLEX A. F. SCHMIT
GEISMAR PLANT M. T. BARCLAY
MARIETTA PLANT M. W. HERSHMAN
MARTINEZ MANUFACTURING COMPLEX M. B. KOVACEVICH
NORCO MANUFACTURING COMPLEX A. K. MENARD
ODESSA REFINERY E. N. GEE
TAFT PLANT J. J. DELAUNE
WILMINGTON MANUFACTURING COMPLEX S. V. SEVER
WOODBURY PLANT R. NOCCO
WOOD RIVER MANUFACTURING COMPLEX W. M. CUNNINGHAM
HEAD OFFICE T. A. COLANGELO R. J. DUHE R. E. GREEN C. L. HARING L. D. HEUGATTER R. K. JONES J. D. RANSDELL D. L. TACKETT
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