ASTM E1437-98

Standard Practice for Handling Silicon Carbide Whiskers (Withdrawn 2007)

SCOPE
1.1 This practice describes recommended procedures for the safe handling of respirable silicon carbide whiskers and fibers. Respirable silicon carbide whiskers and fibers are considered to be those with diameters less than 3.0 [mu]m, or silicon carbide whiskers and fibers that contain a population with diameters less than 3.0 [mu]m.
1.2 Fragments of silicon carbide fibers that meet the size definition of silicon carbide whiskers are covered by this practice.
1.3 The information contained in this practice is intended for use in a material safety data sheet (MSDS) for silicon carbide whiskers.
1.4 Other materials may be present in the final product (for example, crystalline silica); information specific to these additional materials should be included in each manufacturer's MSDS.
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard and precaution statements, see Sections 4, 6, 8, and 9.
WITHDRAWN RATIONALE
This practice covered recommended procedures to reduce health and safety problems, which may arise during handling of respirable silicon carbide whiskers. Respirable silicon carbide whiskers are a crystalline silicon carbide (SiC) fiber, approximately cylindrical in shape with a diameter less than 3.0 m and an aspect ratio equal to or greater than 5:1.
Formerly under the jurisdiction of Committee E34 on Occupational Health and Safety, this practice was withdrawn in 2007 in accordance with section 10.5.3.1 of the Regulations Governing ASTM Technical Committees, which requires that standards shall be updated by the end of the eighth year since the last approval date.

General Information

• Status: Withdrawn
• Publication Date: 09-Apr-1998
• Withdrawal Date: 15-Feb-2007
• ICS: 71.060.50 - Salts
• Technical Committee: E34 - Occupational Health and Safety

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:E1437–98
Standard Practice for
Handling Silicon Carbide Whiskers
This standard is issued under the fixed designation E 1437; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 6057 Test Method for Determining the Concentration of
Airborne Single-Crystal Ceramic Whiskers in the Work-
1.1 This practice covers recommended procedures to reduce
place Environment by Phase Contrast Microscopy
health and safety problems which may arise during handling of
D 6058 Test Method for Determining the Concentration of
respirable silicon carbide whiskers. Respirable silicon carbide
Airborne Single-Crystal Ceramic Whiskers in the Work-
whiskers are a crystalline silicon carbide (SiC) fiber, approxi-
place Environment
mately cylindrical in shape with a diameter less than 3.0 µm
D 6059 Test Method for Determining the Concentration of
and an aspect ratio equal to or greater than 5:1.
Airborne Single-Crystal Ceramic Whiskers in the Work-
1.2 Fragments of longer silicon carbide fibers that meet the
place Environment by Scanning Electron Microscopy
size definition of respirable silicon carbide whiskers are
E 1435 Practice for Handling Densified Articles of Alumi-
covered by this practice.
num Oxide Reinforced with Silicon Carbide Whiskers
1.3 Mixtures of respirable and non-respirable whiskers or
E 1451 GuideforDisposalofWastesContainingRespirable
fibers, or both, are covered by this practice.
Silicon Carbide Whiskers
1.4 The information contained in this practice may be
E 1516 GuideforPackagingofUnboundRespirableSilicon
considered for use in a material safety data sheet (MSDS) for
Carbide Whiskers
silicon carbide whiskers.
E 1576 Guide for Medical Surveillance Program for Work-
1.5 Other materials may be present in the final product (for
ers with Occupational Exposure to Airborne Silicon Car-
example, crystalline silica); information specific to these addi-
bide Whiskers and Fibers
tional materials should be included in each manufacturer’s
E 1716 Guide for Selection and Use of Personal Protective
MSDS.
Equipment for Humans Working with Respirable Silicon
1.6 This standard does not purport to address all of the
Carbide Whiskers
safety concerns, if any, associated with its use. It is the
E 1717 Guide for Personnel Training for Health and Safety
responsibility of the user of this standard to establish appro-
Aspects of Working in Environments Containing Respi-
priate safety and health practices and determine the applica-
rable Silicon Carbide Whiskers
bility of regulatory limitations prior to use. For specific hazard
E 1718 Guide for Administrative and Engineering Controls
and precaution statements, see Sections 5, 7, 9, and 10.
for Silicon Carbide Whisker Work Areas
2. Referenced Documents 2.2 American National Standards Institute (ANSI) Stan-
dards:
2.1 ASTM Standards:
ANSI Z88.2—1992, Respiratory Protection
D 6056 Test Method for Determining the Concentration of
ANSI Z9.2—1979, Fundamentals Governing the Design
Airborne Single-Crystal Ceramic Whiskers in the Work-
and Operation of Local Exhaust Systems
place Environment by Transmission Electron Microscopy
2.3 Occupational Safety and Health Administration
(OSHA) Standard:
This practice is under the jurisdiction of ASTM Committee E34 on Occupa-
U.S. Code of Federal Regulations (CFR) 29 CFR 1910.134,
tional Health and Safety and is the direct responsibility of Subcommittee E34.70 on
Respiratory Protection
Single Crystal Ceramic Whiskers.
Current edition approved April 10, 1998. Published June 1998. Originally
published as E 1437 – 91. Last previous edition E 1437 – 91.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM 4th Floor, New York, NY 10036, http://www.ansi.org.
Standards volume information, refer to the standard’s Document Summary page on Available from Superintendent of Documents, U.S. Government Printing
the ASTM website. Office, Washington, DC 20402.
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E1437–98
3. Terminology carcinogenicity of ceramic fibers in experimental animals; no
data were available on the carcinogenicity of ceramic fibers to
3.1 Definitions:
humans.”)
3.1.1 aspect ratio, n—ratio of whisker length to whisker
diameter.
6. Physical/Chemical Characteristics
3.1.2 HEPA, n—disposable extended media dry-type, high-
6.1 The following data are relevant when preparing an
efficiency, particulate air filter with a particulate removal of no
MSDS for SiC whiskers:
less than 99.97 % for 0.3 µm diameter particles.
6.1.1 Boiling Point—Not applicable.
3.1.3 respirable silicon carbide whiskers, n—a crystalline 6.1.2 Vapor Pressure (mm Hg)—Not applicable.
silicon carbide fiber, approximately cylindrical in shape, with a 6.1.3 Vapor Density (AIR = 1)—Not applicable.
diameterlessthan3.0µmandanaspectratioequaltoorgreater 6.1.4 Solubility in Water—Insoluble.
than 5:1. 6.1.5 Relative Density (specific gravity)—3.2.
6.1.6 Oxidation—Occurs above 700°C.
6.1.7 Melting Point—Decomposes above 2500°C.
4. Significance and Use
6.1.8 pH—Not applicable.
4.1 Workers may be exposed to respirable SiC whiskers
6.1.9 Evaporation Rate (butyl acetate = 1)—Not appli-
during handling, processing, or use of SiC whiskers or pow-
cable.
dered blends containing SiC whiskers. Exposure may also
6.1.10 Appearance and Odor—Variable, typically green to
occur during (re)finishing of consolidated or densified articles
gray-green powder. No odor.
when respirable SiC whiskers are released.
4.2 This practice provides guidance for handling, process- 7. Fire and Explosion Hazard Data
ing, or use of SiC whiskers, either alone or combined with
7.1 The following data are relevant when preparing an
other materials. It is intended for use by health and safety
MSDS for SiC whiskers:
professionals in determining whether an excessive exposure
7.1.1 Flash Point—Non-flammable by conventional test
exists, in preparing procedures to establish a safe work
methods.
environment, and in preparing relevant documentation.
7.1.2 Flammable Limits—Non-flammable.
4.3 Users of this practice are directed to the following
7.1.3 Lower Explosive Limit (LEL)—Not applicable.
ASTM standards as supplemental information: Test Methods
7.1.4 Upper Explosive Limit (UEL)—Not applicable.
D 6056, D 6057, D 6058, and D 6059; Practice E 1435; and
7.1.5 Extinguishing Media—Use extinguishing media ap-
Guides E 1451, E 1516, E 1576, E 1716, E 1717, and E 1718.
propriate for the surrounding materials.
7.1.6 Special Fire Fighting Procedures—Avoid actions that
5. Hazardous Ingredients/Identity Information
would cause whiskers to become airborne. Wear pressure-
demand, self-contained breathing apparatus and full fire fight-
5.1 Hazardous Ingredients (specific chemical identity com-
ing protective clothing.
mon name(s))—Silicon carbide whiskers, an acicular form of
7.1.7 Unusual Fire and Explosion Hazards—Negligible fire
silicon carbide, which is Chemical Abstract Service (CAS)
and explosion hazard when whiskers alone are exposed to heat
409-21-2.ACASnumberspecifictoSiCwhiskershasnotbeen
and flame.
assigned. OSHA Permissible Exposure Limits (PELs) for SiC
NOTE 1—This section is applicable
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