Document vB1rQja4gjYemO13mzgoEbyB9
PLAINTIFF'S EXHIBIT
TLVs Threshold Limit Values
for Chemical Substances
and Physical Agents
in the Workroom Environment
with Intended Changes
for
1976
CBY 3102501
C 000160 LAM022070
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SIUCA. SrOj Crystalline
Quartz
MINERAL OUSTS
TLV in mppcf": 300"
% quartz * 10 TLV for respirable dust mg/m3:
10 mg/m3*1
in
% Respirable quartz + 2 TLV for total dust." respirable and nonrespirable:
30 mg/m3
% quartz + 3
Cristobalite.............Use one-half the value calculated
from the count or mass formulae
for quartz.
Tridymite
Use one-half the value calculated
from formulae for quartz.
Silica, fused
Use quartz formulae.
Tripoli
Use respirable0' mass quartz for
mula
` 'Amorphous.....................................................20 mppcf"
SILICATES (< 1% quartz) Asbestos, all forms*
Graphite (natural) Mica Mineral wool fiber Perlite Portland Cement Soapstone Talc (nonasbestiform) Talc (fibrous) use Asbestos limit. Tremolite, see Asbestos.
5 fibers/cc > 5/im in length"': Ala 15 mppcf 20 mppcf 10 mg/m3 30 mppcf 30 mppcf 20 mppcf 20 mppcf
`A more stringent TLV for croadolite may be required l). n| See p 33 "See Notee of Intended Changes
32
COAL DUST
2 mg/m3 (respirable dust fraction < 5% quartz). If > 5% quartz, use respirable mass formula.
NUISANCE PARTICULATES
(see Appendix E)
30 mppcf or 10 mg/m3" of total dust < 1 % quartz, or. 5 mg/m3 respirable dust.
Conversion factors: mppcf x 35.3 = Million particles per cubic meter = particles per c.c.
i) Millions of particles per cubic foot of air. based on impinger samples counted by light-field technics.
j) The percentage of quartz in the formula is the amount determined from airborne samples, except in those instances in which other methods have been shown to be applicable.
k) Both concentration and percent quartz for the appli cation of this limit are to be determined from the fraction passing a size-selector with the following
charactenstics:
Aerodynamic Diameter (jun) (unit density sphere)
-s 2 2.5 3.5 5.0
10
% passing
selector 90 75 50 25 0
l) containing <1% quartz; if quartz content > 1%. use formulae for quartz.
m) Lint-free dust as measured by the vertical-elutriator. cotton-dust sampler described in the Transactions of the National Conference on Cotton Oust. Jr R Lynch, pg. 33, May 2, 1970.
n) As determined by the membrane filter method at 400-450X magnification (4 mm objective) phase con trast illumination.
o) Based on high volume' sampling. p) "Respirable" dust as defined by the British Medical
33
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CBY 3102502
C 000161
LAM022071