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Silica, crystalline (as respirable dust)

Synonyms & Trade Names
Cristobalite, Quartz, Tridymite, Tripoli
CAS No.
14808-60-7
RTECS No.
VV7330000
DOT ID & Guide
Formula
SiO2
Conversion
IDLH
Ca [25 mg/m3 (cristobalite, tridymite); 50 mg/m3 (quartz, tripoli)]
See: 14808607
Exposure Limits
NIOSH REL
: Ca TWA 0.05 mg/m3 See Appendix A
OSHA PEL
†: See Appendix C (Mineral Dusts)
Measurement Methods

NIOSH 7500 , 7601 , 7602;
OSHA ID142
See: NMAM or OSHA Methods
Physical Description
Colorless, odorless solid. [Note: A component of many mineral dusts.]
MW:
60.1
BP:
4046°F		 MLT: 3110°F
Sol:
Insoluble
VP:
0 mmHg (approx)
IP:
NA
Sp.Gr:
2.66
Fl.P:
NA
UEL:
?
LEL:
?
Noncombustible solid
Incompatibilities & Reactivities
Powerful oxidizers: fluorine, chlorine trifluoride, manganese trioxide, oxygen difluoride, hydrogen peroxide, etc.; acetylene; ammonia
Exposure Routes
inhalation, skin and/or eye contact
Symptoms
Cough, dyspnea (breathing difficulty), wheezing; decreased pulmonary function, progressive resp symptoms (silicosis); irritation eyes; [potential occupational carcinogen]
Target Organs
Eyes, respiratory system
Cancer Site
[in animals: lung cancer]
Personal Protection/Sanitation
(See protection codes)
Skin: No recommendation
Eyes: No recommendation
Wash skin: No recommendation
Remove: No recommendation
Change: No recommendation
First Aid
(See procedures)
Eye: Irrigate immediately

Breathing: Fresh air
Respirator Recommendations

NIOSH

Up to 0.5 mg/m3:
(APF = 10) Any particulate respirator equipped with an N95, R95, or P95 filter (including N95, R95, and P95 filtering facepieces) except quarter-mask respirators. The following filters may also be used: N99, R99, P99, N100, R100, P100.
Click here for information on selection of N, R, or P filters.

Up to 1.25 mg/m3:
(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter.
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode

Up to 2.5 mg/m3:
(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
(APF = 50) Any powered, air-purifying respirator with a tight-fitting facepiece and a high-efficiency particulate filter

Up to 25 mg/m3:
(APF = 1000) Any supplied-air respirator operated in a pressure-demand or other positive-pressure mode

Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also: INTRODUCTION   See ICSC CARD: 0808
 

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