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        Syndicate





Silica, crystalline (as respirable dust)																				Related Pages
Synonyms & Trade Names
			Cristobalite, Quartz, Tridymite, Tripoli
CAS No.
			14808-60-7
	RTECS No.
			VV7330000
	DOT ID & Guide

FormulaSiO2
	Conversion
	IDLH
			Ca [25 mg/m3 (cristobalite, tridymite); 50 mg/m3 (quartz, tripoli)]See: 14808607

Exposure Limits
			NIOSH RELCa TWA 0.05 mg/m3 See Appendix A
					OSHA PEL TWA 50 μg/m3 See Appendix G
	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.]													
										
Molecular Weight60.1	
	Boiling Point4046°F
	Melting Point3110°F
	SolubilityInsoluble
	Vapor Pressure0 mmHg (approx)
	Ionization PotentialNA											
Specific Gravity2.66	
	Flash PointNA
	Upper Explosive Limit?
	Lower Explosive Limit?
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
					  ICSC CARD: 0808

			
							

			Page last reviewed:  October 30, 2019						Content
							source: 	National Institute for Occupational Safety and Health NIOSH Pocket Guide to Chemical Hazards
Introduction
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Chemical Names, Synonyms and Trade Names
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Appendices
A – NIOSH Potential Occupational Carcinogens
B – Thirteen OSHA-Regulated Carcinogens
C – Supplementary Exposure Limits
D – Substances with No Established RELs
E – OSHA Respirator Requirements for Selected Chemicals
F – Miscellaneous Notes
G – 1989 Air Contaminants Update Project: Exposure Limits NOT in Effect
Type C & CE – Definitions for Type C and Type CE Respirators
Personal Protection and Sanitation Codes
First Aid Procedures Follow NIOSH Facebook
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