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Calcium oxide																				Related Pages
Synonyms & Trade Names
			Burned lime, Burnt lime, Lime, Pebble lime, Quick lime, Unslaked lime
CAS No.
			1305-78-8
	RTECS No.
			EW3100000
	DOT ID & Guide
			1910 157

FormulaCaO
	Conversion
	IDLH
			25 mg/m3See: 1305788

Exposure Limits
			NIOSH RELTWA 2 mg/m3OSHA PEL TWA 5 mg/m3
	Measurement Methods
			**NIOSH** 7020 , 7303;**OSHA** ID121
					
					See: NMAM or OSHA Methods
										
Physical Description
			White or gray, odorless lumps or granular powder.													
										
Molecular Weight56.1	
	Boiling Point5162°F
	Melting Point4662°F
	SolubilityReacts
	Vapor Pressure0 mmHg (approx)
	Ionization PotentialNA											
Specific Gravity3.34	
	Flash PointNA
	Upper Explosive LimitNA
	Lower Explosive LimitNA
Noncombustible Solid, but will support combustion by liberation of oxygen.
Incompatibilities & Reactivities
			Water (liberates heat), fluorine, ethanol
					[Note: Reacts with water to form calcium hydroxide.]
Exposure Routes
			inhalation, ingestion, skin and/or eye contact
Symptoms
			irritation eyes, skin, upper resp tract; ulcer, perforation nasal septum; pneumonitis; dermatitis
Target Organs
			Eyes, skin, respiratory system
										
Personal Protection/Sanitation
			(See protection codes) **Skin:**Prevent skin contact
							**Eyes:**Prevent eye contact
							**Wash skin:**When contaminated/Daily
							**Remove:**When wet or contaminated
							**Change:**Daily
							**Provide:**Eyewash, Quick drench
	First Aid
			(See procedures)**Eye:**Irrigate immediately
							**Skin:**Water flush immediately
							**Breathing:**Respiratory support
							**Swallow:**Medical attention immediately
Respirator Recommendations
			**NIOSH****Up to 10 mg/m3**: (APF = 5) Any quarter-mask respirator. Click here for information on selection of N, R, or P filters.**Up to 20 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.(APF = 10) Any supplied-air respirator**Up to 25 mg/m3**: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter./(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 self-contained breathing apparatus with a full facepiece(APF = 50) Any supplied-air respirator with a full facepiece**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: 0409

			
							

			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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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
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