Calcium oxide

Synonyms & Trade Names
Burned lime, Burnt lime, Lime, Pebble lime, Quick lime, Unslaked lime
CAS No.
1305-78-8
RTECS No.
DOT ID & Guide
1910 157
Formula
CaO
Conversion
IDLH
25 mg/m3
See: 1305788
Exposure Limits
NIOSH REL
TWA 2 mg/m3
OSHA 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 Weight
56.1
Boiling Point
5162°F
Melting Point
4662°F
Solubility
Reacts
Vapor Pressure
0 mmHg (approx)
Ionization Potential
NA
Specific Gravity
3.34
Flash Point
NA
Upper Exposive Limit
NA
Lower Explosive Limit
NA
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 17, 2018