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Boron oxide

Synonyms & Trade Names
Boric anhydride, Boric oxide, Boron trioxide
CAS No.
1303-86-2
RTECS No.
ED7900000
DOT ID & Guide
Formula
B₂O₃
Conversion
IDLH
2000 mg/m3
See: 1303862
Exposure Limits
NIOSH REL
TWA 10 mg/m3
OSHA PEL
TWA 15 mg/m3 See Appendix G
Measurement Methods
NIOSH 0500
See: NMAM or OSHA Methods
Physical Description
Colorless, semitransparent lumps or hard, white, odorless crystals.
Molecular Weight
69.6
Boiling Point
3380°F
Melting Point
842°F
Solubility
3%
Vapor Pressure
0 mmHg (approx)
Ionization Potential
13.50 eV
Specific Gravity
2.46
Flash Point
NA
Upper Exposive Limit
NA
Lower Explosive Limit
NA
Noncombustible Solid
Incompatibilities & Reactivities
Water [Note: Reacts slowly with water to form boric acid.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin, respiratory system; cough; conjunctivitis; skin erythema (skin redness)
Target Organs
Eyes, skin, respiratory system
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:No recommendation
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Water flush promptly
Breathing:Fresh air
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH

Up to 50 mg/m3:
(APF = 5) Any quarter-mask respirator.
Click here for information on selection of N, R, or P filters.*

Up to 100 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 250 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.*

Up to 500 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*
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Up to 2000 mg/m3:
(APF = 2000) Any supplied-air respirator that has a full facepiece and is 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: 0836

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