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Magnesium oxide fume

Synonyms & Trade Names
Magnesia fume
CAS No.
1309-48-4
RTECS No.
DOT ID & Guide
Formula
MgO
Conversion
IDLH
750 mg/m3
See: 1309484
Exposure Limits
NIOSH REL
See Appendix D
OSHA PEL
TWA 15 mg/m3 See Appendix G
Measurement Methods
NIOSH 7300 , 7301 , 7303;
OSHA ID121
See: NMAM or OSHA Methods
Physical Description
Finely divided white particulate dispersed in air. [Note: Exposure may occur when magnesium is burned, thermally cut, or welded upon.]
Molecular Weight
40.3
Boiling Point
6512°F
Melting Point
5072°F
Solubility
(86°F): 0.009%
Vapor Pressure
0 mmHg (approx)
Ionization Potential
NA
Specific Gravity
3.58
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Noncombustible Solid
Incompatibilities & Reactivities
Chlorine trifluoride, phosphorus pentachloride
Exposure Routes
inhalation, skin and/or eye contact
Symptoms
irritation eyes, nose; metal fume fever: cough, chest pain, flu-like fever
Target Organs
Eyes, respiratory system
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)


Breathing:Respiratory support
Respirator Recommendations

OSHA

Up to 150 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 375 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 750 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

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: 0504   MEDICAL TESTS: 0251
Page last reviewed: October 30, 2019