# NIOSH Pocket Guide to Chemical Hazards
Iron oxide dust and fume (as Fe) | CAS 1309-37-1
Fe2O3 | RTECS NO7400000 NO7525000 (fume)
Synonyms & Trade Names Ferric oxide, Iron(III) oxide | DOT ID & Guide 1376 135 (spent)
Exposure Limits | NIOSH REL: TWA 5 mg/m3
OSHA PEL: TWA 10 mg/m3
IDLH 2500 mg/m3 (as Fe) | Conversion
Physical Description Reddish-brown solid. [Note: Exposure to fume may occur during the arc-welding of iron.]
MW: 159.7 | BP: ? | MLT: 2664°F | Sol: Insoluble
VP: 0 mmHg (approx) | IP: NA |  | Sp.Gr: 5.24
Fl.P: NA | UEL: NA | LEL: NA |
Noncombustible Solid
Incompatibilities & Reactivities Calcium hypochlorite
Measurement Methods NIOSH 7300; OSHA ID121, ID125G
Personal Protection & Sanitation 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 NIOSH Up to 50 mg/m3: (APF = 10) Any dust, mist, and fume respirator/(APF = 10) Any supplied-air respirator Up to 125 mg/m3: (APF = 25) Any supplied-air respirator operated in a continuous-flow mode/(APF = 25) Any powered, air-purifying respirator with a dust, mist, and fume filter Up to 250 mg/m3: (APF = 50) Any air-purifying, full-facepiece respirator with a high-efficiency particulate filter/(APF = 50) Any supplied-air respirator that has a tight-fitting facepiece and is operated in a continuous-flow mode/(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 2500 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 a high-efficiency particulate filter/Any appropriate escape-type, self-contained breathing apparatus
Exposure Routes inhalation
Symptoms Benign pneumoconiosis with X-ray shadows indistinguishable from fibrotic pneumoconiosis (siderosis)
Target Organs respiratory system
See also: INTRODUCTION