# NIOSH Pocket Guide to Chemical Hazards
Tantalum (metal and oxide dust, as Ta) | CAS 7440-25-7 (metal)
Ta (metal) | RTECS WW5505000 (metal)
Synonyms & Trade Names Tantalum metal: Tantalum-181 Synonyms of other tantalum dusts (including oxide dusts) vary depending upon the specific compound. | DOT ID & Guide
Exposure Limits | NIOSH REL: TWA 5 mg/m3 ST 10 mg/m3
OSHA PEL: TWA 5 mg/m3
IDLH 2500 mg/m3 (as Ta) | Conversion
Physical Description Metal: Steel-blue to gray solid or black, odorless powder.
MW: 180.9 | BP: 9797°F | MLT: 5425°F | Sol: Insoluble
VP: 0 mmHg (approx) | IP: NA |  | Sp.Gr: 16.65 (metal) 14.40 (powder)
Fl.P: NA | UEL: NA | LEL: NA | MEC: <200 g/m3
Metal: Combustible Solid; powder ignites SPONTANEOUSLY in air.
Incompatibilities & Reactivities Strong oxidizers, bromine trifluoride, fluorine
Measurement Methods NIOSH 0500
Personal Protection & Sanitation Skin: No recommendation Eyes: No recommendation Wash skin: No recommendation Remove: No recommendation Change: No recommendation | First Aid (See procedures) Eye: Irrigate immediately Breathing: Respiratory support
Respirator Recommendations NIOSH/OSHA Up to 25 mg/m3: (APF = 5) Any dust and mist respirator^ Up to 50 mg/m3: (APF = 10) Any dust and mist respirator except single-use and quarter-mask respirators^/(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 and mist 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, skin and/or eye contact
Symptoms Irritation eyes, skin; in animals: pulmonary irritation
Target Organs Eyes, skin, respiratory system
See also: INTRODUCTION