NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

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) See: IDLH INDEX
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
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
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 quarter-mask respirator. Click here for information on selection of N, R, or P filters.
Up to 50 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 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 125 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 250 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 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 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
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