Chromium metal

Synonyms & Trade Names
Chrome, Chromium
CAS No.
7440-47-3
RTECS No.
DOT ID & Guide
Formula
Cr
Conversion
IDLH
250 mg/m3 (as Cr)
See: 7440473
Exposure Limits
NIOSH REL
TWA 0.5 mg/m3 See Appendix C
OSHA PEL
TWA 1 mg/m3 See Appendix C [*Note: The PEL also applies to insoluble chromium salts.]
Measurement Methods
NIOSH 7024 , 7300 , 7301 , 7303 , 9102;
OSHA ID121 , ID125G
See: NMAM or OSHA Methods
Physical Description
Blue-white to steel-gray, lustrous, brittle, hard, odorless solid.
Molecular Weight
52.0
Boiling Point
4788°F
Melting Point
3452°F
Solubility
Insoluble
Vapor Pressure
0 mmHg (approx)
Ionization Potential
NA
Specific Gravity
7.14
Flash Point
NA
Upper Explosive Limit
NA
Lower Explosive Limit
NA
Noncombustible Solid in bulk form, but finely divided dust burns rapidly if heated in a flame.
Incompatibilities & Reactivities
Strong oxidizers (such as hydrogen peroxide), alkalis
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation eyes, skin; lung fibrosis (histologic)
Target Organs
Eyes, skin, 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)
Eye:Irrigate immediately
Skin:Soap wash
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH

Up to 2.5 mg/m3:
(APF = 5) Any quarter-mask respirator.
Click here for information on selection of N, R, or P filters.*

Up to 5 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 12.5 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 25 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 250 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: 0029
Page last reviewed: October 30, 2019