CHROMIUM TRIOXIDE, ANHYDROUS
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The
Chemical Identifier fields
include common identification numbers, the
NFPA diamond
U.S. Department of Transportation hazard labels, and a general
description of the chemical. The information in CAMEO Chemicals comes
from a variety of
data sources.
| CAS Number | UN/NA Number |
|---|---|
|
|
| DOT Hazard Label | USCG CHRIS Code |
|
|
| NIOSH Pocket Guide | International Chem Safety Card |
Chromic acid and chromates
|
NFPA 704
| Diamond | Hazard | Value | Description | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Health
|
3 | Can cause serious or permanent injury. | |||||||||
Flammability
|
0 | Will not burn under typical fire conditions. | ||||||||||
Instability
|
1 | Normally stable but can become unstable at elevated temperatures and pressures. | ||||||||||
Special
|
OX | Possesses oxidizing properties. |
(NFPA, 2010)
General Description
A dark purplish red solid. Under prolonged exposure to fire or heat the containers may explode. Highly toxic. A confirmed human carcinogen.
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The
Hazard fields
include
special hazard alerts
air and water
reactions, fire hazards, health hazards, a reactivity profile, and
details about
reactive groups assignments
and
potentially incompatible absorbents.
The information in CAMEO Chemicals comes from a variety of
data sources.
Reactivity Alerts
- Strong Oxidizing Agent
- Water-Reactive
Air & Water Reactions
Deliquescent. Water soluble, giving acidic solutions.
Fire Hazard
Behavior in Fire: Containers may explode (USCG, 1999)
Health Hazard
Very irritating to eyes and respiratory tract. Ingestion causes severe gastrointestinal symptoms. Contact with eyes or skin causes burns; prolonged contact produces dermatitis ("chrome sores"). (USCG, 1999)
Reactivity Profile
CHROMIUM TRIOXIDE is a powerful oxidizing agent. Can react violently upon contact with reducing reagents, including organic matter, leading to ignition or explosion. Dangerously reactive with acetone, alcohols, alkali metals (sodium, potassium), ammonia, arsenic, dimethylformamide, hydrogen sulfide, phosphorus, peroxyformic acid, pyridine, selenium, sulfur, and many other chemicals [Sax, 9th ed., 1996, p. 852]. Noncombustible but can accelerate the burning of combustible materials. Sufficient heat may be generated from the reaction with combustible materials to ignite the mass. Aqueous solutions corrode many metals rapidly. Often mixed with sulfuric acid to make "cleaning solution" for glass. Used cleaning solution in closed bottles may explode due to the build up of gaseous carbon dioxide arising from oxidation of organic impurities [Bryson, W. R., Chem. Brit., 1975, 11, p. 377].
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents
Use caution: Liquids with this reactive group classification have been known to react with the absorbents listed below. More info about absorbents, including situations to watch out for...
- Cellulose-Based Absorbents
- Mineral-Based & Clay-Based Absorbents
- Expanded Polymeric Absorbents
- Dirt/Earth
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The
Response Recommendation fields
include isolation and evacuation distances, as well as recommendations for
firefighting, non-fire response, protective clothing, and first aid. The
information in CAMEO Chemicals comes from a variety of
data sources.
Isolation and Evacuation
Excerpt from ERG Guide 141 [Oxidizers - Toxic]:
IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.
LARGE SPILL: Consider initial downwind evacuation for at least 100 meters (330 feet).
FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.
LARGE SPILL: Consider initial downwind evacuation for at least 100 meters (330 feet).
FIRE: If tank, rail car or tank truck is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2020)
Firefighting
Excerpt from ERG Guide 141 [Oxidizers - Toxic]:
SMALL FIRE: Use water. Do not use dry chemicals or foams. CO2 or Halon® may provide limited control.
LARGE FIRE: Flood fire area with water from a distance. Do not move cargo or vehicle if cargo has been exposed to heat. If it can be done safely, move undamaged containers away from the area around the fire.
FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
SMALL FIRE: Use water. Do not use dry chemicals or foams. CO2 or Halon® may provide limited control.
LARGE FIRE: Flood fire area with water from a distance. Do not move cargo or vehicle if cargo has been exposed to heat. If it can be done safely, move undamaged containers away from the area around the fire.
FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Cool containers with flooding quantities of water until well after fire is out. ALWAYS stay away from tanks engulfed in fire. For massive fire, use unmanned master stream devices or monitor nozzles; if this is impossible, withdraw from area and let fire burn. (ERG, 2020)
Non-Fire Response
Excerpt from ERG Guide 141 [Oxidizers - Toxic]:
Keep combustibles (wood, paper, oil, etc.) away from spilled material. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk.
SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area.
LARGE SPILL: Dike far ahead of spill for later disposal. (ERG, 2020)
Keep combustibles (wood, paper, oil, etc.) away from spilled material. Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk.
SMALL DRY SPILL: With clean shovel, place material into clean, dry container and cover loosely; move containers from spill area.
LARGE SPILL: Dike far ahead of spill for later disposal. (ERG, 2020)
Protective Clothing
Goggles and respirator. (Special chromic acid filters are available for respirators to prevent inhalation of dust or mist.) (USCG, 1999)
DuPont Tychem® Suit Fabrics
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Tychem® Fabric Legend
| QS = Tychem 2000 SFR |
| QC = Tychem 2000 |
| SL = Tychem 4000 |
| C3 = Tychem 5000 |
| TF = Tychem 6000 |
| TP = Tychem 6000 FR |
| RC = Tychem RESPONDER® CSM |
| TK = Tychem 10000 |
| RF = Tychem 10000 FR |
Testing Details
The fabric permeation data was generated for DuPont by a third party
laboratory. Permeation data for industrial chemicals is obtained per
ASTM F739. Normalized breakthrough times (the time at which the
permeation rate exceeds 0.1 μg/cm2/min) are reported in minutes. All
chemicals have been tested between approximately 20°C and 27°C unless
otherwise stated. All chemicals have been tested at a concentration of
greater than 95% unless otherwise stated.
Chemical warfare agents (Lewisite, Sarin, Soman, Sulfur Mustard, Tabun
and VX Nerve Agent) have been tested at 22°C and 50% relative humidity
per military standard MIL-STD-282. "Breakthrough time" for chemical
warfare agents is defined as the time when the cumulative mass which
permeated through the fabric exceeds the limit in MIL-STD-282 [either
1.25 or 4.0 μg/cm2].
A Caution from DuPont
This information is based upon technical data that DuPont believes to
be reliable on the date issued. It is subject to revision as additional
knowledge and experience are gained. The information reflects
laboratory performance of fabrics, not complete garments, under
controlled conditions. It is intended for informational use by persons
having technical skill for evaluation under their specific end-use
conditions, at their own discretion and risk. It is the user's
responsibility to determine the level of toxicity and the proper
personal protective equipment needed. Anyone intending to use this
information should first verify that the garment selected is suitable
for the intended use. In many cases, seams and closures have shorter
breakthrough times and higher permeation rates than the fabric. If
fabric becomes torn,abraded or punctured, or if seams or closures fail,
or if attached gloves, visors, etc. are damaged, end user should
discontinue use of garment to avoid potential exposure to chemical.
Since conditions of use are outside our control, DuPont makes no
warranties, express or implied, including, without limitation, no
warranties of merchantability or fitness for a particular use and
assume no liability in connection with any use of this information.
This information is not intended as a license to operate under or a
recommendation to infringe any patent, trademark or technical
information of DuPont or others covering any material or its use.
| Chemical | CAS Number | State | QS | QC | SL | C3 | TF | TP | RC | TK | RF |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Chromic acid (CrO3) (44.9%) | 1333-82-0 | Liquid | >480 | >480 | >480 | >480 | >480 | >480 |
> indicates greater than.
Special Warning from DuPont: Tychem® and Tyvek® fabrics should not be used around heat, flames, sparks or in potentially flammable or explosive environments. Only...
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...Tychem® ThermoPro, Tychem® Reflector® and Tychem® TK styles 600T/601T
(with aluminized outer suit) garments are designed and tested to help
reduce burn injury during escape from a flash fire. Users of Tychem®
ThermoPro, Tychem® Reflector® and Tychem® TK styles 600T/601T (with
aluminized outer suit) garments should not knowingly enter an explosive
environment. Tychem® garments with attached socks must be worn inside
protective outer footwear and are not suitable as outer footwear. These
attached socks do not have adequate durability or slip resistance to be
worn as the outer foot covering.
(DuPont, 2023)
First Aid
EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.
SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas.
INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.
INGESTION: Some heavy metals are VERY TOXIC POISONS, especially if their salts are very soluble in water (e.g., lead, chromium, mercury, bismuth, osmium, and arsenic). IMMEDIATELY call a hospital or poison control center and locate activated charcoal, egg whites, or milk in case the medical advisor recommends administering one of them. Also locate Ipecac syrup or a glass of salt water in case the medical advisor recommends inducing vomiting. Usually, this is NOT RECOMMENDED outside of a physician's care. If advice from a physician is not readily available and the victim is conscious and not convulsing, give the victim a glass of activated charcoal slurry in water or, if this is not available, a glass of milk, or beaten egg whites and IMMEDIATELY transport victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, assure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital.
OTHER: Since this chemical is a known or suspected carcinogen you should contact a physician for advice regarding the possible long term health effects and potential recommendation for medical monitoring. Recommendations from the physician will depend upon the specific compound, its chemical, physical and toxicity properties, the exposure level, length of exposure, and the route of exposure. (NTP, 1992)
SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas.
INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.
INGESTION: Some heavy metals are VERY TOXIC POISONS, especially if their salts are very soluble in water (e.g., lead, chromium, mercury, bismuth, osmium, and arsenic). IMMEDIATELY call a hospital or poison control center and locate activated charcoal, egg whites, or milk in case the medical advisor recommends administering one of them. Also locate Ipecac syrup or a glass of salt water in case the medical advisor recommends inducing vomiting. Usually, this is NOT RECOMMENDED outside of a physician's care. If advice from a physician is not readily available and the victim is conscious and not convulsing, give the victim a glass of activated charcoal slurry in water or, if this is not available, a glass of milk, or beaten egg whites and IMMEDIATELY transport victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, assure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital.
OTHER: Since this chemical is a known or suspected carcinogen you should contact a physician for advice regarding the possible long term health effects and potential recommendation for medical monitoring. Recommendations from the physician will depend upon the specific compound, its chemical, physical and toxicity properties, the exposure level, length of exposure, and the route of exposure. (NTP, 1992)
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The
Physical Property fields
include properties such as vapor pressure and
boiling point, as well as explosive limits and
toxic exposure thresholds
The information in CAMEO Chemicals comes from a variety of
data sources.
Note: For Vapor Density and Specific Gravity, comparing the value to 1.0 can tell you if the chemical will likely sink/rise in air or sink/float in fresh water (respectively). Short phrases have been added to those values below as an aid. However, make sure to also consider the circumstances of a release. The Vapor Density comparisons are only valid when the gas escaping is at the same temperature as the surrounding air itself. If the chemical is escaping from a container where it was pressurized or refrigerated, it may first escape and behave as a heavy gas and sink in the air (even if it has a Vapor Density value less than 1). Also, the Specific Gravity comparisons are for fresh water (density 1.0 g/mL). If your spill is in salt water (density about 1.027 g/mL), you need to adjust the point of comparison. There are some chemicals that will sink in fresh water and float in salt water.
Note: For Vapor Density and Specific Gravity, comparing the value to 1.0 can tell you if the chemical will likely sink/rise in air or sink/float in fresh water (respectively). Short phrases have been added to those values below as an aid. However, make sure to also consider the circumstances of a release. The Vapor Density comparisons are only valid when the gas escaping is at the same temperature as the surrounding air itself. If the chemical is escaping from a container where it was pressurized or refrigerated, it may first escape and behave as a heavy gas and sink in the air (even if it has a Vapor Density value less than 1). Also, the Specific Gravity comparisons are for fresh water (density 1.0 g/mL). If your spill is in salt water (density about 1.027 g/mL), you need to adjust the point of comparison. There are some chemicals that will sink in fresh water and float in salt water.
| Chemical Formula: |
|
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature:
May ignite organic materials on contact.
(USCG, 1999)
Melting Point:
385°F
(NTP, 1992)
Vapor Pressure:
Very low
(NIOSH, 2023)
Vapor Density (Relative to Air): data unavailable
Specific Gravity:
2.7
(NTP, 1992)
- Denser than water; will sink
Boiling Point:
482°F
at 760 mmHg
(decomposes)
(NTP, 1992)
Molecular Weight:
100
(NTP, 1992)
Water Solubility:
Very soluble
(NTP, 1992)
Ionization Energy/Potential: data unavailable
IDLH:
15 mg Cr(VI)/m3
; A potential occupational carcinogen.
(NIOSH, 2023)
AEGLs (Acute Exposure Guideline Levels)
No AEGL information available.ERPGs (Emergency Response Planning Guidelines)
No ERPG information available.PACs (Protective Action Criteria)
| Chemical | PAC-1 | PAC-2 | PAC-3 |
|---|---|---|---|
| Chromic trioxide; (Chromium(VI) oxide (1:3)) (1333-82-0) | 0.29 mg/m3 | 5 mg/m3 | 30 mg/m3 |
(DOE, 2018)
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The
Regulatory Information fields
include information from
the U.S. Environmental Protection Agency's Title III Consolidated List of
Lists,
the U.S. Cybersecurity and Infrastructure Security Agency's Chemical Facility
Anti-Terrorism Standards,
and the U.S. Occupational Safety and Health Administration's
Process Safety Management of Highly Hazardous Chemicals Standard List
(see more about these
data sources).
EPA Consolidated List of Lists
| Regulatory Name | CAS Number/ 313 Category Code |
EPCRA 302 EHS TPQ |
EPCRA 304 EHS RQ |
CERCLA RQ | EPCRA 313 TRI |
RCRA Code |
CAA 112(r) RMP TQ |
|---|---|---|---|---|---|---|---|
| Chromium Compounds | N090 | & | 313 |
- & indicates that no RQ is assigned to this generic or broad class, although the class is a CERCLA hazardous substance. See 50 Federal Register 13456 (April 4, 1985).
(EPA List of Lists, 2022)
CISA Chemical Facility Anti-Terrorism Standards (CFATS)
No regulatory information available.OSHA Process Safety Management (PSM) Standard List
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This section provides a listing of alternate names for this chemical,
including trade names and synonyms.
- CHROMIA (CRO3)
- CHROMIC ACID (CRO3): CHROMIC ANHYDRIDE
- CHROMIC ANHYDRIDE
- CHROMIC OXIDE
- CHROMIC TRIOXIDE
- CHROMIUM (6+) TRIOXIDE
- CHROMIUM OXIDE
- CHROMIUM OXIDE (CR4O12)
- CHROMIUM OXIDE [CRO3]
- CHROMIUM TRIOXIDE
- CHROMIUM TRIOXIDE, ANHYDROUS
- CHROMIUM TRIOXIDE, [ANHYDROUS]
- CHROMIUM VI OXIDE
- CHROMIUM(VI) OXIDE
- CHROMIUM(VI) OXIDE (1:3)
- MONOCHROMIUM OXIDE
- MONOCHROMIUM TRIOXIDE
- PURATRONIC
Version 3.0.0