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Chemical Datasheet

OSMIUM TETROXIDE

6.1 - Poisonous materials
Chemical Identifiers | Hazards | Response Recommendations | Physical Properties | Regulatory Information | Alternate Chemical Names

Chemical Identifiers

CAS Number - Chemical Abstracts Service registry number. Unique identification number assigned to this chemical by the American Chemical Society.

UN/NA Number - The United Nations-North America number (also called UN number or DOT number). 4-digit number identifying an individual chemical or group of chemicals with similar characteristics. Required on shipping papers; often shown on placards or labels. This numbering system was developed by the U.S. Department of Transportation, and then became the UN standard system for classifying hazardous materials.

DOT Hazard Label - U.S. Department of Transportation hazard warning label for the chemical (such as flammable liquid or corrosive). This label must be displayed on shipped packages, railroad tank cars, and tank trucks according to specifications described in 49 CFR 172.

CHRIS Code - 3-letter code used by the U.S. Coast Guard to identify individual chemicals included in its CHRIS (Chemical Hazards Response Information System) manual.

NFPA 704 - Text description of the diamond-shaped placard, which contains codes indicating the level of the chemical's health, flammability, and instability hazards, along with special hazards such as water- and air-reactivity. See a guide to the NFPA diamond.

General Description - Brief description of the chemical's general appearance, behavior, and hazardousness.

List of data sources.
CAS Number UN/NA Number DOT Hazard Label CHRIS Code
  • 20816-12-0
  • Poison
none
NFPA 704
data unavailable
General Description
A colorless or yellow solid with a pungent odor of chlorine. Begins to sublime below melting point. Soluble in alcohol. Toxic by inhalation and a strong irritant to the eyes and mucous membranes.

Hazards

Reactivity Alerts - Special alerts if the chemical is especially reactive (see list of reactivity alerts).

Air & Water Reactions - Special alerts if the chemical reacts with air, water, or moisture.

Fire Hazard - Description of the chemical's fire hazards (such as flammability, explosion risk, or byproducts that may evolve if the chemical is burned).

Health Hazard - Description of the chemical's health hazards (such as toxicity, flammability, or corrosivity).

Reactivity Profile - Description of the chemical's potential reactivity with other chemicals, air, and water. Also includes any other intrinsic reactive hazards (such as polymerizable or peroxidizable).

Reactive Groups - List of reactive groups that the chemical is assigned to, based on its known chemistry. Reactive groups are categories of chemicals that react in similar ways because their chemical structures are similar. Reactive groups are used to predict reactivity when you add a chemical to MyChemicals. Read more about reactive groups.

Potentially Incompatible Absorbents - Absorbents are products that can be used to soak up liquids from spills. However, some absorbents can react with particular chemicals (that is, they are incompatible), so caution should be used in selecting the correct absorbent for your situation. This section provides a list of potentially incompatible absorbents that have been known to react with liquids assigned to one or more of the reactive groups listed on this datasheet. Read more about absorbents, including situations to watch out for.

List of data sources.
Reactivity Alerts
Air & Water Reactions
Soluble in water.
Fire Hazard
Excerpt from GUIDE 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. For UN3171, if Lithium ion batteries are involved, also consult GUIDE 147. (ERG, 2012)
Health Hazard
Excerpt from GUIDE 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution. (ERG, 2012)
Reactivity Profile
OSMIUM TETROXIDE is incompatible with hydrochloric acid andeasily oxidized organic materials. Contact with other materials may cause fire. (NIOSH, 1997). Reacted explosively with 1-methylimidazole [J. Chem. Soc., Dalton Trans., 1979, 1084].
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...

Response Recommendations

Isolation and Evacuation - Isolation and evacuation distance recommendations from the Emergency Response Guidebook (ERG).

Firefighting - Response recommendations if the chemical is on fire (or near a fire).

Non-Fire Response - Response recommendations if the chemical isn't on fire (or near a fire).

Protective Clothing - Recommendations for protective gear.

Dupont Tychem® Suit Fabrics - A table of normalized breakthrough times for DuPont Tychem suit fabrics for the chemical, if available.

First Aid - Recommended first aid treatment for people exposed to the chemical.

List of data sources.
Isolation and Evacuation
Excerpt from GUIDE 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

As an 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.

SPILL: Increase, in the downwind direction, as necessary, the isolation distance shown above.

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, 2012)
Firefighting
Excerpt from GUIDE 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. Move containers from fire area if you can do it without risk. Dike fire-control water for later disposal; do not scatter the material.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Fight fire from maximum distance or use unmanned hose holders or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks engulfed in fire. (ERG, 2012)
Non-Fire Response
Excerpt from GUIDE 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). Do not touch damaged containers or spilled material unless wearing appropriate protective clothing. Stop leak if you can do it without risk. Prevent entry into waterways, sewers, basements or confined areas. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. DO NOT GET WATER INSIDE CONTAINERS. (ERG, 2012)
Protective Clothing
Skin: Wear appropriate personal protective clothing to prevent skin contact.

Eyes: Wear appropriate eye protection to prevent eye contact.

Wash skin: The worker should immediately wash the skin when it becomes contaminated.

Remove: Work clothing that becomes wet or significantly contaminated should be removed and replaced.

Change: Workers whose clothing may have become contaminated should change into uncontaminated clothing before leaving the work premise.

Provide: Eyewash fountains should be provided in areas where there is any possibility that workers could be exposed to the substance; this is irrespective of the recommendation involving the wearing of eye protection. (NIOSH, 2003)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Eye: If this chemical contacts the eyes, immediately wash the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately. Contact lenses should not be worn when working with this chemical.

Skin: If this chemical contacts the skin, immediately wash the contaminated skin with soap and water. If this chemical penetrates the clothing, immediately remove the clothing, wash the skin with soap and water, and get medical attention promptly.

Breathing: If a person breathes large amounts of this chemical, move the exposed person to fresh air at once. If breathing has stopped, perform mouth-to-mouth resuscitation. Keep the affected person warm and at rest. Get medical attention as soon as possible.

Swallow: If this chemical has been swallowed, get medical attention immediately. (NIOSH, 2003)

Physical Properties

This section contains physical properties, flammability limits, and toxic thresholds for this chemical (see definitions of each property). More property data is available for common chemicals.

See also the Levels of Concern guide for information on AEGLs, ERPGs, PACs, and IDLH values.

List of data sources.
Chemical Formula:
  • O4Os
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: 105 ° F (NIOSH, 2003)
Vapor Pressure: 7 mm Hg (NIOSH, 2003)
Vapor Density (Relative to Air): data unavailable
Specific Gravity: data unavailable
Boiling Point: 266 ° F at 760.0 mm Hg (NIOSH, 2003)
Molecular Weight: 254.2 (NIOSH, 2003)
Water Solubility: 6 % at 77° F (NIOSH, 2003)
IDLH: 1 mg/m3 (NIOSH, 2003)

AEGLs (Acute Exposure Guideline Levels)

Interim AEGLs for Osmium tetroxide (20816-12-0)
Exposure Period AEGL-1 AEGL-2 AEGL-3
10 minutes NR 0.015 ppm 5 ppm
30 minutes NR 0.011 ppm 5 ppm
60 minutes NR 0.0084 ppm 4 ppm
4 hours NR 0.0033 ppm 2.5 ppm
8 hours NR 0.0017 ppm 2 ppm
NR = Not recommended due to insufficient data.
(NAC/NRC, 2013)

ERPGs (Emergency Response Planning Guidelines)

No ERPG information available.

PACs (Protective Action Criteria)

Chemical PAC-1 PAC-2 PAC-3
Osmium tetroxide (20816-12-0) 0.0006 ppm 0.0084 ppm 4 ppm
(SCAPA, 2012)

Regulatory Information

This section contains regulatory information from the Title III Consolidated List of Lists (see details about each regulatory field).

List of data sources.
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
Osmium oxide OsO4 (T-4)- 20816-12-0 1000 X P087
Osmium tetroxide 20816-12-0 1000 313 P087

(EPA List of Lists, 2012)

Alternate Chemical Names

This section provides a listing of alternate names for this chemical, including trade names and synonyms.