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Chemical Datasheet

SULFUR, MOLTEN

4.1 - Flammable solid 9 - Miscellaneous hazardous material
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
  • 7704-34-9
  • Flammable Solid (international)
  • Class 9 (domestic)
NFPA 704
Diamond Hazard Value Description
1
2 0
Blue Health 2 Can cause temporary incapacitation or residual injury.
Red Flammability 1 Must be preheated before ignition can occur.
Yellow Instability 0 Normally stable, even under fire conditions.
White Special
(NFPA, 2010)
General Description
A pale yellow crystalline solid with a faint odor of rotten eggs. Insoluble in water. A fire and explosion risk above 450° F. Transported as a yellow to red liquid. Handled at elevated temperature (typically 290°F) to prevent solidification and makes transfers easier. Hot enough that plastic or rubber may melt or lose strength. Causes thermal burns to skin on contact. Cools rapidly and solidifies if released. Equipment designed to protect against ordinary chemical exposure is ineffective against the thermal hazard. Exercise caution walking on the surface of a spill to avoid breakthrough into pockets of molten sulfur below the crust. Do not attempt to remove sulfur impregnated clothing because of the danger of tearing flesh if a burn has resulted. May be irritatin to skin, eyes and mucous membranes. Used in sulfuric acid production, petroleum refining, and pulp and paper manufacturing.

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
Flammable. Insoluble in water.
Fire Hazard
Special Hazards of Combustion Products: Produces toxic sulfur dioxide gas.

Behavior in Fire: Burns with a pale blue flame that may be difficult to see in daylight. (USCG, 1999)
Health Hazard
Can cause eye irritation; may rarely irritate skin. If recovered sulfur, refer to hydrogen sulfide.* (USCG, 1999)
Reactivity Profile
SULFUR reacts violently with strong oxidizing agents causing fire and explosion hazards [Handling Chemicals Safely 1980 p. 871]. Reacts with iron to give pyrophoric compounds. Attacks copper, silver and mercury. Reacts with bromine trifluoride, even at 10°C [Mellor 2:113. 1946-47]. Ignites in fluorine gas at ordinary temperatures [Mellor 2:11-13 1946-47]. Reacts to incandescence with heated with thorium [Mellor 7:208 1946-47]. Can react with ammonia to form explosive sulfur nitride. Reacts with calcium phosphide incandescently at about 300°C. Reacts violently with phosphorus trioxide [Chem. Eng. News 27:2144 1949]. Mixtures with ammonium nitrate or with metal powders can be exploded by shock [Kirk and Othmer 8:644]. Combinations of finely divided sulfur with finely divided bromates, chlorates, or iodates of barium, calcium, magnesium, potassium, sodium, or zinc can explode with heat, friction, percussion, and sometimes light [Mellor 2 Supp.1:763. 1956]. A mixture with barium carbide heated to 150°C becomes incandescent. Reacts incandescently with calcium carbide or strontium carbide at 500°C. Attacks heated lithium, or heated selenium carbide with incandescence [Mellor 5:862 1946-47]. Reacts explosively if warmed with powdered zinc [Mellor 4:476. 1946-47]. Reacts vigorously with tin [Mellor 7:328. 1946-47]. A mixture with potassium nitrate and arsenic trisulfide is a known pyrotechnic formulation [Ellern 1968 p. 135]. Mixtures with any perchlorate can explode on impact [ACS 146:211-212]. A mixture of damp sulfur and calcium hypochlorite produces a brilliant crimson flash with scatter of molten sulfur [Chem. Eng. News 46(28):9 1968]. Takes fire spontaneously in chlorine dioxide and may produce an explosion [Mellor 2:289 (1946-47)]. Ignites if heated with chromic anhydride ignite and can explode, [Mellor 10:102 (1946-47)]. Even small percentages of hydrocarbons in contact with molten sulfur generate hydrogen sulfide and carbon disulfide, which may accumulate in explosive concentrations. Sulfur reacts with Group I metal nitrides to form flammable mixtures, evolving flammable and toxic NH3 and H2S gases if water is present. (Mellor, 1940, Vol. 8, 99).
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

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 133 [Flammable Solids]:

As an immediate precautionary measure, isolate spill or leak area for at least 25 meters (75 feet) in all directions.

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, 2012)
Firefighting
Excerpt from GUIDE 133 [Flammable Solids]:

SMALL FIRE: Dry chemical, CO2, sand, earth, water spray or regular foam.

LARGE FIRE: Water spray, fog or regular foam. Move containers from fire area if you can do it without risk. Fire Involving Metal Pigments or Pastes (e.g. "Aluminum Paste") Aluminum Paste fires should be treated as a combustible metal fire. Use DRY sand, graphite powder, dry sodium chloride based extinguishers, G-1® or Met-L-X® powder. Also, see GUIDE 170.

FIRE INVOLVING TANKS OR CAR/TRAILER LOADS: Cool containers with flooding quantities of water until well after fire is out. For massive fire, use unmanned hose holders or monitor nozzles; if this is impossible, withdraw from area and let fire burn. 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 133 [Flammable Solids]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames in immediate area). Do not touch or walk through spilled material.

SMALL DRY SPILL: With clean shovel place material into clean, dry container and cover loosely; move containers from spill area.

LARGE SPILL: Wet down with water and dike for later disposal. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2012)
Protective Clothing
Safety goggles with side shields; approved respirator; heat-resistant gloves; leather heat-resistant clothing. If recovered sulfur, refer to hydrogen sulfide.* (USCG, 1999)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
EYES: wash eyes carefully for at least 15 min.

SKIN: Treat molten sulfur burns with petroleum jelly or mineral oil. If recovered sulfur, treat as for hydrogen sulfide.* (USCG, 1999)

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:
  • S
Flash Point: 405 ° F (USCG, 1999)
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: 450 ° F (USCG, 1999)
Melting Point: 251 ° F (USCG, 1999)
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: 1.8 at 248.0 ° F (USCG, 1999)
Boiling Point: 832.3 ° F at 760.0 mm Hg (USCG, 1999)
Molecular Weight: 256.51 (USCG, 1999)
Water Solubility: data unavailable
IDLH: data unavailable

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
Sulfur (7704-34-9) 2.8 mg/m3 31 mg/m3 190 mg/m3
(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.
No regulatory information available.

Alternate Chemical Names

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