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Chemical Datasheet

ALUMINUM POWDER, PYROPHORIC

4.2 - Spontaneously combustible

Chemical Identifiers

CAS Number UN/NA Number DOT Hazard Label USCG CHRIS Code
  • 7429-90-5
  • 1383
  • Spontaneously Combustible
none
NIOSH Pocket Guide International Chem Safety Card
Aluminum (pyro powders and welding fumes, as Al)
  • ALUMINIUM POWDER
NFPA 704
Diamond Hazard Value Description
3
0 1
Blue Health 0 No hazard beyond that of ordinary combustible material.
Red Flammability 3 Can be ignited under almost all ambient temperature conditions.
Yellow Instability 1 Normally stable but can become unstable at elevated temperatures and pressures.
White Special
(NFPA, 2010)
General Description
A light gray or silvery colored powdered metal.

Hazards

Reactivity Alerts
Air & Water Reactions
Highly flammable. Ignites spontaneously in air. Reacts with water to generate flammable gaseous hydrogen and heat.
Fire Hazard
Excerpt from 135 Polymerizable warning [Substances - Spontaneously Combustible]:

Flammable/combustible material. May ignite on contact with moist air or moisture. May burn rapidly with flare-burning effect. Some react vigorously or explosively on contact with water. Some may decompose explosively when heated or involved in a fire. May re-ignite after fire is extinguished. Runoff may create fire or explosion hazard. Containers may explode when heated. (ERG, 2020)
Health Hazard
Excerpt from 135 Polymerizable warning [Substances - Spontaneously Combustible]:

Fire will produce irritating, corrosive and/or toxic gases. Inhalation of decomposition products may cause severe injury or death. Contact with substance may cause severe burns to skin and eyes. Runoff from fire control or dilution water may cause environmental contamination. CAUTION: Pentaborane (UN1380) is highly toxic and may be fatal if inhaled, ingested or absorbed through skin. (ERG, 2020)
Reactivity Profile
ALUMINUM POWDER, PYROPHORIC is a reducing agent. Reacts very exothermically when mixed with metal oxides and ignited or heated (thermite process). Reacts explosively when mixed with copper oxides and heated [Mellor 5:217-19 1946-47]. Reacts with metal salts, mercury and mercury compounds, nitrates, sulfates, halogens, and halogenated hydrocarbons to form compounds that are sensitive to mechanical shock [Handling Chemicals Safely 1980. p. 135]. Mixtures with ammonium nitrate are used as an explosive. A mixture with powdered ammonium persulfate and water may explode [NFPA 491M 1991]. Heating with bismuth trioxide leads to an explosively violent reaction [Mellor 9:649 1946-47]. Mixtures with finely divided bromates (also chlorates and iodates) of barium, calcium, magnesium, potassium, sodium or zinc can explode by heat, percussion, and friction [Mellor 2:310 1946-47]. Burns in the vapor of carbon disulfide, in sulfur dioxide, sulfur dichloride, nitrous oxide, nitric oxide, or nitrogen peroxide [Mellor 5:209-212 1946-47]. A mixture with carbon tetrachloride exploded when heated to 153°C and also by impact [Chem. Eng. News 32:258 (1954); UL Bull. Research 34 (1945); ASESB Pot. Incid. 39 (1968)]. Mixing with chlorine trifluoride in the presence of carbon results in a violent reaction [Mellor 2 Supp. 1: 1956]. Ignites in close contact with iodine. Three industrial explosions involving a photoflash composition containing potassium perchlorate with aluminum and magnesium powder have occurred [ACS 146:210 1945; NFPA 491M 1991]. React with methyl chloride in the presence of small amounts of aluminum chloride to give flammable trimethylaluminum. Gives a detonable mixture with liquid oxygen [NFPA 491M 1991]. The reaction with silver chloride, once started, proceeds with explosive violence [Mellor 3:402 1946-47]. In an industrial accident, the accidental addition of water to a solid mixture of sodium hydrosulfite and powdered aluminum caused the generation of SO2, heat and more water. The aluminum powder reacted with the water and other reactants leading to an explosion that killed five workers [Case Study, Accident Investigation: Napp Technologies, 14th International Hazardous Material Spills Conference]. Particles can become electrostatically charged if swirled, transported by pneumatic means or poured.
Belongs to the Following Reactive Group(s)
Potentially Incompatible Absorbents

No information available.

Response Recommendations

Isolation and Evacuation
Excerpt from 135 Polymerizable warning [Substances - Spontaneously Combustible]:

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 the immediate precautionary measure distance, in the downwind direction, as necessary.

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 135 Polymerizable warning [Substances - Spontaneously Combustible]:

DO NOT USE WATER, CO2 OR FOAM ON MATERIAL ITSELF. Some of these materials may react violently with water. CAUTION: For Xanthates, UN3342 and for Dithionite (Hydrosulfite/Hydrosulphite) UN1384, UN1923 and UN1929, USE FLOODING AMOUNTS OF WATER for SMALL AND LARGE fires to stop the reaction. Smothering will not work for these materials, they do not need air to burn.

SMALL FIRE: Dry chemical, soda ash, lime or DRY sand, EXCEPT for UN1384, UN1923, UN1929 and UN3342.

LARGE FIRE: DRY sand, dry chemical, soda ash or lime EXCEPT for UN1384, UN1923, UN1929 and UN3342, or withdraw from area and let fire burn. CAUTION: UN3342 when flooded with water will continue to evolve flammable Carbon disulfide/Carbon disulphide vapors. 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. Do not get water inside containers or in contact with substance. 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, 2020)
Non-Fire Response
Excerpt from 135 Polymerizable warning [Substances - Spontaneously Combustible]:

ELIMINATE all ignition sources (no smoking, flares, sparks or flames) from immediate area. Do not touch or walk through spilled material. Stop leak if you can do it without risk.

SMALL SPILL: CAUTION: For spills of Xanthates, UN3342 and for Dithionite (Hydrosulfite/Hydrosulphite), UN1384, UN1923 and UN1929, dissolve in 5 parts water and collect for proper disposal. CAUTION: UN3342 when flooded with water will continue to evolve flammable Carbon disulfide/Carbon disulphide vapors. Cover with DRY earth, DRY sand or other non-combustible material followed with plastic sheet to minimize spreading or contact with rain. Use clean, non-sparking tools to collect material and place it into loosely covered plastic containers for later disposal. Prevent entry into waterways, sewers, basements or confined areas. (ERG, 2020)
Protective Clothing
Excerpt from ERG Guide 135 [Substances - Spontaneously Combustible]:

Wear positive pressure self-contained breathing apparatus (SCBA). Wear chemical protective clothing that is specifically recommended by the manufacturer when there is NO RISK OF FIRE. Structural firefighters' protective clothing provides thermal protection but only limited chemical protection. (ERG, 2020)
DuPont Tychem® Suit Fabrics
No information available.
First Aid
Excerpt from 135 Polymerizable warning [Substances - Spontaneously Combustible]:

Call 911 or emergency medical service. Ensure that medical personnel are aware of the material(s) involved and take precautions to protect themselves. Move victim to fresh air if it can be done safely. Give artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult. Remove and isolate contaminated clothing and shoes. In case of contact with substance, immediately flush skin or eyes with running water for at least 20 minutes. Keep victim calm and warm. (ERG, 2020)

Physical Properties

Chemical Formula:
  • Al
Flash Point: data unavailable
Lower Explosive Limit (LEL): data unavailable
Upper Explosive Limit (UEL): data unavailable
Autoignition Temperature: data unavailable
Melting Point: data unavailable
Vapor Pressure: data unavailable
Vapor Density (Relative to Air): data unavailable
Specific Gravity: data unavailable
Boiling Point: data unavailable
Molecular Weight: data unavailable
Water Solubility: data unavailable
Ionization Energy/Potential: 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)

No PAC information available.

Regulatory Information

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
Aluminum (fume or dust) 7429-90-5 313

(EPA List of Lists, 2022)

CISA Chemical Facility Anti-Terrorism Standards (CFATS)

RELEASE THEFT SABOTAGE
Chemical of Interest CAS Number Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Min Conc STQ Security
Issue
Aluminum (powder) 7429-90-5 ACG 100 pounds EXP/IEDP

(CISA, 2007)

OSHA Process Safety Management (PSM) Standard List

No regulatory information available.

Alternate Chemical Names