TIME-WEIGHTED AVERAGE (TLV-TWA): 5 mg/m³ (pyro powder, as Al), 10 mg/m³ (metal dust)

TLV BASIS - CRITICAL EFFECT(S) : Lung (pyropowders); Irritation (metal dust)

NOTE: In many Canadian jurisdictions, exposure limits are similar to the ACGIH TLVs. Since the manner in which exposure limits are established, interpreted, and implemented can vary, obtain detailed information from the appropriate government agency in each jurisdiction.

Reactive flammable solid. Bulk aluminum powder or dust in contact with water may heat spontaneously. Moist, finely divided aluminum powder may ignite in air, with the formation of flammable hydrogen gas. The hazard increases as the aluminum particle size decreases. Contact of burning aluminum with water forms flammable hydrogen gas, an extremely dangerous explosion hazard, particularly if the fire is in a confined area. Bulk aluminum metal itself is not combustible.

Under certain conditions, a dust cloud of aluminum powder can explode when ignited by a spark or flame. When evaluating the explosion hazard of a specific process or sample of material, the important factors to consider include: particle size and shape, dust concentration, the nature of any impurities, oxygen concentration, humidity, and extent of containment. Explosions of aluminum dusts have occurred in industry.

IGNITION SENSITIVITY: 1.4 (aluminum, atomized); 7.3 (aluminum, flake)

EXPLOSION SEVERITY: 7.7 (aluminum, atomized); 10.2 (aluminum, flake)

The EXPLOSIBILITY INDEX is greater than 10 for both atomized and flake aluminum. This value indicates that a "severe" explosion could occur. This hazard rating index is calculated by multiplying the ignition sensitivity (ignition temperature, concentration, etc.) and the explosion severity (explosion pressure, rate of pressure rise).

MINIMUM IGNITION TEMPERATURE: 650 deg C (1202 deg F) (cloud); 760 deg C (1400 deg F) (layer) (aluminum, atomized); 610 deg C (1130 deg F) (cloud); 320-326 deg C (608-619 deg F) (layer) (aluminum, flake); 420 deg C (788 deg F) (aluminum, 6 µm)

MINIMUM CLOUD IGNITION ENERGY: 50 millijoules (mJ) (aluminum, atomized); 10 mJ (aluminum, flake); 13 mJ (aluminum, 6 µm); 28 mJ (aluminum, 17 µm)

MAXIMUM EXPLOSION PRESSURE: 579.2 kPa (84 psi) (aluminum, atomized); 875.7 kPa (127 psi or 8.8 bar) (aluminum, flake); 640 kPa (6.4 bar) (aluminum, 6 µm); 700 kPa (7.0 bar) (aluminum, 17 µm); 540 kPa (5.4 bar) (aluminum, 100 µm)

MAXIMUM RATE OF PRESSURE RISE: Greater than 138000 kPa/sec (greater than 20000 psi/sec or 1380 bar/sec) (aluminum, atomized and flake); 133100 kPa/sec (1331 bar/sec) (aluminum, 6 µm); 62100 kPa/sec (621 bar/sec) (aluminum, 17 µm); 13500 kPa/sec (135 bar/sec) (aluminum, 100 µm)

The dry powder is stable. Damp bulk dust may heat spontaneously and form flammable hydrogen gas.

Generation of dust, moisture, heat, sparks, flames or other sources of ignition.

Aluminum powder is odourless.

NONE - odourless and essentially non-irritating

This material is a REACTIVE FLAMMABLE solid and a DUST EXPLOSION HAZARD. Before handling, it is extremely important that engineering controls are operating and that protective equipment requirements and personal hygiene measures are being followed. People working with this chemical should be properly trained regarding its hazards and its safe use.

Absolutely no contact with incompatible materials such as water, strong acids, strong bases and oxidizing agents. Eliminate ignition sources. Keep away from heat. Do not use uncoated aluminum powder in areas equipped with sprinkler systems. Keep away from water. Post "DO NOT USE WATER" signs in area of use. Avoid using screw-cap bottles with cardboard liners which may accumulate moisture. Avoid generating dusts. Prevent the release of dusts into the workplace air. Wherever dust clouds may be generated, eliminate any possible contact with water, sparks, flames and other ignition sources. Post "NO SMOKING" signs. Good housekeeping is very important to prevent accumulations of dust. Prevent any build-up of dusts on ledges or other surfaces. The use of compressed air to clean equipment, clothing, etc. is not recommended. Dry sweeping is not recommended. Use an explosion-proof vacuum equipped with high efficiency filter(s).

Always inspect containers for damage or leaks before handling them. Do not transfer in storage area unless it is segregated by fire-resistant construction. Cautiously, transfer into sturdy containers made of compatible materials. Prevent damage to containers. Use dust-tight, labelled containers. Keep containers closed when not in use. Use only dry, clean utensils when handling. Never return contaminated material to its original container. Empty containers may contain residues which are hazardous. Do not perform any welding, cutting, soldering, drilling or other hot work on an empty container or transfer equipment until all flammable solids have been removed.

Follow handling precautions on Material Safety Data Sheet. Have suitable emergency equipment for fires, spills and leaks readily available. Practice good housekeeping. Maintain handling equipment. Comply with applicable regulations.

Engineering control methods to reduce hazardous exposures are preferred. Methods include mechanical ventilation (dilution and local exhaust), process or personnel enclosure, control of process conditions, and process modification (e.g., substitution of a less hazardous material). Administrative controls and personal protective equipment may also be required.

Use a non-sparking, grounded ventilation system separate from other exhaust ventilation systems. Exhaust directly to the outside. Locate dust collectors outside or in an isolated area. Provide dust collectors with explosion vents. Supply sufficient replacement air to make up for air removed by exhaust system.