TIME-WEIGHTED AVERAGE (TLV-TWA): 3.5 mg/m³ - Carcinogenicity Designation A4

TLV BASIS - CRITICAL EFFECT(S) : Lung

CARCINOGENICITY DESIGNATION A4 - Not Classifiable as a Human Carcinogen: Inadequate data on which to classify the substance as a human and/or animal carcinogen.

NOTE: This substance has been identified by other sources as a suspect or confirmed human carcinogen.

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.

In general, pure carbon black is difficult to ignite, does not undergo spontaneous combustion, and is not a dust explosion hazard. Red hot metal, electric sparks and burning magnesium ribbon will not cause carbon black dust to ignite explosively. However, carbon black can be ignited by an open flame, glowing metal, sparks or lighted cigarettes. Once ignited it burns slowly with the production of toxic carbon monoxide. Storage fires may go undetected for some time, unless stirred or sparks are present. If impurities are present on the carbon black (e.g. oil), then there is a risk of dust explosions. The risk of lamp black dust explosions is increased by the presence of unconsumed oil that adheres to the carbon. Dust explosions may occur if the oil content exceeds 13% (MINIMUM CLOUD IGNITION TEMPERATURE reported as 730 deg C). If air concentrations exceed 50 or 60 g/m³, carbon black may explode in the presence of a high energy ignition source, such as a gas explosion. Ignition of dust clouds has also been obtained by using 28 g of gunpowder (MINIMUM CLOUD IGNITION TEMPERATURE reported as 510 deg C). The MINIMUM LAYER IGNITION TEMPERATURE of acetylene carbon black is reported as 900 deg C. Higher volatile organic content increases fire risk. Carbon blacks containing over 8% volatiles may be an explosion hazard.

Normally stable and unreactive. Freshly produced carbon black may be prone to heating when initially exposed to air. Heat may also be generated in the presence of oxidizable oils.

Open flames, glowing metal, sparks, generation of dust

Carbon black is odourless.

Information not available for evaluation

This material is a VERY TOXIC (POSSIBLE CANCER HAZARD AND POSSIBLE MUTAGEN) solid. It may also be a DUST EXPLOSION HAZARD depending on the impurities present. Before handling, it is extremely important that engineering controls are operating and that protective equipment requirements and personal hygiene measures are being followed Only authorized personnel should have access to this material. They should be properly trained regarding its hazards and its safe use. Maintenance and emergency personnel should be advised of potential hazards.

If carbon black is released, immediately evacuate the area. Immediately report leaks, spills or ventilation failures. When there is large-scale use of this material, closed handling systems for processes involving this material should be considered.

Use in smallest possible amounts. Avoid generating dusts. Prevent the release of dust into workplace air.

Eliminate all ignition sources, (e.g. sparks, open flames). Post "NO SMOKING" signs. It is very important to keep areas where this material is used clear of other materials which can burn (e.g. cardboard, sawdust). If impurities are present on the carbon black which could put it at risk of being an explosion hazard, then use a non-sparking ventilation systems, approved explosion-proof equipment and intrinsically safe electrical systems in areas of use. Inspect containers for leaks before handling. Use the proper tools to open containers. Ripping open a container can cause an uneven tear, thus making spills more likely. Use dust-tight, labelled containers. Keep containers closed when not in use.

Do not use with incompatible materials such as strong oxidizing agents (e.g. chlorates and nitrates). There is an increased risk of fire and explosion. Good housekeeping is very important. Keeping work areas clean is essential. The use of compressed air to clean equipment, clothing, etc., is not recommended. Maintain good personal hygiene. If a closed handling system is not being used, showering at the end of each workshift may be necessary. Separate storage facilities for street clothes and for protective clothing and equipment may also be necessary.

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

Engineering methods to control hazardous conditions 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 local exhaust ventilation, and process enclosure if necessary, to control airborne dust. Locate dust collectors outside or where permitted by regulation. If impurities are present which could put this material at risk of being an explosion hazard, then use a non-sparking, grounded ventilation system, separate from other exhaust ventilation systems. In this case, approved explosion-proof equipment and intrinsically safe electrical systems should be provided in areas of large-scale use.

Supply sufficient replacement air to make up for air removed by exhaust system.