How to Work Safely with - Hazardous Products using the "Skull and Crossbones" Pictogram

The symbol within the pictogram is a human skull with two crossed bones behind it. The symbol indicates that hazardous products with this pictogram can cause death or poisoning.

Hazardous products with this pictogram can be safely worked with if proper storage and handling practices are followed.

Only one WHMIS hazard class uses the skull and crossbones pictogram – acute toxicity. This hazard class is different than other hazard classes because it individually considers each applicable route of exposure - oral (swallowed or ingested), dermal (skin contact) and inhalation (breathing).

There are 4 categories in the acute toxicity hazard class, but the skull and crossbones pictogram is only assigned to 3 categories for each route of exposure:

• Acute toxicity (Oral) – Categories 1, 2, and 3
• Acute toxicity (Dermal) – Categories 1, 2, and 3
• Acute toxicity (Inhalation) – Categories 1, 2, and 3

The exclamation mark pictogram is assigned to Category 4 for each route of exposure.

Acute toxicity refers to effects occurring:

• following skin contact or ingestion of a single dose of a substance, or multiple doses given within 24 hours, or
• an inhalation exposure of 4 hours.

Acute toxicity can result from exposure to the product itself, or to a product that, upon contact with water, releases a gaseous substance that is able to cause acute toxicity.

The WHMIS signal words and hazard statements for the hazard classes and categories assigned the skull and crossbones pictogram are:

A supplementary hazard statement is required if the product, upon contact with water, releases a gas that can cause acute toxicity. In this situation, the required statement for a gas that is:

• Acute toxicity (Inhalation) – Category 1 or 2 is “In contact with water, releases gases which are fatal if inhaled.”
• Acute toxicity (Inhalation) – Category 3 is “In contact with water, releases gases which are toxic if inhaled.”

In addition to the specific hazards identified by the skull and crossbones pictogram, it is important to remember that the product may have other hazards, for example:

• other health hazards such as skin corrosion or irritation, carcinogenicity, and/or specific target organ toxicity (single or repeated).
• physical hazards such as corrosive to metals, flammability or reactivity.

• Always check the SDS for information about ALL of the hazards and the necessary precautions for the product being used. Ask questions if you are not sure.
• If it is not possible to eliminate the use of an acute toxicity product, evaluate whether it is possible to use a substitute, such as a less hazardous product (e.g., products that are classified for acute toxicity - category 3 or 4 are less hazardous than those classified for acute toxicity - category 1 or 2).
• Follow the safe work practices specified on the SDS and by your employer.
• Always work with the smallest amount possible.
• Inspect containers for damage or leaks before handling. Open containers slowly and carefully to prevent spills and dispersal into the air.
• Keep containers tightly closed when not in use.
• Avoid generating or releasing vapour, mist, dust or gas into the workplace air. Prevent any uncontrolled release of the product.
• Avoid dry sweeping of solid product. Use a pre-wetting technique or vacuum equipped with high efficiency (HEPA) filter(s) instead.
• For inhalation hazards, do not breathe dust, fume, mist, vapours or spray. Use only outdoors or in a well-ventilated area. In case of inadequate ventilation, wear respiratory protection.
• For oral and dermal hazards, wash hands thoroughly after handling. Do not eat, drink, or smoke when using these products.
• For dermal hazards, do not get in eyes, on skin, or on clothing. Wear protective gloves, protective clothing, if required.
• Personal protective equipment (PPE) may include respiratory protection, eye and face protection, and chemical protective clothing such as gloves and an apron made from materials that protect against the acute toxicity product.
• Know the typical symptoms of exposure and appropriate first aid procedures. Immediately report any signs of illness to your supervisor.
• Sometimes a worker should not work alone with an acute toxicity product.
• Remove contaminated clothing and protective equipment before entering eating areas or leaving the work area.
• Practice good housekeeping (e.g., keep surfaces clean, do not allow dust to accumulate).
• Immediately report spills, leaks or problems with hazard control measures.
• Inform maintenance personnel about the hazards of products to which they might be exposed.

• Be aware of any other special storage conditions. Read the SDS for information.
• For inhalation hazards, store in a well-ventilated place. Keep the container tightly closed.
• Store in a cool, dry area, away from direct sunlight and exit paths. Post warning signs.
• Store locked up, if required.
• Avoid storing large quantities if possible. Do not stockpile.
• Inspect containers and storage area regularly for signs of leaks or damage. Contain spills or leaks by storing product containers in trays made from compatible materials.
• Empty containers may contain hazardous residue. Store separately. Keep closed.
• Store containers at a convenient height for handling, below eye level if possible. High shelving increases the risk of dropping containers and the severity of container damage, personal injury or exposure if a fall occurs.
• Ensure that appropriate fire-fighting and spill clean-up equipment is readily available.
• Follow all applicable health and safety regulations, and fire and building codes.

Understand and practice emergency procedures so that you know what to do if it becomes necessary.

• Ensure that an eyewash and emergency shower are readily available in the immediate work area. These devices must be tested regularly.
• In the event of a spill or leak, immediately put on an escape-type respirator, if required, and exit the area.
• Immediately report ventilation failures, leaks or spills to your supervisor.
• Have spill control procedures and equipment ready (e.g., absorbent spill control materials, PPE etc.).
• Immediately report leaks to your supervisor, warn people in the area, and move to a safe location, if necessary.
• Ensure that appropriate medical response is available (e.g., antidotes, copy of SDS for the emergency doctor, first responders, etc.)
• IF SWALLOWED: Immediately call a Poison Centre or doctor. Specific treatment may be required. Rinse mouth.
• IF ON SKIN: Wash with plenty of water. Immediately call a Poison Centre or doctor for more severe hazards or if you feel unwell. Specific treatment may be required. Take off immediately all contaminated clothing and wash it before reuse.
• IF INHALED: Remove the person to fresh air and keep comfortable for breathing. Immediately call a Poison Centre or doctor. Specific treatment is urgent.