OSH Answers Fact Sheets
Easy-to-read, question-and-answer fact sheets covering a wide range of workplace health and safety topics, from hazards to diseases to ergonomics to workplace promotion. MORE ABOUT >
What are other names or identifying information for silica?
Other Names: Crystaline silica, Quartz; Silicone dioxide; Quartz
Main Uses: Many uses including in mining, fabrication, manufacturing, and construction
Appearance: Colourless crystals.
Canadian TDG: Not specifically listed in Canadian TDG Regulations, but may be regulated as part of a chemical family or group Not Otherwise Specified (N.O.S.). Consult the regulations.
What is the WHMIS 1988 classification?
D2A - Very Toxic (Carcinogenicity)
What are the most important things to know about silica in an emergency?
Emergency Overview: Colourless crystals. Odourless. Will not burn. VERY TOXIC. Prolonged or repeated exposure causes damage to lungs. CANCER HAZARD. May cause cancer, if inhaled.
What are the potential health effects of silica?
Main Routes of Exposure: Inhalation; skin contact; eye contact.
- Inhalation: At high concentrations: can irritate the nose and throat.
- Skin Contact: Not irritating.
- Eye Contact: May cause slight irritation as a "foreign object". Tearing, blinking and mild temporary pain may occur as particles are rinsed from the eye by tears.
- Ingestion: Not harmful.
- Effects of Long-Term (Chronic) Exposure: VERY TOXIC. Can cause lung damage if the dust is breathed in. Symptoms may include shortness of breath, chronic cough and weight loss. There may be a decrease in lung function and ability to do some physical activities. In severe cases, there can be effects on the heart and death from heart failure.
- Carcinogenicity: CARCINOGEN. Known to cause: lung cancer.
International Agency for Research on Cancer (IARC): Group 1 - Carcinogenic to humans.
American Conference for Governmental Industrial Hygienists (ACGIH): A2 - Suspected human carcinogen.
- Teratogenicity / Embryotoxicity: Not known to harm the unborn child.
- Reproductive Toxicity: Not known to be a reproductive hazard.
- Mutagenicity: Conclusions cannot be drawn from the limited studies available.
What are first aid measures for silica?
Inhalation: Take precautions to ensure your own safety before attempting rescue (e.g. wear appropriate protective equipment). Move victim to fresh air.
Skin Contact: Quickly and gently blot or brush away excess chemical. Wash gently and thoroughly with lukewarm, gently flowing water and non-abrasive soap for 5 minutes.
Eye Contact: Quickly and gently blot or brush chemical off the face. Immediately flush the contaminated eye(s) with lukewarm, gently flowing water for 5 minutes, while holding the eyelid(s) open. If irritation or pain persists, see a doctor.
Ingestion: Have victim rinse mouth with water. Call a Poison Centre or doctor if the victim feels unwell.
First Aid Comments: If exposed or concerned, see a doctor for medical advice. All first aid procedures should be periodically reviewed by a doctor familiar with the chemical and its conditions of use in the workplace.
Note to Physicians: Some jurisdictions specifically regulate an ingredient of this product and require a complete medical surveillance program. Specific information should be sought from the appropriate government agency in your jurisdiction.
What are fire hazards and extinguishing media for silica?
Flammable Properties: Does not burn.
Suitable Extinguishing Media: Not combustible. Use extinguishing agent suitable for surrounding fire.
Specific Hazards Arising from the Chemical: None known. Not known to generate any hazardous decomposition products in a fire.
What are the stability and reactivity hazards of silica?
- Chemical Stability: Normally stable.
- Conditions to Avoid: Generation of dust.
- Incompatible Materials: Increased risk of fire and explosion on contact with: oxidizing agents (e.g. peroxides). Not corrosive to metals.
- Hazardous Decomposition Products: None known.
- Possibility of Hazardous Reactions: None known.
What are accidental release measures for silica?
Personal Precautions: Evacuate the area immediately. Isolate the hazard area. Keep out unnecessary and unprotected personnel. Ventilate area.
Methods for Containment and Clean-up: Avoid dry sweeping. If necessary, use a dust suppressant such as water. Do not use compressed air for clean-up. Collect using shovel/scoop or approved HEPA vacuum and place in a suitable container for disposal.
What handling and storage practices should be used when working with silica?
Handling: Before handling, it is important that all engineering controls are operating and that protective equipment requirements and personal hygiene measures are being followed. Only trained personnel should work with this product. Immediately report leaks, spills or failures of the safety equipment (e.g. ventilation system). Avoid generating dusts. Prevent accidental contact with incompatible chemicals.
Storage: Keep amount in storage to a minimum. Empty containers may contain hazardous residue. Store separately. Keep closed. Store in an area that is: separate from incompatible materials.
What is the American Conference of Governmental Industrial Hygienists (ACGIH®) recommended exposure limit for silica?
ACGIH® TLV® - TWA: 0.025 mg/m3 A2 (respirable)
Exposure Guideline Comments: TLV® = Threshold Limit Value. TWA = Time-Weighted Average. A2 = Suspected human carcinogen.
What are the engineering controls for silica?
Engineering Controls: Use a local exhaust ventilation and enclosure, if necessary, to control amount in the air. It may be necessary to use stringent control measures such as process enclosure to prevent product release into the workplace.
What Personal Protective Equipment (PPE) is needed when working with silica?
Eye/Face Protection: Safety goggles suitable for dust protection.
Skin Protection: It is good practice to prevent skin contact.
Up to 0.5 mg/m3:
(APF = 10) Any particulate respirator equipped with an N95, R95, or P95 filter (including N95, R95, and P95 filtering facepieces) except quarter-mask respirators. The following filters may also be used: N99, R99, P99, N100, R100, P100.
APF = Assigned Protection Factor
Recommendations apply only to National Institute for Occupational Safety and Health (NIOSH) approved respirators. Refer to the NIOSH Pocket Guide to Chemical Hazards for more information.
Although every effort is made to ensure the accuracy, currency and completeness of the information, CCOHS does not guarantee, warrant, represent or undertake that the information provided is correct, accurate or current. CCOHS is not liable for any loss, claim, or demand arising directly or indirectly from any use or reliance upon the information.