Trade Name: Granitepatch™
Producer’s Name: Granite Rock Company
Address: 350 Technology Dr
PO Box 50001
Watsonville, CA 95077-5001
Phone Number: 831.768.2000
Date Prepared: June 1999
Date Revised: January 2009
Prepared by: Paul C. Lessard, Ph.D.

  1. ACGIH TLV: American Conference of Industrial Hygienist Threshold Limit Value (TLV) time-weighted average (TWA)
  2. OSHA PEL: Occupational Safety and Health Administration Permissible Exposure Limit for an 8-hour time weighted average
  3. NIOSH REL: National Institute for Occupational Safety & Health, Recommended Exposure Limit
  4. Measured by NIOSH Method 7500, DCM Science Labs, Wheat Ridge, Colorado

Overview: Granitepatch™ is a proprietary mixture containing 93–97% aggregates and 4–7% asphalt binder. If cut or drilled, it may generate crystalline silica containing dust.

Potential Health Effects

  • Eye Contact: Direct contact with asphalt dust may cause irritation to eyes by abrasion.
  • Skin Contact: Direct contact with asphalt dust may also cause skin irritation.
  • Skin Absorption: Not expected to be a significant exposure route.
  • Ingestion: Small amounts (a tablespoonful) of hardened asphalt/asphalt dust swallowed during normal handling operations are not likely to cause injury. Ingestion of large amounts of hardened asphalt/asphalt dust may cause gastrointestinal irritation and blockage.
  • Inhalation: Asphalt dusts containing crystalline silica may irritate the nose, throat, and respiratory tract. Coughing, sneezing, chest pain, shortness of breath, inflammation of mucous membrane, and flu-like fever may occur following exposures in excess of appropriate exposure limits. Repeated excessive exposure may cause pneumoconiosis, such as silicosis and other respiratory effects including lung cancer.


  • Eye Contact: Immediately flush with plenty of water for at least 15 minutes. Do not attempt to remove asphalt particles from eyes. GET IMMEDIATE MEDICAL ATTENTION.
  • Skin Contact: Immediately FLUSH WITH COOL WATER for at least 15 minutes. Clean skin with waterless hand cleaner. Seek medical aid if irritation persists or develops.
  • Inhalation: Remove from exposure. Seek medical aid if respiratory difficulty persists or develops.
  • Swallowed: SEEK MEDICAL AID. Do not induce vomiting.


  • Flash Point: >450°F
  • Flash Point Method: COC
  • Extinguishing Media: Agents approved for Class B fires (e.g., CO2, dry chemical, or foam, water fog).
  • Special Fire Fighting Procedures: Use NIOSH/MSHA approved SCBA and full protective equipment.
  • Unusual Fire & Explosion Hazards: If hydrogen sulfide is present in sufficient quantities, flammable limits can increase to 4–45% by volume and pyrophoric iron compounds can be formed. In this case, use self-contained breathing apparatus (SCBA) in the pressure demand mode.

Spill Response Procedures: Remove all heat and ignition sources and increase ventilation. Use water vapor to reduce airborne vapors. For small spills, use sand or absorbent to capture. Place in sealed containers for disposal.
Preparing Waste for Disposal: Disposal must be in accordance with applicable federal, state, and local regulations. Enclosed-controlled incineration recommended, depending on jurisdiction.

Respiratory Protection: NIOSH/MSHA approved dust respirators with a N95 rating or bettershould be used where dust levels exceed or are likely to exceed exposure levels defined in Section 2. Respirator use must comply with applicable MSHA or OSHA standards which include a provision for fit testing, cleaning, training in correct usage and a fitness test for respirator use. See NIOSH Publication 2008-140 and for more information.

  • Eye Protection: Safety glasses with side shields should be worn at all times.
  • Gloves: Nitrobutyl rubber or neoprene.
  • Other Clothing: Long sleeves.
  • Work Practices: Do not smoke.
  • Hygiene Practices: Wash exposed skin with soap and water.


  • Other Handling Requirements: No special measures required.
  • Protective Measures During Maintenance of Contaminated Equipment: No special measures required.
  • Storage: Keep adequate ventilation in outside storage. Hydrogen sulfide gas may accumulate in storage tanks and bulk transport compartments containing asphalts.


  • Vapor Density (air=1): >5
  • Specific Gravity: 1.0–2.5
  • Melting Point: N/A
  • Boiling Point: Approx. 900°F
  • Solubility in Water: Negligible, <0.1%
  • Evaporation Rate: Negligible
  • Vapor Pressure: <0.1
  • Appearance and Odor: Black semi-solid mixture


  • Reactivity: Material is stable and will not polymerize. May react with strong oxidizing agents such as chlorates, nitrates and peroxides. At room temperature, hydrogen sulfide may be given off.
  • Materials & Conditions to Avoid: High temperature heating.
  • Hazardous Decomposition Products: Heating this material may produce hydrogen sulfide.

Granitepatch™ is a mixture of aggregates and liquid asphalt oil. The aggregates may contain crystalline silica which is a naturally occurring substance found in soil and rock formations. Should the mixture release dust (by cutting, for example), it is possible that the dust may contain a small content of crystalline silica. The IARC, NTP and OSHA do not list asphalt binder as a carcinogen. The oxidation of polycyclic aromatic hydrocarbons in the asphalt removes the carcinogenic potential.

Crystalline silica is a naturally occurring substance found in soil and rock formations. Crystalline silica is present in trace amounts in the atmosphere air as particulate. Crystalline silica is one of several crystalline polymorphs (including trydimite, cristobalite) of silicon dioxide. When heated to 870°C, crystalline silica transforms to trydimite, and when heated to 1,470°C it can transform to cristobalite. Chronic or ordinary silicosis is the most common form of silicosis which can occur after many years of exposure to relatively low levels of airborne respirable dust.

Crystalline silica is listed by the National Toxicology Program in a category which may reasonably be anticipated to be a carcinogen, and by the International Agency for Research on Cancer (IARC) as a Group 1 carcinogenic. After years of study, the non-governing IARC concluded in 1997 that there was “sufficient evidence in humans for the carcinogenicity of crystalline silica in the forms of quartz or cristobalite from occupation sources.” The IARC noted that carcinogenicity was not detected in all industries, and that toxicity may depend on “external factors affecting its biological activity or distribution of its polymorphs.”

The information contained in this MSDS is based on tests, experience and other information which Granite Rock Company believes reliable and is supplied for informational purposes only. Since conditions of use are outside of our control, Granite Rock Company disclaims any liability for damage or injury which results from use of the above information. Nothing contained herein shall constitute a guarantee, warranty (including warranty of merchantability) or representation (including freedom from patent liability) by Granite Rock Company with respect to the information, the material described, or its use for any specific purpose, even if that purpose is known to Granite Rock Company.

Pdf GranitePatch MSDS

Chemical Names CAS Number Quantity (Percent) Formula ACGIH TLV TWA OSHA PEL NIOSH REL
Petroleum distillate (asphalt) 8052-42-4 4-7 various 0.5 mg/m3 (as fumes)
Hydrogen sulfide 7783-06-4 <1 H2S 10 ppm 20 ppm
Crystalline silica (aggregate) 14808-60-7 13.5 SiO2 0.025 mg/m3 10 mg/m3 %SiO2+2