Solid Expressions™ Concrete Instructions and MSDS
General Instructions
MIXING
- Concrete should be mixed in a clean, clear plastic container free of grease or oils(I use clear plastic cups so I can see the bottom of the mixture to assure it is mixing thoroughly).
- Begin by adding a small amount of liquid to the powdered concrete. Add the liquid a bit at a time and incorporate thoroughly before adding more. The initial mixture will form pea-sized lumps but with the addition of a very small amount of liquid will turn to the consistency of thick yogurt. When you draw a palette knife across the top the concrete should have a wet smooth look.
- Depending on the type of concrete used, you will have between 5 and 15 minutes of work time. If the mixture begins to harden, it means the catalytic reaction has begun. Do not add more liquid to prolong the pot-life as it will only serve to lessen the strength of the final product.
- Pigments may be added at various times in the process, however;
- Dry pigments are mixed with the dry concrete before any liquid is added.
- Liquid pigments are added with the mixing liquid.
USES
- Filling a form - Any existing form can be filled with the wet concrete, tamped, and allowed to cure. Heating per above is possible; however, it will always take a bit longer to dry as the moisture can only evaporate out the top surface. After the form is filled, any inclusion may be placed in the wet concrete and allowed to remain "cemented" in place. After the hardening begins texture can be carefully introduced on the concrete surface by scratching, brushing, burnishing, etc.
- Casting - A simple mold may be formed using raw polymer clay, plaster, silicone, ceramic clay, sand, texture plates, alginates, etc. Concrete may also be cast into existing rigid forms as long as there are no undercuts and a release agent is used (don't use Vaseline or oil as they stain the concrete and hinder the curing process). Trowel the wet concrete into the mold and tamp from below to help air migrate up and out from the top. Allow 2 days for the curing time before unmolding the concrete. Alternatively, after a day the mold can be heated very slowly (concrete still in it) at a low temperature (150°-175° F) in a toaster oven or on a radiator. When removed from the mold there will still be moisture left in the concrete and again may be placed it a heated environment at a low temperature to hasten evaporation.
- Covering an armature - Concrete may be applied to a myriad of armatures including wood, plastic, screen, cloth, pierced metal, panty hose and many more. The concrete should be applied in thin coats as evenly as possible. Subsequent coats may be applied to build up a surface however, the under layer should be moistened with liquid (water or additive) before application of new concrete.
- Tablets - A tablet or billet can be formed by placing portions of the mixed concrete on a piece of waxed paper or the sticky side of masking tape. The specific shape of the final piece can be drawn on the paper or tape and the concrete mixture "corralled" to fit inside the drawing thus eliminating much of the final shaping after the piece has dried. If tape is used, inclusions may be stuck down (upside down) and the shape drawn around them so that when peeled up the concrete will have the inclusions precisely where you want them. The inclusions will be flush with the surface of the concrete tablet and be free of any concrete. Voids and spaces may be formed by placing any soft material on the tape and making sure it extends higher then the depth of the concrete tablet and retracting it after the curing has occurred.
FINISHING
- Shaping - Concrete formed in any of the above ways may be filed, sanded, ground, buffed and polished.
- Painting & Staining - Concrete can be painted with most paints and can also be tinted by sprinkling with pigments (try iron filings or instant coffee).
- Varnishes - Varnishes, waxes, some finishing oils, and their variations work well but the concrete must be completely dry before application.
- Cutting - Mizzy wheels, separating wheels, and diamond burrs work well on the flex shaft and finished pieces may be cut (carefully) on a lapidary saw or sanded on a belt sander.
Solid Expressions™ Concrete MSDS
The information provided in this Material Safety Data Sheet has been obtained from source(s) believed to be reliable. Crackerdog Design provides no warranties, express or implied and assumes no responsibility for the accuracy or completeness of the information contained herein
Section 1: Material or Component
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Section 2 - Hazardous Ingredients / Identity Information
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Component |
CAS# |
OSHA PEL (8-hour TWA) |
ACGIH TLV-TWA (2002) |
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Portland cement |
65997-15-1 |
15 mg/m3 (total dust); 5 mg/m3 (respirable dust) |
10 mg/m3 (total dust) |
| Crystalline Silica (Quartz) * | 14808-60-7 |
30 mg/m3 (total dust) /(percent silica + 2) 10 mg/m3 (respirable dust) /(percent silica + 2) |
0.1 mg/m3 (respirable dust) |
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Calcium sulfate, Gypsum |
7778-18-9 |
15 mg/m3 (Vacated) |
TWA: 10 mg/m3 (total duct) |
- Boiling Point: N/A
- Specific Gravity (H2O = 1) N/A
- Vapor Pressure (mm Hg.) None
- Appearance and Odor: Grey Powder, no odor
* The exposure limits are time-weighted average concentrations for an eight-hour workday and a forty-hour workweek. Crystalline silica exists in several forms; the most common which is quartz. If crystalline silica (quartz) is heated to more than 870° C, it can change to a form of Crystalline Silica known as Trydimite, and if crystalline silica is heated to more than 1470° C, it can change to a form of crystalline silica known as Cristobalite. The OSHA PEL for crystalline silica as Trydimite and Cristobalite is one half of the OSHA PEL for crystalline silica (quartz). The current OSHA permissible limit (PEL) for respirable dust containing crystalline silica (quartz) for the construction industry is measured in million of particles per cubic foot (mppcf) and is calculated using the formula in 29CFR* 21926.55 Continued inhalation of dust over a period of years without proper respirator and ventilation controls will cause silicosis and lung cancer. Current OSHA standard for crystalline silica (respirable dust) is 10mg silica per cubic meter of air divided by the percent Si02 averaged over an eight-hour work shift and for total dust is 30mg/m3 divided by the percent Si02 averaged over an eight-hour work shift
Section 3 - Fire and Explosion Hazard Data
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(Although these materials poses no fire-related hazards, a self-contained breathing apparatus is recommended to limit exposure to combustion products when fighting any fire.)
Section 4 – Health Hazard Data
Emergency Overview
These materials pose little immediate hazard. A single short-term exposure to these dry powders is not likely to cause serious harm. However, exposure to these wet materials can cause serious, potentially irreversible tissue (skin or eye) destruction in the form of chemical (caustic) burns or an allergic reaction. The same type of tissue destruction can occur if wet or moist areas of the body are exposed for sufficient duration to dry portland cement.
Potential Health Effects
- Relevant Routes of Exposure: Eye contact, skin contact, inhalation, and ingestion
- Effects resulting from eye contact: Exposure to airborne dust may cause immediate or delayed irritation or inflammation. Eye contact with larger amounts of dry powder or splashes of wet Portland cement may cause effects ranging from moderate eye irritation to chemical burns and blindness. Such exposures require immediate first aid (see section IV) and medical attention to prevent significant damage to the eye.
- Effects resulting from skin contact: Discomfort or pain cannot be relied upon to alert a person to a hazardous skin exposure. Consequently, the only effective means of avoiding skin injury or illness involves minimizing skin contact, particularly contact with wet cement. Exposed persons may not feel discomfort until hours after the exposure has ended and significant injury has occurred. Exposure to dry portland cement may cause drying of the skin with consequent mild irritation or more significant effects attributable to aggravation of other conditions. Dry portland cement contacting wet skin or exposure to moist or wet portland cement may cause more severe skin effects including thickening, cracking or fissuring of the skin. Prolonged exposure can cause severe skin damage in the form of (caustic) chemical burns. Page 2 of 4 Some individuals may exhibit an allergic response (e.g., allergic contact dermatitis) upon exposure to portland cement, possibly due to trace amounts of chromium. The response may appear in a variety of forms ranging from a mild rash to severe skin ulcers. Persons already sensitized may react to the first contact with the product. Other persons may experience this effect after years of contact with portland cement products.
- Effects resulting from inhalation: These materials contains small amounts of free crystalline silica. Prolonged exposure to respirable free crystalline silica can aggravate other lung conditions and cause silicosis, a disabling and potentially fatal lung disease and/or other diseases. Risk of injury or disease depends on duration and degree of exposure. (Also see “Carcinogenic potential” below.) Exposure to these materials may cause irritation to the moist mucous membranes of the nose, throat, and upper respiratory system. It may also leave unpleasant deposits in the nose.
- Effects resulting from ingestion: Although small quantities of dust are not known to be harmful, ill effects are possible if larger quantities are consumed. These materials should not be eaten.
- Carcinogenic potential: The exposure limits are time-weighted average concentrations for an eight-hour workday and a forty-hour workweek. Crystalline silica exists in several forms; the most common which is quartz. If crystalline silica (quartz) is heated to more than 870° C, it can change to a form of Crystalline Silica known as Trydimite, and if Crystalline Silica is heated to more than 1470° C, it can change to a form of crystalline silica known as Cristobalite. The OSHA PEL for crystalline silica as Trydimite and Cristobalite is one half of the OSHA PEL for crystalline silica (quartz). The current OSHA permissible limit (PEL) for respirable dust containing crystalline silica (quartz) for the construction industry is measured in million of particles per cubic foot (mppcf) and is calculated using the formula in 29CFR* 21926.55 Continued inhalation of dust over a period of years without proper respirator and ventilation controls will cause silicosis and lung cancer. Current OSHA standard for crystalline silica (respirable dust) is 10mg silica per cubic meter of air divided by the percent Si02 averaged over an eight-hour work shift and for total dust is 30mg/m3 divided by the percent Si02 averaged over an eight-hour work shift.
- Medical conditions which may be aggravated by inhalation or dermal exposure:
- Pre-existing upper respiratory and lung diseases
- Unusual (hyper) sensitivity to hexavalent chromium (chromium+6) salts.
Section 5 – Emergency and First Aid Procedures
- Eyes: Immediately flush eyes thoroughly with water. Continue flushing eye for at least 15 minutes, including under lids, to remove all particles. Call physician immediately.
- Skin: Wash skin with cool water and pH-neutral soap or a mild detergent. Seek medical treatment in all cases of prolonged exposure to wet cement, wet cement mixtures, wet concrete liquids from fresh cement products, or prolonged wet skin exposure to dry cement. Inhalation of
- Airborne Dust: Remove to fresh air. Seek medical help if coughing or other symptoms do not subside. (Inhalation of gross amounts of portland cement requires immediate medical attention.)
- Ingestion: Do not induce vomiting. If conscious, have the victim drink plenty of water and call a physician immediately.
Section 6 – Reactivity Data
- Conditions Known to Cause Instability: Product is stable
- Hazardous Decomposition: N/A
- Incompatibility/Materials to avoid: Product is incompatible with organic and inorganic acids. Acid will react with cement and carbonates.
Section 7 – Special Protection Information
- Skin Protection: Prevention is essential to avoiding potentially severe skin injury. Avoid contact with unhardened wet portland cement products. If contact occurs, promptly wash affected area with soap and water. Where prolonged exposure to unhardened portland cement products might occur, wear impervious clothing and gloves to prevent skin contact. Where required, wear sturdy boots that are impervious to water to eliminate foot and ankle exposure. Do not rely on barrier creams; barrier creams should not be used in place of impervious gloves and clothing. Periodically wash areas contacted by dry portland cement or wet cement or concrete with a pH neutral soap. Wash again at the end of the work. If irritation occurs, immediately wash the affected area and seek treatment. If clothing becomes saturated with wet concrete, it should be removed and replaced with clean, dry clothing.
- Respiratory protection: Avoid actions that cause dust to become airborne. Use local or general ventilation to control exposures below applicable exposure limits. Use NIOSH/MSHA-approved (under 30 CFR 11) or NIOSH-approved (under 42 CFR 84) respirators in poorly ventilated areas, if an applicable exposure limit is exceeded, or when dust causes discomfort or irritation. (Advisory: Respirators and filters purchased after July 10, 1998, must be certified under 42 CFR 84.) Ventilation: Use local exhaust or general dilution ventilation to control exposure within applicable limits.
- Eye Protection: In conditions where user may be exposed to splashes or puffs of these materials, wear safety glasses with side shields or goggles. In extremely dusty or unpredictable environments, wear unvented or indirectly vented goggles to avoid eye irritation or injury. Contact lenses should not be worn when working with portland cement or fresh cement products.
Section 8 – Spill, Leak and Disposal
- Storage Requirements: Store in a dry, cool area. Keep these materials dry until used. Normal temperatures and pressures do not affect the material.
- Spill and Leak Disposal: Avoid inhalation of dust and contact with skin. Collect dry material using a scoop. Vacuum any spills with a HEPA type vacuum cleaner. Avoid creating dusts. Do not wash down any drains or sewer lines as it may solidify and harden in the drain.
- Waste Disposal: Avoid actions that cause dust to become airborne. Wear appropriate personal protective equipment as described in Section 7. Scrape up wet material and place in an appropriate container. Allow the material to “dry” before disposal. Do not attempt to wash these materials down drains. Dispose of waste material according to local, state, and federal regulations.
Crackerdog Design
Solid Expressions™ Concrete Disclaimer
As always, when working with any material, we need some basic facts and to use common sense. So, there are a few guidelines we recommend you follow when working with concrete. It is advisable to use a simple nuisance mask when working with your concrete. If these masks are a nuisance to you by fogging up your glasses (like me) you can simply tie a bandana around your nose and mouth.
Of course, don’t breath in excess amounts of the dust, wash your hands thoroughly after handling and mixing, use disposable mixing cups and sticks. Let the excess dry in the disposable container, and do NOT rinse it down the drain! By all means discourage yourself from sprinkling it on your oatmeal in the morning. We all want a breakfast that sticks with us, but a bit of protein is more effective than concrete!