Safely Working With Epoxies

Epoxy resins are generally known for high mechanical performance, low volatility, and predictable workability. When used properly, they can also be one of the safest options to use for both the hobbyist and professional worker in the composites, adhesives, and coatings industries.Entropy Resins’ formulations feature carefully selected ingredients with both user safety and environmental impact in mind. Although our resins are bio-based, they are not totally free of the required epoxide chemistry necessary to achieve the high-level of performance we strive for in our products. Therefore we suggest reading this guide prior using our epoxy systems. We advise reading the Material Safety Data Sheets that accompany our products and read all product labels and warnings. When in doubt, ask.Since epoxy resins are reactive, they also pose a chronic health risk due to overexposure by skin, inhalation, or ingestion. Your body’s reaction to overexposure is called sensitization. This means that even small doses of repeated direct contact with skin can eventually make someone allergic to the resin itself, causing anything from a small skin rash to a more systemic allergic response requiring medical attention. Susceptibility to epoxy sensitization varies amongst individuals. Therefore the best way to prevent sensitization problems is to limit exposure.


The risk of exposure to epoxy, hardener and mixed resin is highest when in liquid form. As epoxy resin cures, the components undergo chemical polymerization to form a non-hazardous solid. Once fully cured, epoxy and its components are less likely to enter the body.


Skin contact is the most common means of exposure to resins and hardeners. Even repetitive minor skin contact can cause chronic sensitization symptoms. In rare cases, with prolonged or repeated contact, the skin can absorb harmful reactive ingredients. Avoid contact with resin, hardeners, mixed epoxy, and, the often underestimated, partially cured sanding dust from epoxy. Wear protective gloves and clothing whenever you handle epoxies. Barrier skin creams provide supplementary protection. If you do get resin, hardener or mixed epoxy on your skin, remove it as soon as possible. Use oil-based or citrus skin cleaners to remove resin or mixed epoxy from your skin followed by soap and warm water. Always wash thoroughly with soap and warm water after using epoxy, removing amine blush or sanding epoxy from your skin. If you spill epoxy on your clothes, change them immediately. Use skin cleanser to remove any epoxy from you and your clothes. If you cannot completely remove it from your clothes, do not continue to wear them. If it is mixed epoxy, you may wear the clothes again once the epoxy has completely cured. Never use solvents to remove epoxy from your skin.

Stop using the product if you develop a reaction. Resume work only after the symptoms disappear, usually after several days. When you resume work, improve your safety precautions to prevent exposure to epoxy, its vapors and sanding dust. If problems persist, discontinue use and consult a physician.

Protect your eyes from contact with resin, hardeners, mixed epoxy, and sanding dust by wearing appropriate eye protection. If epoxy gets in your eyes, immediately flush them with water under low pressure for 15 minutes. If discomfort persists, seek medical attention.

Keep your workshop clean to avoid incidental contact. Avoid touching door handles, light switches and containers when you have epoxy residue on your gloves, as this is a common source of sensitization.


Exposure by inhaling vapors is unlikely, because epoxy products evaporate slowly. All of our epoxies have a low volatile organic content (VOC), but vapors can build up in unventilated spaces. Inhalation risks increase when ventilation is inadequate or when the products are heated. Avoid breathing concentrated vapors and especially sanding dust. When you can’t adequately ventilate your workspace, wear an approved respirator with an organic vapor cartridge.


Respirators are required when sanding epoxy, especially partially cured epoxy. Sanding partially cured epoxy produces airborne dust, which increases your risk of exposure by skin contact, inhaling or ingesting. Breathing partially cured epoxy dust is a common source of sensitization. Although epoxy cures quickly to a sandable solid, it may take over two weeks at room temperature, or elevated-temperature post-curing, to cure completely. Although epoxy is firm enough to sand within two hours, it may not cure completely for up to two weeks. Until then, the dust can contain unreacted hazardous components. Do not overlook or underestimate this hazard.


People rarely ingest epoxy, but it can happen when resin, hardener or mixed epoxy contaminates food, beverages or eating surfaces. Avoid ingesting epoxy by separating work areas from dining and break areas. Wash thoroughly after handling epoxy, especially before eating or smoking. If you swallow epoxy, drink large quantities of water, DO NOT induce vomiting. Hardeners are corrosive and can cause additional harm if vomited. Call a physician immediately. Refer to First Aid procedures on the Material Safety Data Sheet.


Aside from using respirators, goggles and protective clothing, consider the following steps to further protect yourself from epoxy or other hazardous products.

1) Make informed decisions about the products you use. Read all Safety Data Sheets and be well versed in safety precautions and measures. Reduce or eliminate the hazard source by using the least hazardous product to do the job.

2) Create a safe work environment. Install equipment or use procedures that prevent or reduce exposure; including ventilation and storage for hazardous materials. Choose a sufficient ventilation system for your needs, ranging from air-filtration and exhaust systems to basic floor or window fans. A dedicated storage cabinet or isolated area for hazardous materials can help reduce exposure. Regular cleaning of surfaces, will help reduce contamination by uncured materials.

3) Use the appropriate protective equipment (safety glasses, gloves, respirators, protective clothing, etc.) when using epoxy resins. At a minimum, use gloves, eye protection and protective clothing. Protect yourself from vapors by using a respirator with an organic vapor cartridge. Respiratory protection against epoxy dust, wood dust and nuisance dusts is a dust/mist mask or respirator. Read all accompanying instructions for proper use of safety equipment.


Clean up spills with a scraper, collecting as much material as possible. Follow up with absorbent towels. Use sand, clay or other inert absorbent material to contain large spills. DO NOT use sawdust or other fine cellulose materials to absorb hardeners. Clean resin or mixed epoxy residue with acetone, lacquer thinner, or alcohol. Follow all safety warnings on solvent containers. Clean hardener residue with warm soapy water. You may reclaim uncontaminated resin or hardener for use. DO NOT dispose of hardener in trash containing sawdust or other fine cellulose materials, they can spontaneously combust.

Safely dispose of resin, hardener and empty containers. Puncture a corner of the can and drain residue into the appropriate new container of resin or hardener. Do not dispose of resin or hardener as liquids. Mix and cure waste resin and hardener (in small quantities) to make a non-hazardous inert solid. CAUTION! Pots of curing epoxy can get hot enough to ignite surrounding combustible materials and give off hazardous fumes. Place pots of mixed epoxy in a safe and ventilated area, away from workers and combustible materials. Dispose of the solid mass only after it has completely cured and cooled. Follow federal, state or local disposal regulations.

Epoxy Resin and Hardeners are not considered hazardous wastes in their purchased form, using the criteria outlined in the Resource Conservation and Recovery Act (RCRA). Some state and local regulations, and disposal facilities may require additional lab analysis or evaluation of a Material Safety Data Sheet (MSDS) to determine if your wastes satisfy their requirements. It is always the end user’s responsibility properly dispose of wastes.

The following guidelines should help you make the right decisions when it comes time to dispose of unused epoxy resin and hardener.
– You do not have to designate unused resin and hardener as *waste* if you may use it on a future project. Entropy Resins’ epoxy products have a long shelf-life when stored in sealed containers. Simply use the product on another project.
– You may dispose of cured epoxy (resin and hardener mixed at the proper ratio and completely solidified) as a non-hazardous solid.
– Dispose of empty product containers only after you follow these simple *empty* rules: (1) You’ve made every effort to empty the container, and (2) no more than three percent by weight of the total capacity of the container remains in the container. Containers drain more completely when warm.
– Keep waste to a minimum. Work with small batches of epoxy. When emptying a container for disposal, collect the residue for use on a future project.
– Reclaim for further use epoxy resin or hardener collected from a spill or leak. If it is contaminated, designate it as waste. If you have used a solvent to clean up a spill, then the resultant mixture of solvent and epoxy may become a regulated hazardous waste.Respect the environment. Don’t release hazardous wastes directly to the land, air or water. Many communities organize periodic waste collections where consumers can take household wastes for safe disposal, usually free of charge.

The disposal guidelines above may not comply with the laws and regulations in your area. If you are uncertain, refer to local, state and federal regulations. Also, this section has addressed only the disposal of our epoxy resin and hardener. Boat building and repair projects generate many hazardous wastes, including bottom paint, gel coat, paints and solvents. Uncured, these materials can harm the environment, so identify and dispose of them properly.