Lye Safety Tips

February 24, 2020 12.45pm

In order to make soap, lye safety must be addressed. Oils must emulsify with lye, which begins the saponification process in soap making. During this process, it’s very important to make safety a top priority. Sodium hydroxide lye is an inorganic compound commonly found in drain cleaners like Draino. Sodium hydroxide lye is highly caustic and has the potential to burn the skin, but with the correct amount of care (and knowledge), sodium hydroxide is safe when handled properly. But because lye has the potential to be extremely dangerous,  it’s important to take every safety precaution when making using lye to make soap.

Sodium hydroxide lye is available in various forms, such as flakes, pellets, and powder. To make cold process soap, lye is introduced to a liquid such as distilled water. The liquid dissolves the lye and creates a lye solution. Mixing water and lye creates an exothermic reaction that causes a dramatic temperature increase. Adding lye to room temperature water can cause the water to reach temperatures up to 200 ° F. The mixture also creates fumes, which should not be inhaled. Below are basic lye safety tips that, if you follow closely, will make this process safe and secure.

Wear Proper Safety Gear:  When working with lye, wearing protective safety gear is a must. This includes eye goggles, gloves, long sleeves, and long pants. Covering your skin helps protect it from spills or drops of lye solution. Wearing surgical masks also help to avoid breathing in any fumes.

Mix Lye in an Appropriate Place: To ensure lye safety, the area in which you mix your lye solution should have good ventilation to avoid breathing in lye fumes. When the weather allows, mixing the lye solution outside will give you the best ventilation possible. When indoors, open a few windows or turn on a fan. In addition to ventilation, it’s important to make sure kids, pets and other distractions and tripping hazards are out of the house or don’t have access to your soaping space. 

Always Add Lye to Water (Never Water to Lye!): This is one of the most important tips for lye safety. When mixing water and lye the first step is to measure the correct amounts into separate containers. Once you have the correct amounts for your recipe, the lye should be slowly added to the water. NEVER add water to your lye! Doing so can cause the lye to expand, or erupt, out of the container.

Use an Appropriate Mixing Container:  It’s important to mix your lye solution in a durable and safe container. The container should be a sturdy, heat-resistant plastic or glass. Avoid a metal container as the lye solution gets incredibly hot. Also because lye and some metals produce a hazardous reaction. Sodium hydroxide and aluminum produce hydrogen gases, which can be extremely dangerous. Lye also reacts with tin. To be on the safe side, avoid metal containers entirely. If using glass, make sure your container is extremely sturdy (like Pyrex). You will want a container that is large enough to catch any splashes as you stir. Also, to be safe, mix your lye and water over a sink in case there are any spills.

Store Lye Appropriately: While waiting for the lye solution to cool to suitable soaping temperatures, make sure your container is clearly labeled “LYE” to ensure nobody touches or tampers with the solution. It’s also helpful to move it to a place where kids or pets will not touch or drink the solution. The jar of lye flakes, pellets or powder should always be kept out of reach of children, and should be properly labeled “POISON,” or “DO NOT TOUCH,” to ensure people do not tamper with the lye.

If You Get Lye on Your Skin: Accordingly the sodium hydroxide MSDS (Material Safety Data Sheet), if your skin meets lye, remove any contaminated clothing. Flush immediately with plenty of water for at least 15 minutes. Seek medical attention. If it meets eyes, flush immediately with water for at least 15 minutes and get medical attention. If inhaled, move to fresh air.

Although vinegar should not be used to treat lye burns on the skin, it can be used as a precaution during the cleanup process. A quick wipe of your workspace with a vinegar-soaked rag will neutralize any lye dust that may have gotten on the surface.