Beginner Soapmaking Series – Lye Safety and Handling

Lye is a hazardous substance that must be handled with care.  It can cause serious chemical burns and blindness.  Lye is safe for soapmaking provided you take safety precautions.
Beginner Soapmaking Series - Lye Safety and Handling
  • Always wear goggles or protective eyewear.  Lye, lye water, and fresh soap can cause serious eye injuries. Avoid injury by wearing goggles.  If you do get lye in your eyes, rinse with cold water immediately and seek medical attention.
  • Always wear protective clothing and gloves.  Wearing gloves, long sleeved shirts, long pants, and closed-toe shoes will protect you against splashes with the lye mixture or fresh soap. If you do get lye on your skin, rinse with cold water to get the soap off quickly and immediately pour vinegar on the affected area.
  • Always have vinegar ready for emergencies.  Vinegar should be kept out where you are working.  If it is near the sink, you will have it ready for any accidents.  Vinegar should be applied to the skin to neutralize lye.  If you spill lye on the work area, use vinegar to clean it up.  A splash of lye or fresh soap may not hurt immediately but can still leave permanent damage.
  • Always add lye to water.  Put your lye into the water, not the other way round, to prevent dangerous splashes or severe volcanic reactions.  When mixing with oils, add the lye water to the oils.  Lye is always the ingredient that does the pouring.
  • Always mix lye carefully.  When lye is added to water, it will rapidly heat up to about 200 degrees Fahrenheit.  Mix in a large heat-safe container.  It is a good practice to place the container in the sink while mixing the lye and water.
Some additional precautions are listed below:
  •  Soapmaking is not recommended for children because of the potential danger that lye poses.  Children and pets should not be permitted in your soaping area while you are working.
  • Carefully read the warning label on the lye bottle.  Lye is also known as caustic soda (sodium
  • Use only pure lye granules.  Do not make the mistake of substituting drain cleaner.  It contains other ingredients that you would not want in your soap.  Lye for soapmaking must be 100% sodium hydroxide.
  • Be sure to keep the lid tight on the bottle of lye to prevent spills.  Also, be aware that moisture in the air will weaken its strength and cause it to form lumps.
  • Lye can be fatal if swallowed. 
  • Beginner Soapmaking Series - Lye Safety and HandlingBe sure to work in a well-ventilated area.  Vapors released from the lye when it is first mixed with water are quite noxious, and can greatly irritate the lungs.  Never lean over the mixture when adding lye to water.
  • Lye can remove paint, so be careful not to let it come in contact with any painted surfaces.  If lye, lye water or even freshly made soap splatters on any painted surface, wash the area quickly with water and detergent.  Rinse with clear water and wipe dry.
  • Freshly made soap can burn and irritate the
    therefore it’s best not to handle soap with bare hands for at least 48 hours.
  • Do not use any containers made of tin, zinc or aluminum.  Lye will react adversely with them.
  • Recommended containers for mixing your soap include glass, plastic, stainless steel, enamel, and heat-proof stoneware.
In case of a lye emergency, follow this information taken from the MSDS* sheet for sodium hydroxide:
If Swallowed
Rinse mouth with water and drink one to two glasses of water. Do not induce vomiting! Immediately get medical attention or call your poison control center at 1-800-222-1222.
If in Eyes
Immediately flush eyes with water. Remove any contact lenses and continue to flush eyes with water for at least 20 minutes.  Immediately get medical attention or call your poison control center at 1-800-222-1222.
If on Skin
Gently wipe product from skin and remove contaminated clothing.  Flush skin with plenty of water for at least 15 minutes and then wash thoroughly with soap and water.  Contact a physician or call your poison control center at 1-800-222-1222.  [The MSDS is often kept for people in warehouses or packaging facilities that typically do not have vinegar, hence the fact that it was not mentioned on the form.]
*For more information on lye, see the
downloadable and printable MSDS data sheet at: