Mixing Chemicals Properly

by Lawton Brothers | Feb 08, 2018


Few people realize the amount of knowledge and effort that goes into cleaning and maintaining a commercial space. Keeping a school, an office, or even a construction trailer up to par frequently involves the use of harsh chemicals, advanced equipment, and a thorough knowledge of handling both. Mixing chemicals, for example, requires in-depth familiarity with what products can and can’t be mixed, how to measure and mix chemicals, and how to stay safe while doing so.

Chemicals That Should Never be Mixed

Most people know they should not mix certain chemicals such as ammonia and bleach. But, there are many combinations of common household items that must be avoided. Here is a list of everyday household items that should never be mixed:

  • Bleach and Vinegar – Mixing these two items will release toxic chlorine and chloramine vapors which can cause a nasty chemical burn, especially in the eyes and lungs.

  • Rubbing Alcohol and Bleach - Bleach contains sodium hypochlorite, which when mixed with ethanol or isopropyl alcohol, produces chloroform, hydrochloric acid, chloroacetone, and dichloroacetone. These chemicals could damage the nervous system, lungs, skin, eyes, liver, and kidneys. Chloroform exposure in high levels may result in death, while lower levels lead to dizziness and nausea.

  • Vinegar and Hydrogen Peroxide – Mixing vinegar with hydrogen peroxide produces peracetic acid. While parasitic acid makes an excellent disinfectant, it can irritate the eyes and nose, and cause a chemical burn. Peracetic acid also corrodes metal and can tarnish plumbing fixtures.

  • Baking Soda and Vinegar – Alone, both of these items work great for certain cleaning situations, mixed. However, they form mostly carbon dioxide and water.

  • Bleach and Ammonia – It’s pretty much common knowledge that these two items should never be mixed but, it’s worth mentioning again. When mixed, they form toxic chloramine vapors and poisonous hydrazine. Chloramine can burn the eyes, and if breathed in, will wreak havoc on the respiratory system. It can also cause internal organ damage. Hydrazine, another hazardous chemical, forms when the mixture contains a significant amount of ammonia. Hydrazine is not only toxic but also potentially explosive.

Measuring Chemical Solutions

In general, people measure fluids by volume (in teaspoons, ounces, or in milliliters), for example. Unfortunately, this method does not work when measuring chemicals, as different substances have various densities which are also temperature dependent. Plus, obtaining accurate measurements by volume can be difficult, especially when dealing with small quantities. The correct way to measure chemical solutions is by weight. Weight does not change with temperature and measuring by weight provides the most accurate measurement.

How to Mix Chemicals

When mixing two chemicals, the milder substance should be poured into the container first. This way, if splashing occurs while subsequent chemicals are added, it will be the milder chemical that splashes. Also, mixing an acid or base with water will likely cause an exothermic reaction. The mixture needs constant stirring to evenly distribute the heat. If not stirred enough, it could heat rapidly and boil any water in the solution.


Many chemicals can be harmful to the eyes or produce deadly fumes. Therefore, proper procedure should always be followed, and appropriate safety equipment should always be worn when mixing chemical solutions. At the very least, this means eye protection and a quality respirator mask. Anyone working with chemical solutions should also familiarize themselves with the materials Material Safety Data Sheet (MSDS).

Companies that manufacture hazardous substances produce a Material Safety Data Sheet (MSDS). The MSDS provides users and emergency personnel with procedures for handling a particular substance. The MSDS also includes information such as the chemicals physical properties, toxicity, reactivity, and any other necessary information in the event of an emergency.

The Lawton Brothers

As a leading distributor of janitorial supplies, the family-owned Lawton Brothers understand the need for handling chemicals correctly. They’re committed to a greener future and have over 60 years’ experience in the manufacture of high-quality cleaning products. Lawton Brothers also offer training programs that focus on improved commercial cleaning methods and productivity. All this, coupled with the fact that the Lawton Brothers offer expert equipment repair, makes them Florida’s premier supplier of janitorial supplies, support, and equipment, since 1946.

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