WHY QUATS and NOT BLEACH?
Quats are Quaternary ammonium chloride compounds. Basically, bleach burns the microbe through oxidizing. It also burns everything else like eyes, skin, lungs, clothes etc.
Quats, though very expensive, are much safer. They zap the microbe with positive charge. All microbes are negatively charged so the positive charge is like a bug zapper to them. (View Source)
WHAT ARE THE DIFFERENCES?
Bleach is a common household name for a solution of sodium hypochlorite and water.
Sodium hypochlorite, in its pure form, is a water soluble, yellowish liquid that contains about 12% chlorine and is an extremely powerful oxidizing agent.
It will corrode or destroy most metals, react with acids, peroxides, and many other chemicals to produce toxic chlorine gas. Bleach will dissolve paper, cloth, and many other organic materials.
Even in the 5% household strength, bleach is still a potent oxidizer and disinfectant with very high alkalinity. Caution must be used when working with bleach. Even in diluted form the fumes can produce severe irritation to the respiratory system.
Skin contact can result in mild irritation to burns. Prolonged eye contact can cause permanent damage.
Bleach contains NO cleaning agents.
Quat is the common name for quaternary ammonium chloride compounds of which there are about 300 varieties all with varying anti-microbial efficacies. Quats are generally surfactants with cationic (positive) charges.
Due to their surfactant make-up, quats contribute cleaning power to their formulas. These products are low in toxicity and corrosivity making them user friendly and simple.
While the advantage of bleach is ultimately the inexpensiveness to use, the rest of the variables are all disadvantages. Bleach is highly corrosive, contains toxic fumes, dissipates quickly, bleaches most fabrics, causes irritation to the eyes and nose, has no cleaning ingredients, dulls floor tiles, and damages floor finish and grout. Bleach is dangerous if mixed with many chemicals and cleaners.
On the other hand, the disadvantage of quat is the price in comparison to bleach. Quat can also have reduced activity in the presence of soil.
However, the advantages of quat is what make it the winner. Quat has excellent wide spectrum germ kill ability, film forming residual, low toxicity and corrosivity, simple to use, good shelf life, works in a variety of pH ranges, highly concentrated, no odor, and safe on mostly all surfaces. There are neutral formulas that will not dull floor finish. Quat will not change the taste or odor of food. It is the choice disinfectant for most hospitals and health institutions.
Quats are Cationic (positively charged) ions that disinfect surfaces by binding to the negatively charged membranes of germs to break down their outer cell wall. Opposites attract. Quats are positively charged.
Use the EPA’s List N tool to find COVID-19 Disinfectants (Here)
Additional resources: How Quats Work