What “Kills 99.9% Of Germs” Means? Find Out Here

Do you know what does “kill 99.9% of germs” written on cleaning products actually mean?

It is becoming more and more common to see people at the shops reading through labels of food products. You certainly heard about how ingredient X or Y is bad for your health or the other way around. But why do we do this with food and not with cleaning products? It’s easy to think about the food we consume, but it is easier to forget about the surface we are preparing our food on! How regularly do you disinfect your kitchen countertops? Or chopping boards? Or even your sink! We clean these areas with products that we barely know or understand!

Why Is It Complicated?

Well, it’s easy to get lost. The number of cleaning products available on the shelves nowadays is overwhelming. And even more, is the number of chemicals with complicated names in them. These products always make bold claims on their labels, like: “kills 99.9% of germs!”. Usually, such claims are always followed by a tiny asterisk, aren’t they? How many of us have read these labels to understand what this information mean? Or do the labels even have such explanations??

Back To The Basics! What Are Germs?

The term “germs” refers to the microscopic bacteria, viruses, fungi, and protozoa that can cause diseases.

These are all examples of common germs found in the average household. Invisible to the eye, these are threats that can make you and your families sick if not addressed properly!

Different Cleaning Products

I know what you are asking yourself now: “If I buy a product that kills 99.9% of the germs, then I’m good, right?”. Well, not quite! You see, there are three categories of cleaning products 1 :
Cleaning products: remove dirt and organic matter from surfaces using detergents;
Sanitisers: kills only bacteria using chemicals;
Disinfectant: kills bacteria AND viruses using chemicals.

Simple enough, right? Well, fasten your seatbelt.

Down The Rabbit Hole

Thanks to loopholes, manufacturers can use this “kills 99.9% of germs” very loosely. That means that if the product is efficient against at least one type of germ, it can make that claim. Therefore, if a product is effective against E.coli for example, but does nothing against Salmonella, it can still claim it “kills 99.9%” of germs!

Even worst than that is the fact that many products don’t even have any information on the label about which germs they are actively effective! 2

Read The Labels

Each product has its usage instructions, with minor details that do make the difference. It’s imperative to read the labels before using each product!

Here are some examples of product labels.

The Dettol Surface Cleanser is one of the most comprehensive disinfectants available in the market. This product is the main product used by Springify Cleaning!

As the label states, there’s a 10 minute wait for total disinfection of the cited germs.

Pine Cleen is one of the most well known and used disinfectants, but it is only effective against Staphylococcus and E.coli.

This is proof that even the same brand has products for different germs. This antibacterial disinfectant from Dettol is effective against P. aeruginosa, S. aureus, E. hirae and E.coli

Bad Example

Ajax is great as a multi-purpose cleaner, and it carries a seal of “kills 99.9% of germs”, but it does not inform any bacteria or virus that it is effective against.

The package says to access Colgate Palmolive’s website for more information. After about 15 minutes of looking for product information, all I could find was this pdf with the ingredients and its purposes.

Without clear information on which germs the product is effective against, I would never buy or recommend it for disinfecting purposes.

How Fast Does Disinfectants Kill Germs?

It usually takes from 5 to 15 minutes for disinfectant products to kill bacteria and viruses on a surface. Spray the product on the surface and let it sit according to the label instructions and then wipe the product off with a damp cloth. Don’t be fooled, spraying and wiping won’t kill germs on surfaces.

What About That 0.1%?

It’s a huge legal risk for companies to make claims of a 100% disinfection. If a surface shows the presence of that bacteria during tests, the company could be in legal jeopardy. Therefore they use 99.9%, allowing for legal safety. Moreover, germs are usually harmless, and most of them already live inside our bodies. Even though some can be harmful, you don’t need to be scared, even by the 99.9%.


So in short, are products that say they kill 99.9% of bacteria effective? Yes and no. They are effective against the germs described on the label (or on the manufacturer’s website), but not against all germs!

Maybe it’s time we start reading all labels in the supermarket after all!

Other Posts You May Like