2018.04.20 Bacteria and endotoxines

Bacterial pedagogics

400 years ago, the scot John Napier published the first logarithm tables. It then became possible to quickly and easily handle large numbers, complicated multiplications and divisions. This, of course, became a revolution for mathematics – and not least for astronomy.

The disadvantage of logarithms is that the scale is a bit far from our everyday life, which makes it difficult for us to comprehend the numbers. At Wallenius Water Innovation, we work with bacterial reduction – and bacteria are often talked about in logarithms. One then specifies the number of bacteria in a drop of water (1 ml).

But do we really understand the difference between, for example, 10^7 and 10^5? Sometimes it can be difficult to understand that 10^5 is only 1% of 10^7. To explain this in an educational way, we have compiled a metaphore below, replacing the water drop with Sweden and every inhabitant in Sweden with a bacteria!

If Sweden's inhabitants were bacteria...

The number of bacteria is measured and is usually given in logarithms, which makes it difficult for us to understand the actual difference.

10^7 = Number of inhabitants in Sweden
10^6 = 2/3 of the population in Stockholm and 10% of the population in Sweden
10^5 = Number of inhabitants in the city of Norrköping and 1% of the population in Sweden
10^4 = The number of residents in Säter and 0.1% of the population in Sweden
10^3 = The population of Bjurholm (Swedens smallest municipality) and 0.01% of the population in Sweden
10^2 = Half of the inhabitants at Fjärås station (Kungsbacka municipality) and 0.001% of the population in Sweden
10^1 = The number of people recommended in a relatively spacious elevator and 0.0001% of the number of inhabitants in Sweden
10^0 = Equal to you and 0.00001% of the population in Sweden

In other words, if you reduce the bacterial content by 10^7, you lose 99.99999% of the bacteria.

On our website, we regularly publish interesting articles, tips and observations about process fluids from an objective perspective.

If you are interested in reading more about our work, please visit one of our customer cases here. 

E-book: UV light

Jan Östlund
Jan Östlund

Jan har över 20 års erfarenhet av processvätskor inom den metallbearbetande industrin. Han har stor kunskap om processvätskans kritiska funktion och även om dess miljörisker.

Jan has over 20 years' of experience from process fluids within the metalworking industry. He is highly knowledgeable on the process fluid's critical functions and its environmental impact as well as the total cost of ownership related to process fluids and the savings that can be achieved making the right choices.

Jan hat über 20 Jahre Erfahrung mit Prozessflüssigkeiten in der Metallverarbeitenden Industrie. Er ist sehr gut informiert sowohl über die kritische Funktion der Prozessflüssigkeit als auch über seine Umweltrisiken.

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