How Small is a Nanometre?
Posted 4 years ago
LifeSaver water purifiers make the process of turning dirty water into safe drinking water look very simple. However explaining the way the technology works can be challenging. It’s impossible to explain how LifeSaver’s ‘hollow fibre membranes’ purify water without referring to the size of the pores in the membrane. The membrane pore size is crucial to keeping people safe and it’s the part of our products that catapults our advanced water purifiers ahead of the plethora of basic water filters on the market.
Pores are the small holes in our membranes which allow water to pass, but which physically prevent larger elements passing through. i.e a tennis ball cannot pass through the small holes in a tennis racket, but rain droplets would.
If viruses or bacteria were smaller than the holes in our membranes, they would freely pass through, therefore it’s of vital importance we know our membranes are of the best, most consistent quality possible. With a pore size of approximately 15 nanometres, the pores in our purifiers are comfortably smaller than all waterborne microbiological contaminants known to harm humans.
However, it’s when we start talking about the size of these pores as being approximately 15 nanometres or 0.015 microns, that we begin to get confused looks from our audience!
A nanometre is mind-blowingly small, so the following stats are just an attempt to give some perspective*:
- 1 micron is 1000 nanometres
- 1 nanometre is 1 billionth of 1 metre
- Human fingernails grow at a rate of around 1 nanometre per second
- A single strand of human DNA is 2.5 nanometres in diameter
- A human hair is 100,000 nanometres thick
So now you have some perspective, you can appreciate a little more just how small our 15 nanometres pore size is!
For comparison, most of our competitors who also use hollow fibre membrane technology have a pore size of 100 or 200 nanometres. Whilst these membranes would protect users from most bacteria, which range from 300 – 5,000 nanometres in diameter, they won’t protect users from viruses which range from 20 – 200 nanometres in diameter.
Essentially, if a product claims to have a pore size of 0.1 or 0.2 microns (100 or 200 nanometres) it is just a water filter, it isn’t a water purifier because it can’t remove viruses. Only products which claim a pore size of 0.02 microns (20 nanometres) or smaller are water purifiers and will protect against all microbiological contaminants. However always ensure the appropriate independent testing has been done to verify these claims!
Read more about the importance of testing here.
All LifeSaver products use the same hollow fibre membranes, which means they are all as effective and safe as each other. The only difference between each of our products is how much of the membrane can fit inside them. The more surface area of membrane used in a product, the more litres of water it will purify before it will need replacing. Our LifeSaver Liberty bottles will purify up to 2,000 litres, while our LifeSaver Jerrycans will purify up to 20,000 litres. This is because the Jerrycans have 10x more hollow fibre membrane surface area than the Liberty bottles.
*Stats taken from https://www.nano.gov/nanotech-101/what/nano-sizeBack to News