sade087

It's time to examine the float test for hair porosity more fully. I began looking into how the float test could give you an inaccurate result in the previous post . Elsewhere on this blog I have mentioned that this test is not very accurate. This post will show you why. To make the test more accurate, see the tips at the end of the post © Science-y Hair Blog 2 The idea behind the float test follows this line of thinking: If hair is porous, it takes on more water than if it is not porous. Therefore, porous hair might sink because it takes on water and becomes heavy. That is - the weight of the water the hair is absorbing overwhelms the power of surface tension (between water molecules) that keeps the hair suspended on top of the water. And in a sense this is not wrong but it is incomplete. But there are too many other variables in play to make this an accurate assessment of how porous your hair is by simply grabbing some hair and dropping it in a glass. Your experiment needs ...

Porosity is tricky to define because of these three things: 1) Porosity is a physical condition that belongs to an individual hair - or a portion of a hair. It is the amount of surface area with porosities - gaps and holes through which water and other things can move. 2) Porosity is a behavior or your individual hairs and your hair as a whole - how quickly does water move through any porosities present. 3) We want to use porosity to determine what to do to our hair - but all the things we do can modify our hair's porosity-behavior or even mask actual porosity. For example, sun-damaged and therefore porous hair may feel different than bleach-damaged and therefore porous hair. Or hair which is easily weighed down or low-density (thin hair) may or may not be able tolerate lots of conditioner and heavy oil applications that we usually think porous hair needs. Different porous hair has different needs. Why does porosity-behavior matter? Let's say you use a henna or cassia treatment...