Do you remember starting school and the point where you started learning about TENS and UNITS? If you do then you are quite young! The point here being the word UNIT(S). It’s a simple English word but with many different interpretations once you start dissecting it. What is a UNIT and how do you describe it in different situations and for different measurable parameters?

A unit = 1. This is the most basic explanation I can give. However, if we talk about time, the question is 1 what? Well, it could be 1 second, 1 hour, 1 light year, etc. Does time have length, breadth or height or does it have period? TV presenters talk about length of time and very seldom use the word period, which is probably best suited. This has been happening for a long time….there we go again! I have lots of free time that’s why I am writing this blog……or do I have lots of free periods of time?

Another quantum: “lots” or “a lot”! There were lots of people at the taxi rank this morning….or were there many people…..or was there a large number? What about volume: 1 litre and many litres, one large volume (not easily measurable), 1 millilitre (measurable), lots of water! The same descriptors in terms of quantity may apply to many different measurable parameters.

However, at the end of the day, there are a few descriptors that are more correctly descriptive rather than vaguely descriptive (number, length, period). At the same time, why worry, we all understand what is meant during casual conversation. Scientifically though, we need to be a little more specific when speaking and writing. We need to understand exactly what is being conveyed without having to redefine words as we use them.

An interesting example in casual conversation to end off this bland topic: what is one Rand? I had asked this question at a workshop when covering a section of standard units used in chemistry. It was amazing (or not so) that not one participant could define the Rand. Can you? I then used this as an example of what a standard is and how a standard is just that…..a standard…..it does not change! And it has a UNIT. Is the Rand a standard? If not, what is the standard in this instance?

Larry Dolley