Friday, 28 December 2007

Factor 30

I've mentioned sunscreen earlier in this Blog. It is such a part of the way of life here that one takes it for granted - almost. My everyday large container of Factor 30 ran out. A replacement was required. Like most things in our modern consumer society one is not spoiled for choice. By the time I thought of which one I might need I was in the pharmacy. A decision was needed. Firstly choose your factor. I chose 30. Family or Sport? The label said that Family lasted for 2 hours and Sport for 4 hours. Why would anyone choose Family when they are the same price. UVA or UVA and UVB (why make UVA only if both are required?). Cream or Milk? Yes really! And so it went on. Price hardly came into it. I chose a 500ml pump action Sport Milk for $29 (reduced from $39. Seemed like a Good Idea.

A few days later something cropped up which made me think that I ought to know a bit more about sunscreens. What, for example is SPF and what is the significance of the Factor number? Apart from knowing that it stood for Sun Protection Factor and that the higher the number the "better", I was totally ignorant.

In the UK we tend to be very blasé about sunscreen and even in New Zealand there s a remarkable amount of ignorance.

The SPF (sun protection factor) gives one a rough estimate of how long one can stay in the sun without burning which is 10 times the time it would take that person's skin to start turning red. For example an SPF 15 sunscreen will protect someone who burns in 10 minutes 15 times additional protection or 150 minutes. SPF starts at 2 and the new sunscreens will offer Factor 60 and will be able to handle both UVA and UVB rays easily.

SPF only applies to UVB protection.

A water resistant sunscreen will remain unchanged after 40 minutes of water exposure. A water-proof sunscreen will remain unchanged after 80 minutes of water exposure.

It takes one ounce of sunscreen to cover the body. Thus an 8 ounce bottle of sunscreen will be used up in four days of total body application. (How old is your bottle of sunscreen at home?).

So now you know!

1 comment:

  1. While it is clearly useful to know about sun cream, it does really require the sun to appear at some point. Something I didn't really do this year in Sheffield. Hopefully next year will be a bit warmer.