Most everyone is accustomed to seeing SPF ratings displayed on sunscreen bottles, but have you ever taken the time to actually understand what each one means? Well, essentially, Sun Protection Factor (SPF) is something that provides a guide to the user on how long it would take for you skin to burn while weather e.g. Sunscreen SPF 50 means it will take fifty times longer.
Notice there that we said ‘longer’ instead of ‘not at all’, because there’s no such thing as a product that will protect you against 100% of all UV rays.
How Long Does It Normally Take to Burn?
Believe it or not, it can take as little as 11 minutes for those first signs of redness to appear on unprotected skin and when they do, you know that discomfort is not far behind. So, if an sunscreen SPF 50 is said to extend the time burning takes, you’re looking at 50 x 11 minutes, which equates to 550 minutes (just over 9 hours in direct sunlight).
There is a caveat to that statement though, as it’s going to require that you reapply that same sunscreen once every two hours for the whole duration. So, within those 9 hours of exposure, you’ll need to have fully reapplied your sunscreen 4 or even 5 times.
You Don’t Want to Actually Burn Though, Right?
The figures stated above relate to the amount of time it takes to suffer sunburn, so you shouldn’t be saying “well, I can stay out for 9 hours with this on!”, because you’ll still end up being burnt!
Just because it’s taken 9 hours instead of 11 minutes, the result is the same, so while using your SPF 50, you must also practice sun safety so that you’re not damaged by UV rays at all!
Focus On UV Protection Too
Another important aspect of sunscreens is UV protection. This is the amount of UV rays that the SPF-rated sunscreen is able to safeguard you against. So, In terms of UV protection, this is how the SPF ratings break down:
- SPF 15 is going to block 93% of of UV rays
- SPF 30 protects you from almost 97% of UV rays
- SPF 50 blocks 98% of UV rays
You might be surprised to see that the SPF number bears little or no relation to the amount of UV protection it provides. Logically speaking, you might assume that SPF 15 offers ½ the UV protection of an SPF 30, but the truth is that there’s only around 4% difference. Moreover, a sunscreen SPF 50 only blocks 1% more than an SPF 30.
A Sunscreen SPF 50 Alone Is Not Sufficient For Sun Protection
Your takeaway from reading this article should be that you can’t just whack on an SPF 50 at the start of the day and expect to be protected until dusk.
Staying protected from the sun involves reapplication every 2 hours, avoiding the most intense hours of the day (10 am – 4 pm) if you can and don’t assume that the SPF rating relates to the amount of time you can spend in direct sunlight.
Combine this approach with wearing loose-fitting clothing and you’re much more likely to avoid the misery that comes with suffering sunburn. Now, that’s worth focusing on.