The truth is, it depends. If you mostly work in the basement, where the sole source of natural light is filtered through a tiny 5x7 inch window, if any, the answer would be a clear no. If you work in the middle of a clear dome, under the direct sun, with little to no shade in the form of ceilings, roofs, or clouds between you and the light, the answer is yes.
Many continue to be sheltered in place as the pandemic wears on, and as reports of a new strain of the virus have started to emerge, new lockdowns restrictions have been imposed in various cities, further lengthening our stay indoors. Many of our routines were shaken up towards the end of the first quarter of 2020, where instances of sun exposure, such as in our commute to and from work, or our mid-day excursions, have been reduced or altogether removed.
Almost a year into this shared experience, it may well be that many have adjusted their work-life, family-life, and everything in between, to this extended stay-at-home order, and along with this their skincare regimen.
Living in a tropical country close to the equator where sunlight is available for 50% of the day, one cannot stress enough the importance of wearing sunscreen for skin health, overall reduction of skin concerns like melanoma, hyperpigmentation, and hastening of signs of skin aging which is associated with UVA rays. On top of that are more physically irritating and dangerous concerns caused by UVB rays such as sunburns (erythema), and production of melanoma, which is a form of skin cancer.
However, many have been wondering if it’s still necessary to wear sunscreen, what must have already been a daily staple in our regimen pre-pandemic.
Two factors affect whether you still need to use UV while you’re indoors: 1) how susceptible your skin is to UV damage, and 2) how much UV you’re exposed to.
Many have also been wondering if sunscreen can protect us from blue-light coming from our devices and phone screens, and the answer is that it will not. No form of sunscreen can do so, and neither does it need to because the truth is, our screens cannot produce enough blue light to make a difference. We can talk about this in another post if you’re interested, just shoot us a message in the comments below!
Back to the topic of UV, if you find yourself indoors where your exposure to sunlight is through diffused light, meaning reflected UV rays through glass windows, or other objects outside that reflect light on to you, a very rough guide to help determine how much UV you’re getting would be to assume that if you’re directly by the window and there are no trees or buildings, you receive approximately 50% sky view, meaning you receive roughly 50% of the diffused UV, the rate of which decreases exponentially the further you move away.
Moving 60cm away, gives you 29% of the diffused UV, and 120cm away from the window gives you 14%, and 240cm gives you 5%.
If there are objects like trees or other buildings blocking your direct view of the direct sky, these reflect less than 10% of the diffused UV.
Another thing that normally stands between us and the sun is GLASS. This blocks 100% UVB rays, and about 1/3 or ¼ of UVA rays.
UV Index, which is the measure of how much erythema or sunburn-causing UV you’re getting at a particular location, at a given time of day. This changes as the day wears on and is a useful tool to refer to as you plan your day out. This value normally starts at 1 around 7am and peaks with a UV Index of 12 in the middle of the day, then tapers off as the night approaches.
UV Indexes of 1-3 are considered within the safe range, and anything from 4 upwards recommends sun protection in the form of long sleeved tops, hats, and sunscreen, if you’re staying outdoors under the direct sun for more than 5 minutes.
We know, it's a lot to consider just to stay protected, but these are just tools and guidelines to help make a more informed decision. In short, if you don't intend to stay near the window, won’t be spending too much time outdoors, or know you won’t be sweating as much throughout the day, it may be safe to assume you won’t need to wear any sunscreen.
If you like this, have any questions, or are interested in more content like this, let us know in the comments below! Credits to Michelle Wong’s Lab Muffin Beauty Guide.