30 seconds of direct sun exposure directly after fraxel treatment on the way to car?

I think it's wonderful that your venture into self-care with Fraxel has made you so aware of the dangers of sun exposure and so diligent about avoiding it. This is an additional good outcome to the benefits you'll receive from your rejuvenation. Although the sun can indeed damage the skin in brief periods if it is very intense, between the limited amount of time it took to get to your car and your shading your face, I think you'll be fine. However, please remember that even in the car your skin is exposed to UVA and UVB rays. So please wear sunscreen even when indoors or driving and be sure to pack a hat so that you can walk the parking lot confident that your skin is protected. Please consult your board-certified dermatologist to get more tips on how to protect your skin from sun exposure.

From your description, it is very unlikely that you will have hyperpigmentation after your brief exposure. Keep in mind, this type of laser takes a series of treatments and with usually needs a combination approach to have the best results. I recommend lasers with microneedling and prp to improve outcomes. Also, in my practice we are very particular about pre and post skin care with patients.  This is customized to the persons skin type and condition treated. See an expert. Best, Dr. Emer.

Thank you for your question. There is nothing to
worry about as this short duration to sun exposure would not cause
hyperpigmentation or have any effects on your treatment. Just make sure to
avoid long term sun exposure. All the best!