150 Merino ?? Offer any sun protection ??

This is not scientific at all, but to me it definitely "feels" like it does.

I use the Icebreaker 150gr longsleeve (tight fit, "beast"?, whatever the cheapest version is) and when in the sun, I definitely feel as if it's protecting my skin, and keeping me cooler, almost like it's insulating it if that makes sense. I can stay in the sun exposed longer.

I also walked around Hong Kong in the height of summer once to test it out, with God knows what humidity and actually felt the longsleeves kept the heat and exhaust from the cars and buses off me. Like a layer of protection.

Likely not the info you're looking for but hope it helps.

LOTS! And it is cooler and cleaner than sunscreen! Beware of pointelle knits and worn spots. But otherwise, absolutely!

I have noticed that mozzies really dig lightweight sweaty merino though — apparently they can feed right through it. Sandflies less so. 100% DEET was liberally applied to skin…

I have "tested" 150 ish merino over and over again in the NZ (and AUS — I lived there for years) summer! Interestingly, under the hot southern sun, I find heavier weight (200-250) to be cooler.

I wore my long sleeved merino shirt (ultra light weight) while out on a boat fishing for 5 hours. Temp was about 85*F. The back of my hands got burned, my arms, shoulders did not. Felt very comfortable too.

Re mozzies, flies, etc: I've permethrined all my merino shirts, and didn't get any bites through the merino.

In my experience, absolutely! Can't back that up with any data so take it for what it's worth, just my experience. I should note that I'm also a dark skinned fellow who NEVER wears sunscreen, hate the stuff….even though I know the risks of ignoring, live in the high desert and spend many hours outside daily.

I'll wear a thin merino longsleeve top with a hoody next to skin even when it's in the low 70's for backpacking, evaporative cooling works wonders with wool in my drier climate, the sun is deterred, and my skin and body temperature stays happy always.

Merino is supposed to have a wool has a UV factor of 30+

http://www.dimples.co.nz/FAQ/Fabric+Information/New+Zealand+Merino+Wool.html

http://www.wool.com/Wearing_About-Merino_Proof_UV-Protection.htm

http://www.biomedcentral.com/1471-5945/1/6

~

I've never been burned through my merino.

The tops of my hands burned once (trekking pole use in the High Sierra), and with the pull-over style sleeves on my merino shirt, they were better each following morning of the trek. I had to cover my hands, but the merino allowed the sunburn to heal.