Unorthrodox — But Will It Still Work?

You could always get some micronized titanium dioxide and just mix it in to your favourite insect repellant. That way YOU control the SPF.

Hi Allison,
How will you know when you have reached, say, SPF 30? Or 45?
Is there a known relationship between a given percentage(by weight?) of titanium dioxide in a lotion and its corresponding SPF rating?

On a percentage basis, each 1% (w/v) of titanium dioxide will add an SPF of 3-5. So a 10% concoction (ie 10 grams titanium in 100mls bug stuff) should get you SPF 30-50. It must be either emulsified in the lotion, or shaken vigourously just before use to ensure even application.

I don't like the idea of applying deet when all I need is sunblock. I use much more sunblock in the High Sierra than bug repellent. Just bring the 1 oz size of deet.

For me, the sun block lasts as long as my current 100% DEET — I usually apply both two times a day.

Problem with 100% DEET is that I still get bitten by evil black flies! Thus, the thinking out loud about switching to the repellant linked in my first post — but hoping somehow to avoid bringing and using two separate bottles/containers of lotions.

On another thread someone mentioned that citronella was what repelled black flies, not DEET. Dunno, myself.

Hi Roger:

You are correct. Even 100% DEET doesn't do much to protect against flies. The Ultrathon repellant I linked up above supposedly will.

Ben,
I'd be a little skeptical about Ultrathon protecting against Black Flies or Deer Flies; Its active ingredient is DEET at a 34.34% concentration. Maybe it has a secret, unlisted ingredient?? ;)

Tom:

The 3M Ultrathon label clearly states: "Also repels biting flies, chiggers, deer flies, fleas and stable flies"!

I mean, companies wouldn't lie to us, right? Unless there are rogue, unstable flies out there…

Everything is unstable, Ben. Entropy rules. And I'll bet that's exactly how their lawyers would defend the label in court. "Your honor, my client makes no claim as to the efficacy of his product for repelling unstable flies…". :)