Yes, you may. Please manage your time so that you are able to complete your new calendar year projections when they come due.
The day I got my whistle (Clarke D) it was banned by my daughter to the car, where I play it while sitting at stoplights. This has the fringe benefit of lower stress levels: I don’t chomp at the bit so much if I whistle while I wait.
Also, it’s really awesome when I’m able to play it elsewhere. My band practices in a large church auditorium. I’m usually playing keys, but this week I whipped out my whistle for a couple of songs. WOW - I sounded better than I ever thought I would!
I don’t recommend playing at stoplights. I have come to appreciate a good traffic jam and road construction. I’ll put the car in park and play. A slow drive thru line is fun too.
November 2, 2008
My wife and I took a hike up a mountain, spread out a beach towel on a nice flat rock, opened a bottle of wine…
…and I played my Clarke D. 
We got some interested looks from other hikers.
It’s amazing how efficiently you practice when you know you only have between 20 and 120 seconds in which to play. 
I think I know what you mean, though. For safety reasons, I’ve started to watch my rear-view mirror, and not play until I know I won’t be rear-ended with a whistle in my mouth. But a traffic jam and road construction? I must be one of the few Americans for whom that’s a less-than-yearly event. Envy me.
One time I played in a garage and it sounded pretty cool.
I played cornet in a public lavatory for the Lord Mayor of London once…
I’ll be playing in a wide open Vermont field this weekend.