To be on the safe side i would wear a hat/bandana to cover the transplanted area as you dont want to risk getting the new grafts damaged via sunburn.If you are without a hat i would limit the exposure to 10 mins.
Also apply a high factor sunscreen to be extra safe.
ya I would def. wear a hat. H&W told me a sunburn on the recipient area could severely damage the grafts even up to 6 months post op. Don't risk it! I'd make sure it doesn't have tiny holes on the top too (i.e. base ball cap). BTW as long as I'm wearing a hat that has zero holes in it & isn't transparent, then there's ZERO risk (to my recipient area) of being under direct sunlight regardless of time spent or even during the hottest times of the day, right?