I’m happy to report that, according to the UV meter in my wrist watch, the UV Index at window seat 12A, with the sensor pointing towards the sun at 11 am on 4 October as we landed in Hong Kong this morning was, wait for it …… zero. I’d heard the aeroplane windows don’t tranmsit UV-B, but this was a nice confirmation. Though I doubt if the UVI outside was much above 3 anyway. The surface of the Earth was invisble from 30,000 feet. Still, I wouldn’t advise spending too long in the sun in HK. Far too hot, for one thing.