Don't forget to pack your common sense

A nice example of why climbing up onto the active dome is not risk-free. These two videos are from people that climbed and were perhaps a little lucky: the first during an eruption and the second of walking into the crater. You can argue the wind is important but eruption sizes vary from event to event and aren't predictable time-wise. For example (pic) here and (video) here you can get a good idea of what's really going on inside that cloud. Avalanches can occur on any side of the dome, not just where the active lava flow/s are. People are occasionally killed here, even when they're not on the dome.