"At an altitude of 50 km above Venusian surface, the environment is the most Earth-like in the solar system – a pressure of approximately 1 bar and temperatures in the 0°C–50°C range. Because there is not a significant pressure difference between the inside and the outside of the breathable-air balloon, any rips or tears would cause gases to diffuse at normal atmospheric mixing rates, giving time to repair any such damages. In addition, humans would not require pressurized suits when outside, merely air to breathe, a protection from the acidic rain; and on some occasions low level protection against heat."
http://en.wikipedia.org/wiki/Colonization_of_Venus#Aerostat_...
Just don't fall off the edge... :)