For fluorescent lamps, it is 3 hours "on" per switching.
I presume CFLs are the same, but I don't know that for sure.

I think that for CFLs it effectively assumes for the survival factor 2
hours if the start-up time is less than 0.3 seconds. That's due to
improve to 1 hour. This and a lot else about required perfomance is
specified for CFLs in Annex II, Table 4 to Commission Regulation (EC) No
244/2009. And yes I am very sad that I could be bothered to look up the
source.

--
Robin
reply to address is (meant to be) valid