Whether or not the bin is compacted, the important thing to ask is whether or not there is enough oxygen available to them. You may not be able to add as much feed at any given moment in a compacted bin than you would in a bin that still retains more air space. As the microbiological decomposition of the organic matter will quickly deplete what little oxygen is left in a compacted bin. So, adjust the type, amount and frequency of feed according to the overall condition of the bin. There are many good books but you'll find that learning through experience and through the experience of others in this community is the best resource.

i think their is enough air i mean i have not seen any worms escape except for one time but that was because i didn't have a cover on the bin.