Prisoners face random breath-tests in a bid to cut down on boozing in jail. Governors will get the power to check inmates amid fears drinking is on the rise behind bars.
Alcohol is banned in prison, but there is a widespread trade in illegal hooch brewed inside. Spirits and home-brew beer kits are also regularly smuggled in.
A senior jail worker said: "The tests are expected to come in next year as part of the first strategy to deal with alcohol in prisons.