Thousands of Scottish licensees face heavy new costs to bring their toilets up to scratch as part of measures in the new Licensing Act.
Under the new system - effective from next year - businesses who need to upgrade toilet facilities face not knowing whether they'll be able to trade in a year's time.
Applications are being approved on a 12-month's grace basis, which can be extended to 24 months, if the council reckons toilet facilities aren't adequate for the numbers using a bar.
Some outlets could lose their licences altogether if they fail to bring in improvements, or face a wait of up to two years to find if they will gain a permanent licence.
Others - including older properties which can't accommodate toilets because of space constraints - may be allowed to carry on as before, if they're judged to have done their best.
The move has been sparked by conditions in the Act which give council building control departments the right to object to licences on grounds including inadequate toilet facilities and poor safety exit provision.
John Loudon, consultant with Lindsays solicitors, predicts some pubs could be forced to shut, if they can't juggle the toilet and safe exit numbers to satisfy the council.
He said: "You potentially have the double whammy of sorting the sanitary accommodation for 'x' people, while finding the escape route can only cope with 'x' minus - and vice versa."
Bars forced to reassess toilet and escape route provision include The White Hart in Edinburgh's Grassmarket, the A-listed oldest pub in the city, along with many other traditional pubs.
Lawyer Joanna Brynes of Andersons solicitors said Glasgow licensing board had taken a "pragmatic" approach but that significant numbers of businesses would face problems.
"The board may accept older premises can't install extra facilities," she said, "but there's still the cost of paying somebody to tell them that, and in detail."