The majority of people visiting Switzerland's cafes, bars and restaurants are bothered by cigarette smoke, according to a study by the Federal Health Office.
The results coincide with the launch of a campaign by Gastrosuisse, the restaurant and hotel owners' association, to provide smoke-free zones in eating places.
The study found that the number of people affected by passive smoking had fallen from 54 per cent in 2001-2 to 47 per cent in 2004, partially thanks to an improvement at the workplace.
But more people were affected by smokers lighting up when they went out to eat or drink.
In 2001-2, smoke in bars and restaurants was a problem for 49 per cent of respondents. By 2004 the figure had risen to 56 per cent.
Gastrosuisse called for a big increase in smoke-free seating but said this should be left up to the individual establishment and not be enforced by law.
Florian Hew from Gastrosuisse told swissinfo the national campaign was a response to changing trends in society and increased discussion of the problem of passive smoking.
He said the idea was to motivate businesses to create clearly defined smoke-free areas for the benefit of customers.
Gastrosuisse suggests use of the designations "smoke-free", "smoke-free room", "smoke-free times" and "smoking" in restaurants and cafes.
Freedom to decide
The association wants to see bars and restaurants adhere to a voluntary code of conduct, and says a total smoking ban is not necessary.
"It would harm restaurants, hoteliers, guests and the general public to have restrictions placed on them by the federal government. People should have the freedom to decide these matters for themselves," Hew said.
He added that Gastrosuisse was hoping that a higher percentage of establishments would offer non-smoking rooms, smoke-free zones or a ban on smoking during meal times.
The national campaign got underway on Friday as the Ticino parliament prepared to debate a total smoking ban in restaurants and bars across the southern canton.
It was due to decide this week whether to approve the ban, announced last year by the cantonal government.
The Gastrosuisse project was launched first in canton St Gallen to test the response of restaurateurs and the public.
"We have had positive feedback from hoteliers so far, but changing the concept of smoking in hotels and restaurants is going to take time," remarked Hew.
"It is a difficult decision for hoteliers to take because they have to take into account the different opinions of all their guests."
Gastrosuisse has 20,000 members. The non-smoking voluntary campaign is open to all members and non-members.
swissinfo with agencies
The Federal Health Office survey questioned 2,500 people aged 14 to 65.
It found that over 60% wanted smoke-free zones in all restaurants.
56% of respondents (68% of non-smokers) said they were extremely bothered by smoke in restaurants, cafés and bars.
47% complained they were subjected to smoke at the workplace.