The Chartered Institute of Environmental Health (CIEH) has written to the Prime Minister urging him to back plans for an Approved Code of Practice (ACoP) on smoking in the workplace.
The move comes as the trade continues to lobby for pubs, which are already covered by the voluntary charter on smoking in pubs, to be exempted from the code.
The CIEH said last week that it had been prompted to write to the government following rumours that the hospitality trade was winning its fight.
Graham Jukes, director of professional services at the CIEH, said: "We are concerned that progress on this ACoP is faltering owing to pressure from the hospitality sector.
"Measures to reduce the impact of tobacco smoke on workers can be implemented at minimal cost and minimal disruption."
The ACoP recommends the use of air cleaners, no-smoking areas and ventilation and suggests a complete ban on smoking at the bar. It is aimed at protecting staff from the dangers of passive smoking but the trade fears it would not only confuse the issue for licensees but would have no phasing-in period.
This means the code could be used by staff from as early as next year to support any legal action against a licensee or pub operator over passive smoking.
The charter also recommends the use of measures to improve smoky atmospheres but is voluntary, allowing it to be phased in over the next few years.
Nick Bish, chief executive of the Association of Licensed Multiple Retailers, said: "We are still negotiating, but the power of our argument will be increased by each and every pub, restaurant or hotel that becomes charter compliant."