In just over a week, a sneaky fag in the staffroom will be illegal as well as inadvisable. Come July 1, England will become the fourth and final country in the UK to ban all smoking in enclosed public spaces - and that includes schools.
We've known for decades that smoking seriously damages your health, but its impact on others has only been proven relatively recently. A review carried out in 2004 by the Scientific Committee on Tobacco and Health estimated that non-smoking adults exposed to second-hand smoke were 24 per cent more likely to develop lung cancer, and 25 per cent more at risk of heart disease than other non-smokers.
Although teachers are not exposed to second-hand smoke in the same way as, say, pub landlords, they are vulnerable at home. Professor Konrad Jamrozik, formerly of Imperial College London, has estimated that exposure to second-hand smoke in the house causes around 10,700 deaths a year in the UK.
"We recommend that non-smokers find and keep at least one area or room in the home smoke-free," advises Kate Spicer from Quit, a charity that helps smokers give up.
Those who cannot escape the smoke are exposing themselves to some 50 known substances that cause cancer, including benzene, which is found in petrol fumes, and arsenic - also used in rat poison.
Like all other businesses, schools were sent free No Smoking signs in April. These will need to be displayed at all public entrances to enclosed buildings and school vehicles when the ban begins.
"This is the minimum requirement," says Ian Gray of the Chartered Institute of Environmental Health, "but local authorities may want to go beyond that, for instance making the whole school campus smoke free."
In addition, the legal age for buying cigarettes will rise from 16 to 18 years old in England and Wales on October 1. Ian hopes the changes will make smoking less socially acceptable and to help more people kick the habit.
For more information or signage, visit: www.smokefreeengland.co.uk
IMMEDIATE EFFECTS OF SECONDHAND SMOKE
* Eye irritation
* Cough and sore throat
* Dizziness and nausea
* Decline in lung function for those with asthma
* Reduced coronary blood flow after 30 minutes exposure