campaign grew from a week-long event in 2006 to a month-long event in 2007 and 2008 and then a three-month event in 2009. in the midst of expanding the campaign, the Singapore government managed to introduce creative means each year to spread OSH messages. for example, in 2007 the campaign's cornerstone was a safety-pledge drive. more than 50,000 people from all walks of life pledged to do their part to improve OSH conditions. this broke Singapore's book of records for the largest number of pledges collected, and the compilation of the pledges formed the largest book ever produced in Singapore. in 2008, the government rolled out a 40-foot container mobile exhibition to deliver OSH awareness workplaces and into housing estates. over the years, the government has also increased the visibility of its publicity drive by using advertisements at bus, mobile advertisements on buses and radio to spread OSH messages.