Year 8 pupils from Cyfarthfa High School in Merthyr Tydfil have designed posters to try and stop people smoking outside their hospitals On a crisp afternoon a group of school children stand outside Prince Charles Hospital holding their handmade no smoking posters. As ambulances pull up outside the Merthyr Tydfil A&E department, the 10 and 11 year-olds watch as patients and visitors light up, puffing smoke into the air.