The document summarizes three studies conducted in Ireland that measured air pollution from secondhand smoke (SHS) in exempted workplaces under Ireland's 2004 smoke-free law. The studies found:
1) Ultrafine particle levels in psychiatric hospitals averaged 130,000 per cm3, over 45% higher than pre-ban Dublin pubs. PM2.5 levels were similar to pre-ban pubs.
2) In prisons, 44% of non-smoking officers had exhaled carbon monoxide levels indicating light or heavy smoking, showing significant workplace SHS exposure.
3) Nursing homes that allowed smoking had PM2.5 levels eight times higher and nicotine levels four times higher than smoke-