1. Breathing system filters for anaesthetic and respiratory use – Part 1: salt test method to assess filtration performance (BS EN 13328-1:2001);British Standards Institution,2001
2. Measuring the filtration performance of breathing system filters using sodium chloride particles;Wilkes;Anaesthesia,2002
3. Specification for particle filters used in respiratory protective devices (BS EN 143:1991);British Standards Institution,1991
4. Statistical methods for assessing agreement between two methods of clinical measurement;Bland;Lancet,1986
5. Factors affecting the filtration performance of breathing system filters;Wilkes;Br J Anaesth,2000