Search

P2/N95 respirators or filtering facepiece respirators may not have the same pass rate on quantitative fit testing. The aim of this study was to investigate the pass rate of four commonly used filtering facepiece respirators in Australian healthcare providers. The secondary objectives included assessing the ease of donning, doffing and comfort of wearing these four filtering facepiece respirators for more than 30 minutes. A multivariable analysis was also conducted to assess if certain variables (e.g. age, sex, body mass index, ethnicity, facial width and length) were associated with passing or failing fit testing. We conducted a prospective observational study of 150 hospital staff who presented for fit testing in a metropolitan hospital in Victoria, Australia. The order of the four filtering facepiece respirators being tested was randomised. A Cochran's Q test was used to test the global null hypothesis that all four filtering facepiece respirators being tested have the same pass rate. A difference in pass rate was found between the four filtering facepiece respirators that were tested (P < 0.001). The 3M™ Aura 1870+ (3M Australia Pty Ltd, North Ryde, NSW) had the highest pass rate (83%) followed by the 3M™ 1860 (3M Australia Pty Ltd, North Ryde, NSW) (61%), BSN ProShield™ N95 (BSN Medical, Mulgrave, Victoria) (55%) and the BYD DE2322 N95 (BYD Care, Los Angeles, CA, USA) (44%). There was also a difference in the ease of donning, doffing and comfort. Therefore, healthcare facilities that perform fit testing should take these factors into consideration when designing an effective respiratory protection programme. [ABSTRACT FROM AUTHOR]

We report on the discovery of a 25.5-min superhump period for the suspected helium dwarf nova system KL Draconis in a high state. The presence of superhumps combined with the previously observed helium spectrum and large-amplitude photometric variations confirm that KL Dra is an AM CVn system similar to CR Bootis, V803 Cen and CP Eridani. We also find a low-state photometric period at 25.0 min that we suggest may be the orbital period. With this assumption, we estimate q=0.075 , M[sub 1]=0.76 M[sub ⊙] and M[sub 2]=0.057 M[sub ⊙] . [ABSTRACT FROM AUTHOR]