00878nam a22002537a 4500 D0001B000485 DOH 20210205145302.0 210205b ||||| |||| 00| 0 eng d 9241544961 rda World Health Organization Determination of airborne fibre number concentrations : a recommended method, by phase-contrast optical microscopy (‎membrane filter method)‎ Geneva : WHO, 1997. 53 pages. rdacontent text rdamedia unmediated rdacarier volume Air Pollutants, Occupational analysis Environmental Monitoring Microscopy, Phase-Contrast methods https://apps.who.int/iris/bitstream/handle/10665/41904/9241544961.pdf?sequence=1&isAllowed=y nlm BK 2720 2720 0 0 nlm 0 0 DOHCL DOHCL WHOPub 2021-02-05 0 WA 450 DET 1997 D0001B000485 2021-02-05 00:00:00 2021-02-05 BK 0 0 nlm 0 0 DOHCL DOHCL WHOPub 2021-02-05 0 WA 450 DET 1997 D0001B000486 2021-02-05 00:00:00 2021-02-05 BK