Centro de Documentacion de Fundación MAPFRE - The Effect of microscope graticule size and counting rules on the estimation of airborne fibre numbers using the membrane filter technique

MAP20071017544

The Effect of microscope graticule size and counting rules on the estimation of airborne fibre numbers using the membrane filter technique / J.W. Cherrie

Sumario: This paper has examined the graticule effect in more detail when counting rigurously, using a wider range of graticule sizes and two counting rules (ARC and NIOSH) for fibres crossing the graticule boundary. The results have confirmed the absence of a significant effect with graticules larger than ca 100 microm dia. but noted an increasing bias when using the ARC rules as the graticule size was reduced from 100 to 20 microm. This bias appears to be caused by a tendency of the observer to count more fibres crossing the upper section of the graticule than the lower

En: The Annals of occupational hygiene. - Oxford [etc.]. - nº 2, 1984 ; p. 229-236

1. Higiene industrial . 2. Contaminación atmosférica . 3. Control de la contaminación . 4. MFM . 5. Muestreador . 6. Muestreos . 7. Fibras . 8. Métodos de análisis . I. Título. II. Título: The Annals of occupational hygiene.