Rapid estimations of diameter minus lumen
(D-L), and outer perimeter of cotton fibers (P) in
microns, as a biological fineness of Egyptian cotton
could be calculated with satisfactory levels of
accuracy from hair weight (H.W) in m/tex and
maturity ratio )MR) obtained from Micromat data
(new F/MT instrument), using the following equations:
2
Circularity x 3.14 x 1.52
Hs (Standard fineness
Diameter (microns) 
or Final format (D) (microns) = 1.205 Hs
or
Circularit y × 1.52
4 x 3.14 x Hs
Perimeter (microns) 
or Final format (P) (microns) = 3.7853 Hs
Results of the current study suggested that
more attention should be focused on meaning and
measurements of the three values of biological
fineness (i.e.) diameter (D), perimeter (P) (microns)
and standard fineness (Hs) m/tex. which
can be derived from the data obtained from Micromat
instrument.