Asbestos Fiber Analysis

Asbestos Fiber Analysis

Walton and Beckett Graticule for Asbestos

Calibration factors are required for each of these graticules. See note below.

The Walton and Beckett graticule is used for counting fibrous dust (e.g. asbestos or glass fibers) and is particularly useful where the majority of fibers to be counted are shorter than 5 microns. The circle is divided into four by two diametrical lines scaled in units of 5 and 3 microns respectively. 3 and 5 microns are the critical measurements of fiber lengths and diameters used in fiber counting. Unlike the usual globes of other particle graticules, the Walton and Beckett have a series of shapes to compare objects with. These shapes have been designed for comparison with fibers, especially since they incorporate an aspect ratio of 3:1 or 5:1, essential for such analysis.

Important Note: The circle on these Walton & Beckett graticules must represent 100 microns at the stage and each one must be manufactured to suit the individual instrument.

Therefore, the following details should be provided with your order:

  1. Calibration factor, if known
  2. Objective magnification
  3. Eyepiece magnification
  4. Diameter of graticule disc required
  5. Microscope make and model
Pattern Description Dia Cat #
G22 Walton & Beckett for asbestos, 3:1 ratio.
Glass sandwich.
16 mm 68028-16
19 mm 68028-19
20.4 mm 68028-20.4
21 mm 68028-21
23 mm 68028-23
24.5 mm 68028-24.5
25 mm 68028-25
26 mm 68028-26
27 mm 68028-27
G24 Walton & Beckett for asbestos, 5:1 ratio.
Glass sandwich.
16 mm 68029-16
19 mm 68029-19
21 mm 68029-21
G25 Based on the G22, the G25 is produced by the Institute of Occupational Health (1996).
Glass sandwich.
16 mm 68030-16
19 mm 68030-19
21 mm 68030-21
Cat # Description Pack Price Quote Quantity
Cat #: 68028-16 Description: G22 Walton & Beckett Graticule, 16mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-19 Description: G22 Walton & Beckett Graticule, 19mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-20.4 Description: G22 Walton & Beckett Graticule, 20.4mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-21 Description: G22 Walton & Beckett Graticule, 21mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-23 Description: G22 Walton & Beckett Graticule, 23mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-24.5 Description: G22 Walton & Beckett Graticule, 24.5mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-25 Description: G22 Walton & Beckett Graticule, 25mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-26 Description: G22 Walton & Beckett Graticule, 26mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68028-27 Description: G22 Walton & Beckett Graticule, 27mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68029-16 Description: G24 Walton & Beckett Graticule, 16mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68029-19 Description: G24 Walton & Beckett Graticule, 19mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68029-21 Description: G24 Walton & Beckett Graticule, 21mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68030-16 Description: G25 Walton & Beckett Graticule, 16mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68030-19 Description: G25 Walton & Beckett Graticule, 19mm Pack: Each Price: $308.00 Add to Quote:
Cat #: 68030-21 Description: G25 Walton & Beckett Graticule, 21mm Pack: Each Price: $308.00 Add to Quote: