The gravimetric determinations of airborne particulate contamination has always required the use of P.V.C. membrane filters. Until now, the investigator had to purchase the filters separately from the air sampling cassette, proceed to weigh the filters, place them in cassettes, identify each cassette and record the identifying number and the tare weight of the filter contained in each cassette.

Well, now Omega Specialty Instruments has introduced pre weighed P.V.C. filters in 37mm cassettes, each cassette is individually marked with the weight of the filter it contains, and a lot number.

The weight is available in two different accuracies: 4 decimal and 5 decimal. All weighings are made on a Cahn Microbalance, Model C-30 to .001 mg and rounded to the next significant figure.

The pre weighed cassettes are handy for surveys prior to documenting trouble spots. Using pre weighed filters contravenes an OSHA directive that calls for both primary (tare) and secondary (after sampling) weighing to be performed on the same microbalance.

For complying with the above requirement and still having a reduction in one's workload, the investigator should consider using Match-Weigh™ Filters of P.V.C.

As an additional service, pre weighed cassettes can br furnished pre-banded and/or serially pre-numbered.

Specifications:

Filter                         :- Pure Homopolymer of PVC (PH-PVC)

Pore Size                  :- 5.0µ m, 0.8µ m

Cassette Size           :-  Clear polystyrene 37mm in 2pc or 3pc version

Support Pad Pure    :-  Cellulose fiber

Weighing Accuracy :-    0.000 X g    or     0.0000 X g

                                                   (4 decimal)                   (5 decimal)

QUALITY ASSURANCE

Each box of Pre-Weigh™ cassettes is accompanied with one of the following certificates, your assurance of quality: