EPA Source Testing
High Temperature Capacity to 900 F
Differential Pressures to 100 in. H2O
Binderless fiberglass thimbles have become the media of choice for virtually all particulate stack sampling applications. Their popularity has been engendered by their high collection efficiency, large containment capacity and strength. Their slim profile make them ideally suited, but not limited to, stack sampling applications.
Exposure to temperatures of up to 900 F does not result in any significant weight loss. Differential pressures to 100 inches of water at 1 cfm will not cause rupture under dry conditions. All thimbles are manufactured to the same high standards as flat fiberglass paper and exceed 99.98% retention of 0.3mm DOP particles. For temperatures above 900 F, the 30 x 100 alundum should be utilized.
All fiberglass thimbles comply with EPA Methods 16 and 17*.
As the fabrication of fiberglass thimbles represents something of an art, the products of various manufacturers have a distinct character. Users have shown preference for one maker or another even though dimensional and engineering specifications are identical.
* Federal Register, Vol. 43, No. 37, Thursday, February
Literature Reference: "Particle Sizing in Industrial
Hygiene", by L. Silverman, C.E. Billings, and M.W. First, Academic Press Inc.,