Grade GF/A: 1.6 µm
Offers fine particle retention and high flow rate, as well as good loading capacity. Used for high-efficiency general purpose laboratory filtration, including water pollution monitoring of effluents, for filtration of water, algae and bacteria cultures, foodstuff analyses, protein filtration and radioimmunoassay of weak ß emitters. Recommended for gravimetric determination of airborne particulates, stack sampling and absorption methods of air pollution monitoring.
This filter is also available in the FilterCup and Disposable Filter Funnel formats.
Grade GF/B: 1.0 µm
Three times thicker than GF/A with higher wet strength and significantly increased loading capacity. Combines fine particle retention with good flow rate. Particularly useful where liquid clarification or solids quantification is required for heavily loaded fine particulate suspensions. Can be used as a finely retentive membrane prefilter. Used in LSC techniques where high loading capacity is required.
Grade GF/C: 1.2 µm
Combines fine particle retention with good flow rate. The standard filter in many parts of the world for the collection of suspended solids in potable water and natural and industrial wastes.
Fast and efficient clarification of aqueous liquids containing low to medium levels of fine particulates. Widely used for cell harvesting, liquid scintillation counting and binding assays where more loading capacity is required.
This filter is available in the FilterCup format.
Grade GF/D: 2.7 µm
Considerably faster in flow rate and overall filtration speed than cellulose filter papers of similar particle retention. The filter is thick and consequently exhibits a high loading capacity. Designed as a membrane prefilter and available in sizes to fit most holders. GF/D will provide good protection for finely retentive membranes. Can be used in combination with GF/B to provide very efficient graded prefilter protection for membranes.
Grade GF/F: 0.7 µm
This high-efficiency filter will retain fine particles down to 0.7 µm. Unlike membrane filters with a comparable retention value, it has a very rapid flow rate and an extremely high loading capacity.
Because of the tight specification of 0.6 µm - 0.8 µm particle retention and pure borosilicate glass structure, GF/F is the material upon which the EPA Method TCLP 1311 for Toxicity Characteristic Leaching Procedure was developed. It remains today the filter of choice.
Recommended for DNA binding and purification. Very effective in filtering finely precipitated proteins, GF/F can be used in conjunction with GF/D as a prefilter for the successful clarification of extremely ‘difficult’ biochemical solutions and fluids, and nucleic acids.
This filter is available in the FilterCup and Disposable Filter Funnel format.
Grade 934-AH: 1.5 µm
The fine particle retention of this popular grade is superior for its high retention efficiency at high flow rates and its high loading capacity. This is a smooth surface, high-retention borosilicate glass microfiber filter which withstands temperatures over 500°C. Used for determining total suspended solids in water, removal of turbidity, and filtration of bacterial cultures. Grade 934-AH is used for a wide range of laboratory applications. It is recommended for water pollution monitoring, cell harvesting, liquid scintillation counting, and air pollution monitoring.
Quartz Filter – Grade QM-A: 2.2 µm
High-purity quartz (SiO2) microfiber filters are used for air sampling in acidic gases, stacks, flues and aerosols, particularly at high temperatures up to 500°C and in PM-10 testing. Due to the low level of alkaline earth metals, ‘artifact’ products of sulfates and nitrates (from SO2 and NO2) are virtually eliminated. QM-A, sequentially numbered according to EPA standards, is suitable for most applications. Please refer to the Air Sampling Filter/Quartz Filters section for ordering information.
Grade EPM 2000: 2.0 µm
EPM 2000 has been developed especially for use in high volume air sampling equipment that collects atmospheric particulates and aerosols. It is manufactured from 100% pure borosilicate glass of special purity enabling detailed chemical analysis of trace pollutants to take place with the minimum of interference or background.  See Air Sampling Filter/Quartz Filters section for ordering details.
Grade GMF 150: 1 µm or 2 µm
The Whatman GMF 150 is a multilayer glass microfiber filter with a coarse top layer (10 µm) and meshed with a finer layer of 1 µm or 2 µm. Manufactured from 100% borosilicate glass microfiber, the filter is binder free. It is an excellent prefilter for higher particulate loading capacity with faster flow rates. See GMF 150 section for ordering information.


Typical Properties - Binder-Free Glass Microfiber Grades

Grade Description Particle
in liquid (µm)
herzberg (s)
Air flow 
GF/A Fast, high loading 1.6* 62 4.3 260 53
GF/B Medium to fast, very high loading 1.0* 195 12 675 143
GF/C Medium to fast, high loading 1.2* 100 6.7 260 53
GF/D Fast, very high loading 2.7 41 2.2 675 121
GF/F Medium, high loading 0.7* 325 19 420 75
934-AH Fast, high loading 1.5* 47 3.7 435 64
QM-A Quartz 2.2* - 6.4 450 85
EPM 2000 Used in PM-10 air monitoring 2.0* - 4.7 450 85
GMF150 - 1 µm Multilayer 1.2* - 3.1 730 139
GMF150 - 2 µm Multilayer 2.4* - 1.5 750 149

*Particle retention rating at 98% efficiency

Ordering Information - Glass Microfiber Binder Free

Catalog Number Description
Grade GF/A
1820-8013 Grade GF/A circles, 13 mm, 100/pk
1820-021 Grade GF/A circles, 21 mm, 100/pk
1820-024 Grade GF/A circles, 24 mm, 100/pk
1820-025 Grade GF/A circles, 25 mm, 100/pk
1820-030 Grade GF/A circles, 30 mm, 100/pk
1820-037 Grade GF/A circles, 37 mm, 100/pk
1820-042 Grade GF/A circles, 42.5 mm, 100/pk
1820-047 Grade GF/A circles, 47 mm, 100/pk
1820-050 Grade GF/A circles, 50 mm, 100/pk
1820-055 Grade GF/A circles, 55 mm, 100/pk
1820-060 Grade GF/A circles, 60 mm, 100/pk
1820-061 Grade GF/A circles, 60 mm with reinforced rim, 50/pk
1820-070 Grade GF/A circles, 70 mm, 100/pk
1820-6537 Grade GF/A circles, 81 mm, 100pk
1820-090 Grade GF/A circles, 90 mm, 100/pk
1820-110 Grade GF/A circles, 110 mm, 100/pk
1820-125 Grade GF/A circles, 125 mm, 100/pk
1820-150 Grade GF/A circles, 150 mm, 100/pk
1820-240 Grade GF/A circles, 240 mm, 100/pk
1820-866 Grade GF/A sheets, 8 x 10 inches, 100/pk
1820-915 Grade GF/A sheets, 460 x 570 mm, 25/pk
1600-820 Grade GF/A FilterCup, (requires FilterCup stem, catalog number 1600-900), 25/pk
1922-1820 Disposable Filter Funnel 25 ml, GF/A, 50/pk
Grade GF/B
1821-019 Grade GF/B circles, 19.1 mm, 50/pk
1821-021 Grade GF/B circles, 21 mm, 100/pk
1821-024 Grade GF/B circles, 24 mm, 100/pk
1821-025 Grade GF/B circles, 25 mm, 100/pk
1821-037 Grade GF/B circles, 37 mm, 100/pk
1821-042 Grade GF/B circles, 42.5 mm, 100/pk
1821-047 Grade GF/B circles, 47 mm, 100/pk
1821-055 Grade GF/B circles, 55 mm, 100/pk
1821-070 Grade GF/B circles, 70 mm, 100/pk
1821-090 Grade GF/B circles, 90 mm, 25/pk
1821-110 Grade GF/B circles, 110 mm, 25/pk
1821-125 Grade GF/B circles, 125 mm, 25/pk
1821-150 Grade GF/B circles, 150 mm, 25/pk
1821-185 Grade GF/B circles, 185 mm, 25/pk
1821-293 Grade GF/B circles, 293 mm, 25/pk
1821-914 Grade GF/B sheets, 460 x 570 mm, 5/pk
1821-915 Grade GF/B sheets, 460 x 570 mm, 25/pk
Grade GF/C
1822-021 Grade GF/C circles, 21 mm, 100/pk
1822-024 Grade GF/C circles, 24 mm, 100/pk
1822-025 Grade GF/C circles, 25 mm, 100/pk
1822-6580 Grade GF/C circles, 25 mm, 400/pk
1822-037 Grade GF/C circles, 37 mm, 100/pk
1822-042 Grade GF/C circles, 42.5 mm, 100/pk
1822-047 Grade GF/C circles, 47 mm, 100/pk
1822-050 Grade GF/C circles, 50 mm, 100/pk
1822-055 Grade GF/C circles, 55 mm, 100/pk
1822-070 Grade GF/C circles, 70 mm, 100/pk
1822-090 Grade GF/C circles, 90 mm, 100/pk
1822-100 Grade GF/C circles, 100 mm, 100/pk
1822-9916 Grade GF/C circles, 100 mm Individually bagged, 100/pk
1822-110 Grade GF/C circles, 110 mm, 100/pk
1822-125 Grade GF/C circles, 125 mm, 100/pk
1822-142 Grade GF/C circles, 142 mm, 100/pk
1822-150 Grade GF/C circles, 150 mm, 100/pk
1822-849 Grade GF/C Sheets, 102 x 254 mm, 50/pk
1822-866 Grade GF/C sheets, 8 x 10 inch, 100/pk
1822-914 Grade GF/C sheets, 460 x 570 mm, 5/pk
1822-915 Grade GF/C sheets, 460 x 570 mm, 25/pk
1600-822 Grade GF/C FilterCup, (requires FilterCup stem, catalog number 1600-900), 25/pk
1922-1822 Disposable Filter Funnel 25 ml, GF/C, 50/pk
Grade GF/D
1823-007 Grade GF/D circles, 7 mm, 100/pk
1823-010 Grade GF/D circles, 10 mm, 100/pk
1823-021 Grade GF/D circles, 21 mm, 100/pk
1823-024 Grade GF/D circles, 24 mm, 100/pk
1823-025 Grade GF/D circles, 25 mm, 100/pk
1823-035 Grade GF/D circles, 35 mm, 100/pk
1823-042 Grade GF/D circles, 42.5 mm, 100/pk
1823-047 Grade GF/D circles, 47 mm, 100/pk
1823-055 Grade GF/D circles, 55 mm, 100/pk
1823-070 Grade GF/D circles, 70 mm, 100/pk
1823-090 Grade GF/D circles, 90 mm, 25/pk
1823-110 Grade GF/D circles, 110 mm, 25/pk
1823-125 Grade GF/D circles, 125 mm, 25/pk
1823-142 Grade GF/D circles, 142 mm, 25/pk
1823-150 Grade GF/D circles, 150 mm, 25/pk
1823-257 Grade GF/D circles, 257 mm, 25/pk
1823-915 Grade GF/D sheets, 460 x 570 mm, 25/pk
Grade GF/F
1825-0134 Grade GF/F circles, 13 mm, 400/pk
1825-021 Grade GF/F circles, 21 mm, 100/pk
1825-024 Grade GF/F circles, 24 mm, 100/pk
1825-025 Grade GF/F circles, 25 mm, 100/pk
1825-037 Grade GF/F circles, 37 mm, 100/pk
1825-042 Grade GF/F circles, 42.5 mm, 100/pk
1825-047 Grade GF/F circles, 47 mm, 100/pk
1825-055 Grade GF/F circles, 55 mm, 100/pk
1825-070 Grade GF/F circles, 70 mm, 100/pk
1825-090 Grade GF/F circles, 90 mm, 25/pk
1825-110 Grade GF/F circles, 110 mm, 25/pk
1825-125 Grade GF/F circles, 125 mm, 25/pk
1825-142 Grade GF/F circles, 142 mm, 25/pk
1825-150 Grade GF/F circles, 150 mm, 25/pk
1825-257 Grade GF/F circles, 257 mm, 25/pk
1825-293 Grade GF/F circles, 293 mm, 25/pk
1825-915 Grade GF/F sheets, 460 x 570 mm, 25/pk
1600-825 Grade GF/F FilterCup, (requires FilterCup stem, catalog number 1600-900), 25/pk
Grade 934-AH
1827-021 Grade 934-AH circles, 21 mm, 100//pk
1827-024 Grade 934-AH circles, 24 mm, 100/pk
1827-025 Grade 934-AH circles, 25 mm, 100/pk
1827-027 Grade 934-AH circles, 27 mm, 100/pk
1827-028 Grade 934-AH circles, 28 mm, 100/pk
1827-030 Grade 934-AH circles, 30 mm, 100/pk
1827-032 Grade 934-AH circles, 32 mm, 100/pk
1827-035 Grade 934-AH circles, 35 mm, 100/pk
1827-037 Grade 934-AH circles, 37 mm, 100/pk
1827-042 Grade 934-AH circles, 42.5 mm, 100/pk
1827-047 Grade 934-AH circles, 47 mm, 100/pk
1827-055 Grade 934-AH circles, 55 mm, 100/pk
1827-070 Grade 934-AH circles, 70 mm, 100/pk
1827-132 Grade 934-AH circles, 81 mm, 100/pk
1827-082 Grade 934-AH circles, 82 mm, 100/pk
1827-085 Grade 934-AH circles, 85 mm, 100/pk
1827-090 Grade 934-AH circles, 90 mm, 100/pk
1827-105 Grade 934-AH circles, 105 mm, 100/pk
1827-110 Grade 934-AH circles, 110 mm, 100/pk
1827-125 Grade 934-AH circles, 125 mm, 100/pk
1827-150 Grade 934-AH circles, 150 mm, 100/pk
1827-185 Grade 934-AH circles, 185 mm, 100/pk
1827-240 Grade 934-AH circles, 240 mm, 100/pk
1827-320 Grade 934-AH circles, 320 mm, 100/pk
1827-808 Grade 934-AH sheets, 2 x 12 inches, 100/pk
1827-866 Grade 934-AH sheets, 8 x 10 inches, 100/pk
1827-889 Grade 934-AH sheets, 12 x 15 inches, 100/pk
1827-957 Grade 934-AH sheets, 19 x 28 inches, 100/pk
FilterCup Stem
1600-900 FilterCup stem, 1/pk