COLIFORM FILTERS. All filters listed on this page are white with black grids, 47 mm diameter, sterile.

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1 COLIFORM FILTERS Which filters do I use for Fecal coliforms, and which do I use for Total coliforms? According to the 22 nd edition of Standard Methods, Procedure 9222B (Total Coliform MF-Procedure) and Procedure 9222D (Fecal Coliform MF-Procedure): Use only those membrane filters that have been found through adequate quality control testing and certification by the manufacturer, to exhibit full retention of the organisms to be cultivated (emphasis added by us). All of the manufacturers for the grid filters listed in this catalog said they have written statements that certify their filters conform to the requirements of Standard Methods. However, the certification does not mention any specific organisms. So apparently, they do not certify their filters specifically for fecal or total coliforms. Numerous telephone calls to each of them have not resulted in clarification of this question. Millipore spokesmen stated that their type HCWG (pore size=0.7 µm, NCL# FM-150) is recommended for fecal coliforms, and that their type HAWG (pore size=0.45 µm, NCL# FM-151) is recommended for total coliforms. This runs contrary to the conventional wisdom of using the 0.45 µm pore size for fecal coliforms, but Millipore has confirmed this on several occasions. We do not have this in writing. The other manufacturers have informed us verbally that their grid filters are acceptable for both fecal and total coliforms, but will not state this in writing. All filters listed on this page are white with black grids, 47 mm diameter, sterile. Following is a list of grid filters which we stock. The main differences are in packaging, and whether pads are included. GRID FILTERS ONLY (NO PADS) Brand Manufacturer # Pore Size Description NCL # Price Pall µm FG-680B /pk of 200 NCL FG µm FG /pk of 200 NCL FG µm FG-690B /cs of 1000 Millipore HCWG047S µm FM /pk of 150 Individually wrapped, Millipore HCWG047S µm FM-150B /cs of 600 sterile Millipore HAWG047S µm FM /pk of 150 Millipore HAWG047S µm FM-151B /cs of 600 Advantec A045H047A 0.45 µm FM-454A 46.25/pk of 100 Advantec A045H047W 0.45 µm FM-454B /cs of 1000 GRID FILTERS WITH PADS Brand Manufacturer # Pore Size Description NCL # Price Whatman µm 100 individual bags, each containing one filter & one pad FW /pk of 100

2 Whatman GLASS FIBER FILTERS WHATMAN GRADE 934-AH GLASS FIBER FILTERS Grade 934-AH is approved by Standard Methods and will work for both Total Suspended Solids and Volatile Solids. Retention size: 1.5 microns. Packs of 100 circles. Diameter (cm) NCL # Price/pk 2.1 F F F F F F F F F F F F NCL GRADE 934-AH GLASS FIBER FILTERS 934-AH is a registered trademark of Whatman, Inc. The following Glass Fiber Filters are approved by Standard Methods and will work for both Total Suspended Solids and Volatile Solids. Retention size: 1.5 microns. Packs of 100 circles. 2.1 FN FN FN FN FN FN FN FN FN FN FN FN FN

3 GLASS FIBER FILTERS PRE-WASHED, PRE-WEIGHED FILTERS Whatman 934-AH, one of the most widely used filters for Total Suspended Solids analysis, is now available in a time-saving, Ready-To-Use (RTU) format: pre-washed and pre-weighed. Each RTU filter is packaged within an aluminum pan with the filter weight clearly printed on a heat resistant label. The 934-AH RTU meets the requirements under the latest edition of Standard Methods 2540D. 100 per pack. Each pre-treated filter comes in an aluminum pan with the filter weight clearly noted. First, place the 934-AH RTU on the funnel of the vacuum filtration apparatus and seal the filter to the funnel by wetting with a small amount of water. Then, filter your sample. Finally, wash the filter with three aliquots of 10 ml reagent grade water. Remove the filter, return it to the aluminum weigh pan and dry it to constant weight at 103 C to 105 C. To obtain the weight of total suspended solids, subtract the weight of the filter indicated on the pan label from the final weight RTU RTU RTU Order Toll Free

4 GLASS FIBER FILTERS The following Glass Fiber Filters are approved by Standard Methods and will work for Total Suspended Solids. NCL GRADE A-E GLASS MICROFIBER FILTERS Save money on your Grade A-E glass fiber filters by buying NCL brand instead of the other guy s. Guaranteed to be absolutely the same in particle retention, size, and performance. These filters meet the requirements for TSS testing as defined in Standard Methods. Retention size: 1.5 microns; 100 circles/pack. 2.1 AE AE AE AE AE AE AE AE AE AE AE AE AE PREWASHED FILTERS Many of you have requested these. As you know Standard Methods requires you to wash and dry TSS filters until they are of constant weight. This takes time and time is money. Prewashed filters are vacuum rinsed with 3 aliquots of deionized water. This step removes any loose fibers which could affect the filters constant weight. The filters are then dried at 105 C, cooled and desiccated for 24 hours. For those of you willing to spend the extra money, we offer these as follows. All are grade 934-AH. Retention size: 1.5 microns; packs of PWF PWF MILLIPORE GLASS FIBER FILTERS AP Glass fiber filters without binder. Retains structural integrity without weight loss when ignited at 550 C. 47 mm diameter. Packs of 500. FM /pk

5 GLASS FIBER FILTERS, FILTER PAPER The following Glass Fiber Filters are not mentioned by Standard Methods. OTHER WHATMAN GLASS FIBER FILTERS Listed below are the most popular sizes and grades. Please call if you don t see what you need. Diameter (cm) Type NCL # Price/pk V FF FF / Grade 3 FW / GF/A F / GF/A F / GF/A F / GF/A F / GF/A F / GF/A F / GF/B F / GF/B F / GF/B F / GF/B F /25 Diameter (cm) Type NCL # Price/pk 2.4 GF/C F / GF/C F / GF/C F / GF/C F / GF/C F / GF/D F / GF/D F / GF/D F / GF/D F / GF/D F / GF/D F /25 QUANTITATIVE FILTER PAPER MFS quantitative alpha cotton cellulose, acid washed, rinsed with ultrapure water to neutralize. Ash content 0.01% for fine particulates (<5 µm) FM-5C / FM-5C /100 Order Toll Free

6 WHATMAN #1: Qualitative, medium to fast speed. Retention size: 11 microns. 7.0 FW FW FW FW FW FW FW WHATMAN #2: Qualitative, medium speed. Retention size: 8 microns. 7.0 FW FW FW FW FW FW WHATMAN #4: Qualitative, fast speed. Retention size: 25 microns. 7.0 FW FW FW FW FW FW WHATMAN #5: Slow speed. Retention size: 2.5 microns. 7.0 FW FW FW FW FW FILTER PAPER WHATMAN #40: Ashless, medium speed. Retention size: 8 microns. 7.0 FW FW FW FW FW FW FW WHATMAN #41: Ashless, fast speed. Retention size: 25 microns. 7.0 FW FW FW FW FW WHATMAN #42: Ashless, slow speed. Retention size: 2.5 microns. 7.0 FW FW FW FW FW WHATMAN #541: Hardened, ashless, fast speed. Retention size: 25 microns. 7.0 FW FW FW FW FW WHATMAN GRADE 1PS PHASE SEPARATION FILTER PAPER For filtering water-solvent extractions, such as in the Oil & Grease procedure FW-1PS FW-1PS FW-1PS

7 FILTER DISPENSER, FILTER FUNNELS EZ-PAK DISPENSER AND MEMBRANES Dispense sterile membranes immediately with contamination-free and hands-free convenience. The EZ-Pak System revolutionized filter handling by combining the benefits of ready-to-use, sterile, individually-packed membranes with a unique dispenser. By simply depressing the dispenser s lever, the sterile membrane is unwrapped from its package for easy access. EZ /ea EZ-PAK GRIDDED MEMBRANE FILTERS MILLIPORE #EZHAWG mm diameter, 0.45 µm pore size, 600 filters per pack. EZ /pk DISPOSABLE FILTER FUNNELS WITH RECEIVER BASE Sterile, individually wrapped, 150 ml graduated filter funnel with receiver. Includes 47 mm membrane filter. After filtering the sample, upper section twists off for easy removal of membrane filter. For use in coliform determinations where autoclaving is not an option. Pore Size Membrane NCL # Price/cs 0.2 µm Plain FN / µm Gridded FN /72 DISPOSABLE FILTER FUNNELS Sterile, individually wrapped graduated funnel with 47 mm, 0.45 µm, gridded membrane filter. Each case includes 50 funnels and 6 funnel adapters (for use with NCL# R-777, rubber stopper). After filtering the sample, upper section twists off for easy removal of membrane filter. Funnel Size NCL # Price/cs 100 ml FN-145A ml FN-145B Order Toll Free

8 FILTER FUNNELS MAGNETIC FILTER FUNNEL Unbreakable polysulfone 300 ml funnel body accommodates 47 mm (4.7 cm) filters. Comes with rubber stopper to fit 1000 or 2000 ml suction flasks, or can be used with a filtration manifold. FG /ea Replacement screen for above KIMBLE GLASS FILTER FUNNEL ASSEMBLY Heavy duty glass microfiltration assemblies. Available in two filter sizes: 47 mm and 90 mm (for larger volumes). For vacuum filtrations. Each assembly consists of a graduated glass funnel, fritted glass support base, anodized aluminum clamp, and silicone stopper. (see picture of assembled product and breakdown showing components A through D) Complete assembly for 47 mm filters. Funnel size: 300 ml FK /ea FG-710C 30.00/ea Complete assembly for 90 mm filters. Funnel size: 1000 ml FK /ea A C B D REPLACEMENT PARTS FOR KIMBLE 300 ML FILTER FUNNEL ASSEMBLY Description NCL # Price/ea glass funnel, 47 mm, 300 ml FK-937A glass support base FK-937B clamp FK-937C silicone stopper with hole FK-937D REPLACEMENT PARTS FOR KIMBLE 1000 ML FILTER FUNNEL ASSEMBLY Description NCL # Price/ea glass funnel, 90 mm, 1000 ml FK-953A glass support base FK-953B clamp FK-953C silicone stopper with hole FK-953D 19.90

9 FILTER FUNNELS MFS GLASS FILTER FUNNEL ASSEMBLY Supplied with stainless steel screen support base, 300 ml graduated funnel, anodized aluminum clamp, and #8 silicone stopper. FS /ea MFS POLYSULFONE FILTER FUNNELS 300 ml graduated polysulfone funnel with recessed filter support to provide sufficient clearance so it will not twist or tear membrane filter. Comes with #8 stopper to fit 1000 ml suction flasks or MFS vacuum manifold. For use with 47 mm filters. Funnel top locks onto base with 1 /4 turn. Probably not as nice as the magnetic version, but a lot cheaper! FS /ea Order Toll Free