NH3 Sampling Protocol (PDF 112 KB)

Ogawa & Co., USA, Inc. 1 NH3 Sampling Protocol Using The Ogawa Sampler* Ogawa & Company, USA, Inc. 1230 S. E. 7th Avenue, Pompano Beach, Florida 33060, USA Tel: (954) 781-6223 Fax: (954) 781-6224 email: dschaeff@ogawausa.com Ogawa & Co., Ltd 3-2-15, Nakamachi-dori, Chuo-ku, Kobe 650, Japan Tel: (798) 33-6485 Fax: (798) 36-4848 email: hirogawa@kh.rim.or.jp V3.98 Yokohama City Research Institute for Environmental Science 1-2-15, Takigashira, Isogo-ku, Yokohama, 235-0012 Japan TEL(045)752-2605 FAX(045)752-2609 E-mail kanken@city.yokohama.jp 2 Ogawa & Co., USA, Inc Notice Certain products mentioned in this User’s Guide may be trademarks. These products have been mentioned for identification purposes only. Version Number Edition Month / Year 1.0 September / 2005 Ogawa & Co., USA, Inc. 3 General Information 1. "Water", in all cases, shall mean water meeting ASTM Type I specifications. (Equal to Milli-Q by Millipore). Use Reagent grade chemicals for all applications. 2. "Wash", in all cases, shall mean cleaning thoroughly with water meeting ASTM Type I specifications. 3. All sampler components should be carefully washed and dried before each use. This is an important function, and special care should be taken to do this step carefully. 4. Washing, drying, assembly of sampler, and loading with the proper pre-coated filters should be done in a clean area, free of NH3 contamination. It is not necessary to use a glovebox. 5. When the point of research is outdoors, the sampler should be given protection from the sun and rainfall. Ogawa & Co., USA, Inc. has an opaque shelter and mounting bracket designed for that purpose. 6. Direct exposure of individuals can be easily measured by using the alligator clip to attach the sampler to clothing as close to the face as possible. 4 Ogawa & Co., USA, Inc Ogawa Sampler Assembly The sampler is comprised of 2 chambers. In each chamber of the sampler, the assembly stack-up is described below. Start at the innermost position with the pad and progress outwards to the diffuser end cap. 1 Solid Pad2 Pad Retaining Ring3 Stainless Screen4 Coated Collection Filter5 Stainless Screen6 Diffuser End Cap Ogawa & Co., USA, Inc. 5 Transport and Storage After assembly, the loaded sampler is placed into the re-sealable plastic bag. The bagged sampler is placed into the brown airtight container, provided, and taken to the exposure site. After exposure, the above procedure is again followed to safely seal the used sampler into the brown airtight vial. It is then taken to the laboratory for analysis. The sampler has the following lifetime associated with the various components Refrigerated Storage Method Frozen Storage Method Sealed in glass vial and aluminum pouch 90 days 1 year Resealed in vial, after opening 90 days Loaded sampler in bag placed in brown vial with lid 90 days Exposed loaded sampler, in bag placed in brown vial with lid 14 days Extracted solution in water, in sealed vial 90 days Table 1: Shelf life associated with Passive Sampler Components 6 Ogawa & Co., USA, Inc Application of the Sampler in an Outdoor Micro-Environment It is mandatory to protect the loaded sampler from moisture while it is being exposed. To accomplish this task, and still retain proper airflow to the device, it is necessary to use P/N PS-115 Opaque Shelter w/sampler bracket, which is shown on our price list as being for NO-NOx, NO2, and SO2. The PS-115 mounting bracket is attached to the site using several small screws or by passing a wire through two holes on each side of the bracket and then around the pole or post. The sampler easily clips on to the bracket and the cup slides over the bracket to protect the sampler. The PS-106 sampler bracket, once the sampler is clipped to it, easily slips over the shelter to hold the sampler in the correct position within the shelter. Ogawa & Co., USA, Inc. 7 NH3 Analytical Procedure using Ogawa Sampler 1. Preparing of the NH4? Standard Solution Pr imary Standard Solu tion (1000 ?g NH4?/ml) Take Out 10 ml 100 ml Flask By using a p ipette Dilu te 10 ml primary standard solu tion with pure water to make 100 ml secondary so lu tion . Secondary Standard Solu tion (10 ?g NH??/ml) Take Out 100 ml Flask By using a p ipette Dilu te 1 ml secondary standard solu tion with pure water to make 100 ml working standard solu tion . (0 .1 ?g NH??/ml) Dilu te 10 ml secondary standard solu tion with pure water to make 100 ml working standard solu tion . (1 .0 ?g NH4?/ml) Working Standard Solu tion of 0.1 ? 10 ?g NH??/ml 4. Analytical Procedure of NH3 Exposed Pads and Blank r Pads 25 ml Test Tube Pu t the exposed pad in to test tube. Add 8 ml water in to test tube. Extraction 8 Ogawa & Co., USA, Inc Af ter ex tracted 30 minutes , shake s lowly. Analyzed by IC 5. Calculation for NH3 Concentration Value for Value for Value for Exposed Pads Black Pads Standard Solution Calculate for Standard Curve Fundamental Data for Exposed Time, Temperature, Relative Humidity Calculation for the Collected Amounts of NH3 [Collected Amounts of NH3] = ([Exposed Pads]-[Blank Pads])*[Extract Quantity 8 ml] [Gradient of Standard Curve for NH3] Calculation of Concentration for NH3 NH? concentration = ?*[NH3 Collected Amounts]/[Exposed Time] NH3 Concentration : ppb NH3 Collected Amounts : ng Exposed Time : min Sampling Rate = 32.3 ml/min ? = 43.8 ppb?min/ng Determination Results