Section 3: Apparatus

3.1 Sampling Train
3.2 Sample Preparation and Recovery

The following equipment is required:

Nozzle: A button-hook type nozzle with a sharp, tapered leading edge. The nozzle is usually made of 316 stainless steel or Incoloy 825, but quartz or equivalent material may be used when high temperature or corrosive gases are encountered. The minimum inside diameter of the nozzle shall be 4.76 mm (3/16 inch).
Probe: A borosilicate or quartz glass liner, encased in a stainless steel tube with a heating and temperature indicating system capable of maintaining the exit gas temperature at 120 ± 14°C (248 ± 25°F), or at such a temperature necessary to prevent condensation. Where length or strength limitations preclude the use of a glass liner, a seamless tubing made from an inert material such as Teflon may be used. A water-cooled probe should be used when very hot gases which could damage the nozzle/probe assembly are encountered.
Pitot Tube: A calibrated S-type (Stausscheibe) pitot tube mounted on the probe assembly.
Stack Temperature Sensor: A thermocouple, or other suitable temperature sensor, mounted on the probe assembly, capable of measuring the stack temperature to within 1.5% of the minimum absolute stack temperature. When high temperature gases are encountered, appropriate shielding and aspiration should be provided for the thermocouple so that radiation effects are avoided.
Cyclone (Optional): A borosilicate miniature cyclone placed after the sampling probe and before the filter may be used to collect large particles. The cyclone prevents premature buildup of particulate matter on the filter medium and permits longer sampling periods. The cyclone is located inside the filter compartment and is kept at a temperature of 120 ± 14°C (248 ± 25°F).
Filter Holder: A borosilicate filter holder with an inert filter support. The filter support, which consists of a perforated disc, shall be constructed of Teflon to provide a seal against leakage at any point along the filter circumference. The filter holder is located inside the filter compartment and is maintained at a temperature of 120 ± 14°C (248 ± 25°F).
Filter: A high-efficiency glass or quartz fibre filter, which contains no organic binders and is capable of at least 99.95% efficiency for 0.3 μm dioctyl phthalate smoke particles as determined by ASTM Method D2986-71.
Filter Compartment Heating System: A heating system capable of maintaining the temperature in the filter holder compartment at 120 ± 14°C (248 ± 25°F), or at such a temperature necessary to prevent blinding of the filter. A thermocouple or other temperature sensor must be able to read the filter compartment temperature to within 3°C (5°F).
Organic Sampling Module: This unit consists of a gas condensing coil, a sorbent trap and a condensate knockout trap. The condenser must be able to condition the stack gas leaving the back-half of the filter holder at a temperature below 20°C (68°F). The sorbent trap shall be sized to contain 30-40 g of porous polymeric resin, Amberlite XAD-2. The sorbent trap should contain a glass well to accommodate a thermocouple to permit monitoring of the temperature of the gas sample entering the sorbent. The organic sampling module shall be oriented so that the condensate flows vertically, downward through the XAD-2 resin, into the condensate trap. The condensate trap shall be suitably sized and designed to prevent bubbling and carryover of condensate into the impingers.

A peristaltic or submersible pump shall be used to circulate the coolant through the XAD-2 trap and condenser. Ice water from the impinger bath may be used as the coolant.

All components of the organic module (condenser, XAD-2 trap and condensate trap) shall be fabricated of borosilicate glass. These components are not available commercially, but they may be custom fabricated from available laboratory glassware.

Impingers: Three Greenburg-Smith impingers are connected in series. The second and third impingers are modified by replacing the tips and impaction plates of the standard design with a 13 mm (0.5 inch) inside diameter glass tube extending to within 13 mm (0.5 inch) from the bottom of the impinger. The first impinger has the standard tip and impaction plate. The impingers are contained in an ice bath during sampling. The first impinger shall contain a known volume of ethylene glycol. The second shall remain empty and the third shall contain a known weight of silica gel.
Vacuum Pump: A leakproof vacuum pump capable of maintaining an isokinetic sampling rate while continuously withdrawing a portion of the stack gases through the samplingtrain is used. The pump intake vacuum is measured to within 13 mm mercury (Hg) (0.5 inch Hg) by a vacuum gauge which is attached to the vacuum line connecting the pump to the last impinger outlet. The sample flow rate is controlled with both coarse-and fine-flow control valves.
Dry Gas Meter: A calibrated dry gas meter with inlet and outlet temperature sensors, or one that is temperature-compensated. The sensors must be capable of measuring the temperatures to within 3°C (°F).
Orifice: A calibrated orifice connected to the outlet of the dry gas meter is required.
Differential Pressure Gauges: Differential pressure gauges such as an inclined manometer, or a device of equal sensitivity, which are capable of measuring the pitot tube velocity pressure and the pressure drop across the orifice to within 0.13 mm (0.005 inch) H₂O on the 0 to 25 mm (0 to 1 inch) H₂O scale, and readable to the nearest 1.3 mm (0.05 inch) H₂O for ΔP values greater than 25 mm H₂O. A more sensitive device shall be required when ΔP values are less than 1.3 mm H₂O (0.05 inch H₂O).

Probe Brush: A nylon bristle brush of a length and diameter suitable for cleaning the probe. The brushes shall be cleaned prior to field use and shall have stainless steel or Teflon extensions.
Wash Bottles: Teflon wash bottles are necessary to dispense the recovery solvents. Polyethylene wash bottles shall not be used as the organic solvents stored in the bottle may extract organic contaminants.
Sample Storage Containers: Wide-mouthed amber glass bottles to store the hexane and acetone rinse. The screw caps shall be lined with Teflon lid liners. Both the amber glass bottles and the Teflon lid liners shall be cleaned. The amber glass bottles shall be proofed prior to field use. Both 500-mL and 1000-mL capacity bottles are required.
Petri Dishes: Glass petri dishes to store and transport the filters. The glass petri dishes shall be cleaned before field use.
Teflon Lid Liners: Teflon sheet to line the inside of the screw caps. The lid liners shall be cleaned prior to field use.
Teflon Tape and Sleeves: Teflon tape is necessary to seal the circumference of the filter holder and the glass ball joints. Both 13-mm (1/2-inch) and 25-mm (1-inch) wide tape is required. The Teflon sleeves are used to seal the tapered impinger joints.
Glass Wool: Glass or quartz wool to plug the unfritted end of the sorbent trap. The wool shall be cleaned prior to field use.
Aluminum Foil: Aluminium foil to wrap the loaded filter and to cover the open ends of the train glassware. The foil shall be cleaned before use.
Miscellaneous: Miscellaneous glassware such as graduated cylinders, glass plugs and caps and funnels. This glassware shall be cleaned prior to field use. Tweezers (stainless steel or Teflon) and disposable plastic gloves are also required. Do not use latex gloves or gloves with powdered inside surfaces.

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Section 3: Apparatus

Page details

This historical page is being kept for research or referencepurposes and will not be updated.

This historical page is being kept for research or referencepurposes and will not be updated.

Section 3: Apparatus

Page details

This historical page is being kept for research or reference
purposes and will not be updated.

This historical page is being kept for research or reference
purposes and will not be updated.