FID Gas MeterDetector FID Gas MeterDetector Introduction Air

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FID Gas Meter/Detector

FID Gas Meter/Detector

FID Gas Meter/Detector Introduction Air monitoring data is useful for: * Assessing the health

FID Gas Meter/Detector Introduction Air monitoring data is useful for: * Assessing the health risks to the public and response workers. * Selecting personal protective equipment. * Delineating areas where protection is needed. * Determining actual or potential effects on the environment. * Selecting actions to mitigate the hazards safely and effectively.

FID Gas Meter/Detector To be useful air monitoring instruments must be: * Portable and

FID Gas Meter/Detector To be useful air monitoring instruments must be: * Portable and rugged. * Easy to operate. * Inherently safe. * Able to generate reliable and useful results.

Toxic Atmosphere Monitors Toxic atmosphere monitoring is done to: * identify airborne concentrations that

Toxic Atmosphere Monitors Toxic atmosphere monitoring is done to: * identify airborne concentrations that could pose a toxic risk to response workers and the public. * evaluate the need for and type of personal protective equipment. * set up work zones or areas where contaminants are or are not present.

FID Gas Meter/Detector n The response time, sensitivity, selectivity, accuracy and precision of an

FID Gas Meter/Detector n The response time, sensitivity, selectivity, accuracy and precision of an instrument are important in evaluating the reliability and usefulness of the data the instrument generates.

FID Gas Meter/Detector Limitations & Considerations Temperature n Oxygen Levels n Interfering Coumpounds u

FID Gas Meter/Detector Limitations & Considerations Temperature n Oxygen Levels n Interfering Coumpounds u Organic Lead u Sulfur compounds u Silicone u Acid Gases n

FID Gas Meter/Detector • One of the most widely used • Generally applicable detectors

FID Gas Meter/Detector • One of the most widely used • Generally applicable detectors • Easy to use but destructive of the sample.

FID Gas Meter/Detector 1. FIDs consist of a hydrogen/air flame and a collector plate

FID Gas Meter/Detector 1. FIDs consist of a hydrogen/air flame and a collector plate 2. effluent from column is mixed with hydrogen and air and then ignited electrically 3. most organic compounds produce ions and electrons that can conduct electricity through the flame 4. electrode above the flame collects the ions 5. number of ions hitting the collector is measured and a signal is generated

FID Gas Meter/Detector norganic molecules undergo a series of reactions including thermal fragmentation, chemi-ionization,

FID Gas Meter/Detector norganic molecules undergo a series of reactions including thermal fragmentation, chemi-ionization, ion molecule and free radical reactions to produce charged-species namount of ions produced is roughly proportional to the number of reduced carbon atoms present in the flame and hence the number of molecules nbecause the flame ionization detector responds to the number of carbon atoms entering the detector per unit of time, it is a mass-sensitive, rather than a concentration-sensitive device nthis detector has the advantage that changes in flow rate of the mobile phase has little effects on detector response

FID Gas Meter/Detector ncarbonyl, alcohol, halogen, and amine, yield fewer ions or none at

FID Gas Meter/Detector ncarbonyl, alcohol, halogen, and amine, yield fewer ions or none at all in a flame ndetector is insensitive toward noncombustible gases

References Cited http: //www. enviroequipment. com/products/fox_tva 1000. html http: //members. kr. inter. net/guesu/gs/e_detecti on/flame-ionization-detector.

References Cited http: //www. enviroequipment. com/products/fox_tva 1000. html http: //members. kr. inter. net/guesu/gs/e_detecti on/flame-ionization-detector. html Accessed 05/01/01 NIOSH Manual of Analytical Methods (NMAM®), 4 th ed. DHHS (NIOSH) Publication 94 -113 (August, 1994), Cassinelli, M. E. & O'Connor, P. F. (pfo 1@cdc. gov), Eds.

Bibliography Di. Nardi Salvatore R. (1998) The Occupational Environment-Its Evaluation and Control, AIHA, Fairfax,

Bibliography Di. Nardi Salvatore R. (1998) The Occupational Environment-Its Evaluation and Control, AIHA, Fairfax, Virginia n Goetsch David L. (1999) Occupational Safety and Health for Technologists, Engineers, and Managers, Prentice Hall, Upper Saddle River, New Jersey n