Monitoring continuous gas

Most industrial hygiene air monitors in the semiconductor industry are used for flammable and toxic gas leak detection (see Ch. 11, Toxic Gas Monitoring). However, some facilities are also using continuous monitoring systems to  

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Within the semiconductor industry a variety of continuous gas monitors are used (see Sec. 2.5 and Ch. 11, Toxic Gas Monitoring, for additional information). Historically, thesemonitors were primarily used to determine if a toxic gas leak had occurred, rather than actual measurements of breathing zone concentration of chemicals. Sample points for the monitors were located in exhausted enclosures as well as in potential release points in the clean room. 

The person in charge of the work reviews the hazards identified in the pre-job plan and states what safety precautions must be followed during the course of the work. These can include PPE, gas retesting, continuous gas monitoring, spark containment, and the use of fire extinguishers. These conditions are noted on the work permit. 

Continuous Emissions Monitoring. A key aspect of the new CAAA is the requirement that plants prove their continued compHance to new emissions limits by installing continuous emissions monitoring systems (CEMs). The CAAA imposes new requirements for monitoring NO, SO2, and CO2 levels in a plant s exhaust gas stream. Affected plants typically must gather data from stack monitoring systems, gas analyzers, and the plant s data acquisition system and provide the data in a format approved by the EPA and state regulators. CEM systems must be in place by November 1993 for boilers affected by Phase I of the CAAA, and byjanuary 1995 for plants impacted by Phase II. 

Applications Transportable FTIR analyzers have been used in monitoring applications such as continuous emissions monitoring, process gas analysis, and car exhaust and industrial air hygiene. 

Miller W.W., Yafuso M., Yan C., Hui H.K., Arick S., Performance of an in vivo, continuous blood-gas monitor with disposable probe, Clin. Chem. 1987 33 1538. 

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M. Ganter and A. Zollinger, Continuous intravascular blood gas monitoring development, current techniques, and clinical use of a commercial device. Bri. J. Anaesthesia 91, 397-407 (2003). 

M.A. Pakulla, D. Obal, and S.A. Loer, Continuous intra-arterial blood gas monitoring in rats. Lab. Animals 38, 133-137 (2004). 

The concentration of 222Rn in air was determined with a radon measurement detector. The detector allows realizing continuous radon monitoring. It consists of an electronic unit and a scintillation cell. The electronic unit contains power supply, amplifier, discriminator, timer, counter, and indicator. The scintillation cell contains the zinc sulfide scintillator, photomultiplier, preamplifier, high voltage power supply and chamber with a volume of 200 mL over the scintillator. This chamber is filled with the gas to be analyzed. The air is either pumped or diffuses into the scintillation cell. The scintillation count is processed by electronics, and radon concentrations for predetermined intervals are stored in the memory of the device. 

Automatic Continuous Air Monitoring System (ACAMS) This system can detect G agents, VX, or mustard agents at very low levels. It is an automatic gas chromatograph that first collects agent on a solid sorbent and then thermally desorbs the agents into a separation column for analysis. 

Conrad s Centralia plant has no pollution control equipment except for the outside flare for the excess gas. No continuous emissions monitoring systems are used. No local regulations apply to the facility, although an annual inspection is conducted on site by regulatory agencies. 

The Miniature automatic Continuous Agent Monitoring System (MiniCAMS ) utilizes an automated near-real-time gas chromatograph. An air sample is drawn through a preconcentrator loop filled with an... 

Continuous hemodynamic monitoring is essential during all phases of hypothermia. Cardiac monitoring is necessary because of the increased risk of arrhythmias. Cardiac output is decreased 5% for every 1°C of body temperature reduction. This is thought to be secondary to bradycardia, which has been shown to occur with hypothermia (3). A pulmonary artery catheter may be placed if there is any question of hemodynamic instability. Arterial catheters are used for continuous blood pressure measurement, as well as for access to arterial blood for blood gas and electrolyte analysis. 

The ventilated air and gaseous waste from the controlled area are released through the stack after dealing with high efficiency particulate air filters. There are two methods of continuously monitoring the concentration in exhaust gas. One is to measure the gas directly with a detector inserted into the stack or duct and the other is to measure a portion sampled from the exhaust air with a dust monitor or a gas monitor. 

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