For the purpose of preparing the fundamental data on air pollution in underground shopping center and also contributing to the health improvement of resident, the authors measured the level of SO2, NO2, TSP, CO, CO2 and also some related factors as air temperature, air movement, relative humidity and mean radiation temperature at inside and outside of underground shopping center in Pusan from January to February and from July to August 1994. The results were as follows: 1. The mean concentration of CO within the underground shopping center was 3.1+/-1.3ppm in winter and 2.1+/-0.9 ppm in summer. There was a negative correlation (p<0.01) between inner CO concentration and temperature in summer and no correlation between inner CO concentration and outer CO concentration in underground shopping center 2. The mean concentration of C02 within the underground shopping center was 876+/-353 ppm in winter and 757+/-125 ppm in summer. There was a negative correlation (P<0.01) between inner CO2 concentration and air movement in summer and positive correlation (p<0.05) between inner CO2 oncentration and outer CO2 concentration in underground shopping center. 3. The mean concentration SO2 within a underground shopping center was 0.036+/-0.019ppm in winter and 0.040+/-0.013ppm in summer. There was a positive correlation(p<0.01) between inner SO2 concentration and positive correlation between inner SO2 concentration and outer SO2 concentration in summer and winter in Underground shopping center. 4. The mean concentration of NO2 within a underground shopping center was 0.052+/-0.038ppm in winter and 0.042+/-0.016ppm in summer. There was a no correlation between inner NO2 concentration and thermal factors in summer and winter and low correlation between inner NO2 concentration in underground shopping center. 5. The mean concentration of TSP within a underground shopping center was 430+/-214 microgram/m3 in winter, 366+/-73 microgram/m3 in summer, and very in excess of the atmospheric environmental quality standards of Korea(150 microgram/m3). There was low correlation between inner TSP concentration and temperature in summer and high correlation between inner TSP concentration and outer TSP concentration in underground shopping center.
Air Movements ; Air Pollution* ; Busan* ; Humidity

At a brewery, the base plate-to-shell weld seam of a 90-m3 vertical cylindrical steel tank failed catastrophically. The 4 ton tank "took off" like a rocket leaving its contents behind, and landed on a van, crushing it. The top of the tank reached a height of 30 m. The internal overpressure responsible for the failure was an estimated 60 kPa. A rupture disc rated at < 50 kPa provided overpressure protection and thus prevented the tank from being covered by the European Pressure Equipment Directive. This safeguard failed and it was later discovered that the rupture disc had been installed upside down. The organizational root cause of this incident may be a fundamental lack of appreciation of the hazards of large volumes of low-pressure compressed air or gas. A contributing factor may be that the standard piping and instrumentation diagram (P&ID) symbol for a rupture disc may confuse and lead to incorrect installation. Compressed air systems are ubiquitous. The medium is not toxic or flammable. Such systems however, when operated at "slight overpressure" can store a great deal of energy and thus constitute a hazard that ought to be addressed by safety managers.
Compressed Air ; Rupture* ; Steel*

No abstract available.
Compressed Air* ; Mouth* ; Rupture*

For the determination of absorbed dose to water from a linear accelerator photon beams, it needs a exposure calibration factor Nx or air kerma calibration factor Nk of air ionization chamber. We used the exposure calibration factor Nx to find the absorbed dose calibration factors of water in a reference source through the TG-21 and TRS-277 protocol. TG-21 used for determine the absorbed dose in accuracy, but it required complex calculations including the chamber dependent factors. The authors obtained the absorbed dose calibration factor NdwCo-60 for reduce the complex calculations with unknown Ndw only with Nx or Nk calibration factor in a TM31010 (S/N 1055, 1057) ionization chambers. The results showed the uncertainty of calculated Ndw of IC-15 which was known the Nx and Ndw is within -0.6% in TG-21, but 1.0% in TRS-277. and TM31010 was compared the Ndw of SSDL to that of PSDL as shown the 0.4%, -2.8% uncertainty, respectively. The authors experimented with good agreement the calculated Ndw is reliable for cross check the discrepancy of the calibration factor with unknown that of TM31010 and IC-15 chamber.
Air Ionization ; Calibration ; Particle Accelerators ; Uncertainty ; Water

PURPOSE: The authors experienced a case of orbital emphysema causing eye movement disorder following conjunctival tear without any orbital wall fractures after exposure to compressed air. CASE SUMMARY: A 28-year-old man's left periorbital area was injured while working with compressed air. There was marked lid swelling on the left side with palpable crepitus. The patient had an exotropia and hypertropia of the left eye. In addition, the extraocular movement of the left eye was restricted on upgaze without nausea and vomiting. On slit-lamp examination, conjunctival partial laceration and subconjunctival air bubbles adjacent to the conjunctival laceration could be seen. Orbital computed tomography showed air in the periorbital and retrobulbar region of the left eye and no evidence of orbital fracture. On examination 4 days after the primary repair of the conjunctival laceration, the patient completely recovered without any complication. CONCLUSIONS: Orbital emphysema following a conjunctival laceration caused by compressed air without any orbital wall fractures can cause restriction of eye movement.
Adult ; Compressed Air* ; Emphysema* ; Exotropia ; Eye Movements* ; Humans ; Lacerations ; Nausea ; Ocular Motility Disorders ; Orbit* ; Orbital Fractures* ; Strabismus ; Vomiting

No abstract available.
Compressed Air* ; Explosions* ; Orbit* ; Orbital Cellulitis*

This study is to keep the accuracy and stability of the output dose evaluations for linear accelerator photon beams by using the air ionization chambers (TM31010, 0.125 cc, PTW) through the Task Group 51 protocol. The absorbed dose to water calibration factor NdwCo-60 was delivered from the air kerma calibration factor Nk which was provided from manufacture through SSDL calibration for determination of output factor. The ionization chamber of TM31010 series was reviewed the calibration factor and other parameters for reduce the uncertainty within +/-2% discrepancy and we found the supplied NdwCo-60 which was derived from Nk has shown a -2.8% uncertainty compare to that of PSDL. The authors provided the program to perform the output dosimetry with TG-51 protocol as it is composed same screen of TG-51 worksheets. The evaluated dose by determination of output factor delivered to postal TLD block for comparison the output dose to that of MDACC (RPC) in postal monitoring program. The results have shown the 1.001+/-0.013 for 6 MV and 0.997+/-0.012 discrepancy for 15 MV X rays for 5 years followed. This study shows the evaluated outputs for linear accelerate photon beams are very close to that of international output monitor with small discrepancy of +/-1.3% with high reliability and showing the gradually stability after 2010.
Air Ionization ; Calibration ; Organothiophosphorus Compounds ; Particle Accelerators ; Phenylpropionates ; Uncertainty ; Water

Colon barotrauma can be mostly caused by elevated intraluminal pressure. Air insufflation during colonoscopy procedure is the most common cause of iatrogenic colon barotrauma. Cat scratch colon can usually be seen in the mild type of colon barotrauma, and colon perforation can be seen in the severe type. We presently report a case of non-iatrogenic colon barotrauma caused by industrial compressed air. Multiple linear mucosal ulcers were noted in the recto-sigmoid colon, but the colon was not perforated. The patient was discharged without any further complications after conservative treatments.
Animals ; Barotrauma ; Cats ; Colon ; Colonoscopy ; Compressed Air ; Humans ; Insufflation ; Ulcer

An air-compressor system takes atmospheric air, and filters, pressurises and dries it, before delivering it to the pipeline as a medical air. Because the air supplied by the air compressor may be used to wentilate patients or to drive surgical tools, its quality and purity must be carefully controlled. Atmospheric air contains a variable amount of water vapour but always more than is specified for medical air. Water vapour must be removed from medical air since it can damage surgical tools and some ventilators and can condense in low-lying parts of the pipeline system. Reeently we have had experience of pneumothorax by pulmonary barotrauma associated with obstruction of the ventilator exhalational valve. As a result of investigating the possible causes, we concluded the cause as high moisture content in the compressed air due to the malfunctioning air drier and filters. Therefore we submit this case report along with discussion and literature reviews.
Barotrauma ; Compressed Air* ; Humans ; Pneumothorax ; Ventilators, Mechanical* ; Water

The natural ventilation widely used in greenhouses has advantages of saving energy and reducing expense. In order to provide information for climate control of greenhouse, a model was developed to predict the variation of air temperature in the naturally ventilated greenhouse equipped with insect-proof screen. Roof ventilation and combined roof and sidewall ventilation were considered in the model. This model was validated against the results of experiments conducted in the greenhouse when the wind was parallel to the gutters. The model parameters were determined by the least squares method. In the used model, effects of wind speed and window opening height on the air temperature variation were analyzed. Comparison between two types of ventilation showed that there existed a necessary ventilation rate which results in air temperature decrease in natural ventilation under special climatic conditions. In our experiments when wind speed was less than 3.2 ms(-1), wind had a more gradual effect on greenhouse temperature for roof ventilation, compared with combined roof and sidewall ventilation, which had greater air temperature decrease than roof ventilation only.
Air Conditioning ; instrumentation ; methods ; Air Movements ; Computer Simulation ; Computer-Aided Design ; Equipment Design ; Equipment Failure Analysis ; methods ; Insect Control ; instrumentation ; methods ; Models, Theoretical ; Plant Development ; Plastics ; Rheology ; instrumentation ; methods ; Temperature ; Wind