Objective: To explore the occupational hazards caused by three kinds of welding operations, and to provide data support for individual protection. Methods: In October 2020, the welding fumes, metal elements and welding arc generated by three welding operations of argon gas shielded welding (JS80 welding wire) , manual welding (ZS60A welding rod) and carbon dioxide shielded welding (907A flux cored wire) were collected and measured in the welding laboratory. The samples were analyze and compare in the laboratory, and the differences of the occupational hazard factors of the three welding operations were judged. Results: The concentration of welding fume produced by carbon dioxide shielded welding, manual welding (ZS60A electrode) , and argon gas shielded welding (JS80 welding wires) were 6.80 mg/m(3), 6.17 mg/m(3), and 3.13 mg/m(3), respectively. The effective irradiance of the welding arc outside the welding mask from high to low is manual welding (ZS60A electrode) , carbon dioxide shielded welding (907A flux-cored welding wire) , and argon shielded welding (JS80 welding wire) , respectively 1 010.7, 740.9, 589.5 μW/cm(2). The long-wave ultraviolet UVA intensity generated by argon shielded welding (JS80 welding wire) is the largest, which is 1 500 μW/cm(2). The content of Mn in the three welding operations is the highest, and JS80 welding wire has the highest Mn content of 128493.2 mg/kg. 907A flux cored wire has the highest Ti content, which is 24355.5mg/kg. The electrode ZS60A has the highest Cu content, which is 24422.12 mg/kg. Conclusion: The intensity of occupational hazards is different in the three kinds of welding operations, so the methods of personal protective equipment, field exposure assessment and health monitoring should be more targeted.
Air Pollutants, Occupational/analysis* ; Argon/analysis* ; Carbon Dioxide/analysis* ; Gases/analysis* ; Occupational Exposure/analysis* ; Welding/methods*

OBJECTIVETo evaluate the measurement uncertainty of welding fume in the air of the welding workplace of a shipyard, and to provide quality assurance for measurement.

METHODSAccording to GBZ/T 192.1-2007 "Determination of dust in the air of workplace-Part 1: Total dust concentration" and JJF 1059-1999 "Evaluation and expression of measurement uncertainty", the uncertainty for determination of welding fume was evaluated and the measurement results were completely described.

RESULTSThe concentration of welding fume was 3.3 mg/m(3), and the expanded uncertainty was 0.24 mg/m(3). The repeatability for determination of dust concentration introduced an uncertainty of 1.9%, the measurement using electronic balance introduced a standard uncertainty of 0.3%, and the measurement of sample quality introduced a standard uncertainty of 3.2%.

CONCLUSIONDuring the determination of welding fume, the standard uncertainty introduced by the measurement of sample quality is the dominant uncertainty. In the process of sampling and measurement, quality control should be focused on the collection efficiency of dust, air humidity, sample volume, and measuring instruments.

Air Pollutants, Occupational ; analysis ; standards ; Gases ; analysis ; Uncertainty ; Welding ; Workplace ; standards

OBJECTIVETo establish a method for determination of a variety of acid gas in the workplace air by Ion Chromatography. (hydrofluoric acid, hydrogen chloride or hydrochloric acid, sulfur anhydride or sulfuric acid, phosphoric acid, oxalic acid).

METHODThe sample in workplace air was collected by the porous glass plate absorption tube containing 5 ml leacheate. (Sulfuric acid fog, phosphoric acid aerosol microporous membrane after collection, eluted with 5 ml of eluent.) To separated by AS14+AG14 chromatography column, by carbonate (2.0+1.0) mmol/L (Na(2)CO(3)-NaHCO(3)) as eluent, flow rate of 1 ml/min, then analyzed by electrical conductivity detector. The retain time was used for qualitative and the peak area was used for quantitation.

RESULTSThe each ion of a variety of acid gas in the air of workplace were excellent in carbonate eluent separation. The linear range of working curve of 0∼20 mg/L. The correlation coefficient r>0.999; lower detection limit of 3.6∼115 µg/L; quantitative limit of 0.012∼0.53 mg/L; acquisition of 15L air were measured, the minimum detection concentration is 0.004 0∼0.13 mg/m(3). The recovery rate is 99.7%∼101.1%. In the sample without mutual interference ions. Samples stored at room temperature for 7 days.

CONCLUSIONThe same analysis method, the detection of various acidic gases in the air of workplace, simple operation, good separation effect, high sensitivity, high detection efficiency, easy popularization and application.

Acids, Noncarboxylic ; analysis ; Air ; analysis ; Air Pollutants, Occupational ; analysis ; Chromatography ; methods ; Gases ; Hydrochloric Acid ; Hydrofluoric Acid ; Ions ; analysis ; Limit of Detection ; Phosphoric Acids ; Sulfuric Acids ; Workplace

OBJECTIVES: We established a Wistar rat model of asthma caused by toluene diisocyanate (TDI) exposure, and investigated the relationship between TDI exposure concentrations and respiratory hypersensitivity, airway inflammation, and cytokine secretions in animals, to better understand the mechanism of TDI induced occupational asthma. METHODS: Wistar rats were exposed to two different concentrations of TDI vapor four hours a day for five consecutive days. Bronchoalveolar lavage (BAL) was performed, and differential leucocytes from the BAL fluid were analyzed. Lung histopathological examination was carried out to investigate the inflammatory status in the airways. Production of cytokines interleukin (IL)-4 and IL-5 productions in the BAL fluid in vivo was determined with enzyme-linked immunosorbent assay kits. RESULTS: The TDI-exposed rats exhibited greater airway hypersensitivity symptoms than the control rats. The BAL differential cell count and lung histopathological examination demonstrated that inflammation reactions were present in both the central and peripheral airways, characterized with marked infiltration of eosinophils in the TDI-exposed rats. The cytokine assay showed that IL-4 and IL-5 were predominantly produced in the BAL fluid in vivo. CONCLUSIONS: These findings imply that TDI exposure concentrations may greatly affect the occurrence and extent of inflammatory events and that Th2 type cytokines may play an important role in the immunopathogenesis of TDI-induced occupational respiratory hypersensitivity.
Animals ; Bronchoalveolar Lavage Fluid/chemistry/cytology ; Enzyme-Linked Immunosorbent Assay ; Eosinophils/cytology/immunology ; Female ; Gases/chemistry ; Hypersensitivity/pathology ; Interleukin-4/*analysis ; Interleukin-5/*analysis ; Lung/*drug effects/pathology/secretion ; Rats ; Rats, Wistar ; Toluene 2,4-Diisocyanate/*toxicity

Coal ; Dust ; analysis ; Gases ; adverse effects ; Humans ; Male ; Middle Aged ; Occupational Exposure ; analysis ; Pulmonary Alveolar Proteinosis ; etiology

Whether hydrogen and methane gas produced during lactulose breath test (LBT) are associated with symptoms of irritable bowel syndrome (IBS) is not determined. We aimed to investigate whether hydrogen and methane on LBT are associated with IBS symptoms. Sixty-eight IBS patients meeting the Rome III criteria for IBS, and 55 healthy controls, underwent LBT. The IBS subjects recorded their customary gastrointestinal symptoms on a questionnaire using visual analogue scales. LBT positivity was defined to be above 20 ppm rise of hydrogen or 10 ppm rise of methane within 90 min. Gas amounts produced during LBT were determined by calculating area under the curve of hydrogen and methane excretion. Symptom severity scores were not different between the LBT (+) IBS and LBT (-) IBS subjects and also between methane producers and non-methane producers. Gas amounts produced during LBT were not associated with IBS symptoms, except a weak correlation between total gas amounts and a few IBS symptoms such as bloating (r = 0.324, P = 0.039), flatulence (r = 0.314, P = 0.046) and abdominal pain (r = 0.364, P = 0.018) only in LBT (+) IBS. In conclusion, hydrogen and methane gas on LBT are not useful for predicting the customary symptoms and subtypes of IBS.
Abdominal Pain/etiology ; Adult ; Area Under Curve ; Breath Tests ; Female ; Flatulence/etiology ; Gases/analysis ; Humans ; Hydrogen/*analysis ; Irritable Bowel Syndrome/*diagnosis ; Lactulose/*metabolism ; Male ; Methane/*analysis ; Middle Aged ; ROC Curve ; Risk Factors

BACKGROUND: If acid-base status and electrolytes on blood gases during cardiopulmonary resuscitation (CPR) differ between the arrest causes, this difference may aid in differentiating the arrest cause. We sought to assess the ability of blood gases during CPR to predict the arrest cause between primary cardiac arrest and asphyxial arrest. METHODS: A retrospective study was conducted on adult out-of-hospital cardiac arrest patients for whom blood gas analysis was performed during CPR on emergency department arrival. Patients were divided into two groups according to the arrest cause: a primary cardiac arrest group and an asphyxial arrest group. Acid-base status and electrolytes during CPR were compared between the two groups. RESULTS: Presumed arterial samples showed higher potassium in the asphyxial arrest group (p < 0.001). On the other hand, presumed venous samples showed higher potassium (p = 0.001) and PCO2 (p < 0.001) and lower pH (p = 0.008) and oxygen saturation (p = 0.01) in the asphyxial arrest group. Multiple logistic regression analyses revealed that arterial potassium (OR 5.207, 95% CI 1.430-18.964, p = 0.012) and venous PCO2 (OR 1.049, 95% CI 1.021-1.078, p < 0.001) were independent predictors of asphyxial arrest. Receiver operating characteristic curve analyses indicated an optimal cut-off value for arterial potassium of 6.1 mEq/L (sensitivity 100% and specificity 86.4%) and for venous PCO2 of 70.9 mmHg (sensitivity 84.6% and specificity 65.9%). CONCLUSIONS: The present study indicates that blood gases during CPR can be used to predict the arrest cause. These findings should be confirmed through further studies.
Adult ; Asphyxia ; Blood Gas Analysis ; Cardiopulmonary Resuscitation ; Electrolytes ; Emergencies ; Gases ; Hand ; Heart Arrest ; Humans ; Hydrogen-Ion Concentration ; Logistic Models ; Out-of-Hospital Cardiac Arrest ; Oxygen ; Potassium ; Retrospective Studies ; ROC Curve ; Sensitivity and Specificity

OBJECTIVE:To test the efficacy and safety of PhilVent™, a pressure limited, time cycled, Philippine ventilator through animal and clinical studies.
METHODS AND RESULTS:
Animal study: Term, newborn piglets (N=8) were intubated and alternately cycled to the PhilVent™ or to a pressure limited, time cycled, commercial ventilator (Sechrist) at peak inspiratory pressures of 10, 13 and 15 cm H20 and rates of 15, 20, 25 breaths per min and constant FiO2 (0.40) and positive end expiratory pressure (+4). Blood gases and adverse events (pneumothorax, sudden deterioration, death) were monitored. Results show no significant difference in blood gases on either machine at the various ventilator settings. No adverse events occurred.
Clinical study: Prospective, randomized, controlled trial of 90 preterm infants with respiratory distress, randomized either to PhilVent™ (N=45) or Sechrist (N=45). Ventilator settings were adjusted to achieve predetermined range of blood gases. Arterial blood gases and any adverse events e.g., pneumothorax, pulmonary hemorrhage were monitored. There were no clinically significant differences in the ventilator settings or blood gases of the infants on the PhilVent™ or Sechrist. No increase in adverse events were noted with the PhilVent™.
CONCLUSION: In animal and clinical studies, the efficacy and safety of the PhilVent were comparable to the Sechrist. The PhilVent™ is an effective, alternative ventilator for the treatment of respiratory insufficiency in newborn infants.

Animal ; Male ; Female ; Infant Newborn ; Animals ; Blood Gas Analysis ; Gases ; Infant, Newborn ; Infant, Premature ; Philippines ; Pneumothorax ; Positive-pressure Respiration ; Prospective Studies ; Respiratory Insufficiency ; Ventilators, Mechanical ; Respiratory Distress Syndrome, Newborn ; Respiratory Insufficiency ; Equipment And Supplies

BACKGROUND: ASV is a closed-loop ventilation system that guarantees a user-set minimum per-minute volume in intubated patients, whether paralyzed or with spontaneous breathing. Here, we tested the effects of ASV onrespiratory mechanics and compared them with volume-controlled ventilation (VCV). METHODS: Thirteen patients meeting the criteria for acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) were enrolled. All patients were paralyzed to eliminate spontaneous breathing. We started with VCV (VCV1), then used ASV followed by VCV modes (VCV2), maintaining minute volume as much as that of VCV1. RESULTS: During ASV, compared with VCV1, the inspiratory and expiratory tidal volumes and expiratory resistance increased. Conversely, the total respiratory rate and maximum pressure decreased. No changes in the arterial blood gases, heart rate, or mean systemic pressure were noted during the trial. CONCLUSIONS: In ALI/ARDS patients, although no differences were observed in the arterial blood gas analysis between the two modes, ASV provided better respiratory mechanics in terms of peak airway pressure and tidal volume than VCV.
Acute Lung Injury ; Blood Gas Analysis ; Gases ; Heart Rate ; Humans ; Lung ; Mechanics ; Respiration ; Respiratory Mechanics ; Respiratory Rate ; Tidal Volume ; Ventilation

PURPOSE: To determine whether differences in arterial and end-tidal carbon dioxide [P(a-et)CO2], shock index, and serum lactate levels are helpful for predicting the outcome of resuscitation in hypovolemic shock patients in the emergency department. METHODS: A prospective study of end-tidal carbon dioxide (EtCO2)-derived variables and patient outcomes in hypovolemic shock was conducted in the emergency department of a university hospital from January 2005 to February 2006. A total of fifty-eight hypovolemic shock patients over 20 years old were included. During resuscitation, patients received volume replacement including blood transfusions, as well as vasopressor or inotropic therapy if needed. RESULTS: Twenty-one patients died in the hospital. At the time of admission (hour 0) and after resuscitation (hour 4), there were no differences related to age, respiration and heart rate, CVP, arterial blood gases, or EtCO2 between survivors and non-survivors. Non-survivors had significantly higher shock index scores, serum lactate levels, and P(a-et) CO2 than the survivors. The Receiver operator characteristic (ROC) curves at hour 4 hour for P(a-et)CO2 were as effective for predicting mortality as were the shock index and serum lactate levels. Shock index > 1.0, P(a-et)CO2 > 4 mmHg, and serum lactate > 5.0 mmol/L after resuscitation were all associated with a high early mortality rate (p=0.074, 0.001, 0.000, respectively). CONCLUSION: P(a-et)CO2, shock index, and serum lactate levels are predictive of in-hospital mortality and may be useful as guidelines in the resuscitation of hypovolemic shock patients in the emergency department.
Blood Gas Analysis ; Blood Transfusion ; Capnography ; Carbon Dioxide* ; Carbon* ; Emergency Service, Hospital ; Gases ; Heart Rate ; Hospital Mortality* ; Humans ; Hypovolemia* ; Lactic Acid* ; Mortality ; Prospective Studies ; Respiration ; Resuscitation* ; Shock* ; Survivors ; Young Adult