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1.
Fed Regist ; 81(223): 81685-97, 2016 Nov 18.
Article in English | MEDLINE | ID: mdl-27906532

ABSTRACT

The Food and Drug Administration (FDA or the Agency) is amending its current good manufacturing practice (CGMP) and labeling regulations regarding medical gases. FDA is requiring that portable cryogenic medical gas containers not manufactured with permanent gas use outlet connections have gas-specific use outlet connections that cannot be readily removed or replaced except by the manufacturer. FDA is also requiring that portable cryogenic medical gas containers and high-pressure medical gas cylinders meet certain labeling, naming, and color requirements. These requirements are intended to increase the likelihood that the contents of medical gas containers are accurately identified and reduce the likelihood of the wrong gas being connected to a gas supply system or container. FDA is also revising an existing regulation that conditionally exempts certain medical gases from certain otherwise-applicable labeling requirements in order to add oxygen and nitrogen to the list of gases subject to the exemption, and to remove cyclopropane and ethylene from the list.


Subject(s)
Equipment Safety/standards , Gases/standards , Manufactured Materials/standards , Product Packaging/legislation & jurisprudence , Cyclopropanes , Equipment Design , Ethylenes , Humans , Nitrogen , Oxygen , Product Labeling/standards , Product Packaging/standards , United States , United States Food and Drug Administration
2.
J Occup Health ; 58(5): 452-459, 2016 Sep 30.
Article in English | MEDLINE | ID: mdl-27488036

ABSTRACT

OBJECTIVES: Ultraviolet radiation (UVR) emitted during arc welding frequently causes keratoconjunctivitis and erythema in the workplace. The degree of hazard from UVR exposure depends on the welding method and conditions. Therefore, it is important to identify the UVR levels present under various conditions. METHODS: We experimentally evaluated the UVR levels emitted in gas metal arc welding (GMAW) of mild steel. We used both a pulsed welding current and a non-pulsed welding current. The shielding gases were 80% Ar + 20% CO2 and 100% CO2. The effective irradiance defined in the American Conference of Governmental Industrial Hygienists guidelines was used to quantify the UVR hazard. RESULTS: The effective irradiance measured in this study was in the range of 0.51-12.9 mW/cm2 at a distance of 500 mm from the arc. The maximum allowable exposure times at these levels are only 0.23-5.9 s/day. CONCLUSIONS: The following conclusions were made regarding the degree of hazard from UVR exposure during the GMAW of mild steel: (1) It is more hazardous at higher welding currents than at lower welding currents. (2) At higher welding currents, it is more hazardous when 80% Ar + 20% CO2 is used as a shielding gas than when 100% CO2 is used. (3) It is more hazardous for pulsed welding currents than for non-pulsed welding currents. (4) It appears to be very hazardous when metal transfer is the spray type. This study demonstrates that unprotected exposure to UVR emitted by the GMAW of mild steel is quite hazardous.


Subject(s)
Air Pollutants, Occupational/analysis , Gases/analysis , Occupational Exposure/analysis , Ultraviolet Rays , Air Pollutants, Occupational/adverse effects , Environmental Monitoring , Gases/adverse effects , Gases/standards , Humans , Occupational Exposure/adverse effects , Occupational Exposure/standards , Occupational Health , Risk Assessment , Steel , Ultraviolet Rays/adverse effects , Welding
3.
J Chromatogr A ; 1375: 140-5, 2015 Jan 02.
Article in English | MEDLINE | ID: mdl-25526978

ABSTRACT

A novel method for the analysis of total sulphur-containing impurities in a hydrogen matrix has been developed. This method has a limit of detection (LoD) significantly lower than that maximum amount fraction for sulphur-containing compounds (4 nmol mol(-1)) specified by the international standard for hydrogen to be used in fuel cell vehicles (ISO 14687-2). To measure the LoD for this method, a novel gas standard containing five different sulphur-containing compounds at low nmol mol(-1) amount fractions has been gravimetrically prepared. Stable primary gas standards that are traceable to the SI were used to successfully validate the amount fractions of the sulphur-containing compounds in this gas standards using gas chromatography with flame ionisation detection (GC-FID) and sulphur chemiluminescence detection (GC-SCD).


Subject(s)
Flame Ionization/methods , Hydrogen , Luminescent Measurements , Sulfur Compounds/analysis , Flame Ionization/standards , Gases/standards , Reference Standards
4.
Talanta ; 111: 111-8, 2013 Jul 15.
Article in English | MEDLINE | ID: mdl-23622533

ABSTRACT

An UV-Ion Mobility Spectrometer is a simple, rapid, inexpensive instrument widely used in environmental analysis among other fields. The advantageous features of its underlying technology can be of great help towards developing reliable, economical methods for determining gaseous compounds from gaseous, liquid and solid samples. Developing an effective method using UV-Ion Mobility Spectrometry (UV-IMS) to determine volatile analytes entails using appropriate gaseous standards for calibrating the spectrometer. In this work, two home-made sample introduction systems (SISs) and a commercial gas generator were used to obtain such gaseous standards. The first home-made SIS used was a static head-space to measure compounds present in liquid samples and the other home-made system was an exponential dilution set-up to measure compounds present in gaseous samples. Gaseous compounds generated by each method were determined on-line by UV-IMS. Target analytes chosen for this comparative study were ethanol, acetone, benzene, toluene, ethylbenzene and xylene isomers. The different alternatives were acceptable in terms of sensitivity, precision and selectivity.


Subject(s)
Gases/analysis , Spectrum Analysis/methods , Ultraviolet Rays , Volatile Organic Compounds/analysis , Acetone/analysis , Acetone/chemistry , Benzene/analysis , Benzene/chemistry , Benzene Derivatives/analysis , Benzene Derivatives/chemistry , Calibration , Ethanol/analysis , Ethanol/chemistry , Gases/chemistry , Gases/standards , Ions/chemistry , Reference Standards , Reproducibility of Results , Spectrum Analysis/instrumentation , Toluene/analysis , Toluene/chemistry , Volatile Organic Compounds/chemistry , Volatile Organic Compounds/standards , Xylenes/analysis , Xylenes/chemistry
5.
Appl Radiat Isot ; 70(9): 1934-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22607994

ABSTRACT

The Korea Research Institute of Standards and Science (KRISS) has developed a primary system for the activity standardization of gaseous radon-222, based on the defined solid angle counting method. The size of adsorbed radon is determined by a Cyclone Storage Phosphor System, and a buffer chamber is introduced between the measurement chamber and the source for the purpose of gas purification. The measured activity of gaseous radon-222 and its associated measurement uncertainty obtained using the system are presented.


Subject(s)
Gases/chemistry , Gases/standards , Radiometry/instrumentation , Radiometry/standards , Radon/chemistry , Radon/standards , Gases/analysis , Half-Life , Internationality , Radiation Dosage , Radon/analysis , Reference Standards , Reference Values , Republic of Korea
6.
Appl Radiat Isot ; 70(9): 2063-5, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22516716

ABSTRACT

A prototype of a calibration facility for noble gas monitoring using (41)Ar in the PTKMR-BATAN has been tested. The facility was designed in such a way that the standard source of gas can be reused. The radioactive (41)Ar source was obtained by thermal neutron reaction of (40)Ar(n, γ)(41)Ar using a thermal neutron flux of 4.8×10(13) neutrons per cm(2) per second in two minutes on the multipurpose G.A. Siwabessy Reactor (Batan, Serpong, Indonesia). Gamma spectrometry was used to measure the radioactivity and purity of (41)Ar. The spectrum of the (41)Ar observed yields an energy of 1294 keV because of the highest intensity (99.2%). The activity of (41)Ar was 2821 kBq and 4% of the expanded uncertainty. The time required for (41)Ar to reach homogeneity was 7 min, and the effectiveness of resuse was 53%.


Subject(s)
Argon/analysis , Argon/standards , Gases/standards , Radioisotopes/analysis , Radioisotopes/standards , Radiometry/instrumentation , Radiometry/standards , Calibration , Equipment Design , Equipment Failure Analysis , Gases/analysis , Half-Life , Internationality , Radiation Dosage , Reference Standards , Reference Values
7.
Chem Senses ; 35(6): 523-30, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20507921

ABSTRACT

Human odor and mucosal membrane irritation thresholds are used as criteria for assessing air quality in occupational and environmental settings. Unfortunately, reported threshold values still differ by several orders of magnitude rendering most standard compilations of little practical utility. Thus, in view of the need to repeat odor threshold measurements with a reliable methodology, a new technical approach based on original equipment manufacturer integrated solutions is presented. To test applicability, a calibration gas generator was used to continuously generate a fixed odor vapor concentration. Different dilution steps were realized by coupling to a purchasable olfactometer. Comparison with the "standard," that is, odor stimulus supply via sample bags revealed good correspondence. As a second step, the calibration gas generator was used to generate rapid changes in stimulus concentration between consecutive trials. Irritation thresholds were measured with an ascending series of ammonia concentrations generated from an aqueous solution. The obtained thresholds lay within the range previously reported. The introduced technology enables quick and reliable odor stimulus generation and provides flexibility in choosing the optimal start concentration, the step-size between dilutions, and the range of stimulus concentrations. Errors from usage of rotameters or sample bags can be avoided.


Subject(s)
Gases/chemistry , Odorants , Sensory Thresholds/physiology , Adult , Ammonia/chemistry , Ammonia/pharmacology , Calibration , Gases/standards , Humans , Male , Middle Aged , Smell/physiology
8.
Health Devices ; 39(1): 27-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20143660

ABSTRACT

The use of industrial-grade gases instead of medical-grade gases for clinical applications increases the risk of introducing undesirable and even toxic contaminants into the clinical environment. Hospitals should have policies in place to ensure that gases of the appropriate type and grade are used for the intended application.


Subject(s)
Accidents, Occupational/prevention & control , Chemical Industry/standards , Equipment Contamination/prevention & control , Gases/standards , Health Facilities/standards , Air Pollutants, Occupational/poisoning , Humans , Nitrogen/analysis
9.
Anal Chem ; 82(3): 859-67, 2010 Feb 01.
Article in English | MEDLINE | ID: mdl-20052968

ABSTRACT

Studies of climate change increasingly recognize the diverse influences exerted by hydrocarbons in the atmosphere, including roles in particulates and ozone formation. Measurements of key non-methane hydrocarbons (NMHCs) suggest atmospheric concentrations ranging from low pmol/mol to nmol/mol, depending on location and compound. To accurately establish concentration trends and to relate measurement records from many laboratories and researchers, it is essential to have good calibration standards. Several of the world's National Metrology Institutes (NMIs) are developing primary and secondary reference gas standards at the nmol/mol level. While the U.S. NMI, the National Institute of Standards and Technology (NIST), has developed pmol/mol standards for halocarbons and some volatile organics, the feasibility of preparing well-characterized, stable standards for NMHCs at the pmol/mol level is not yet established. NIST recently developed a suite of primary standards by gravimetric dilution that contains 18 NMHCs covering the concentration range of 60 pmol/mol to 230 pmol/mol. Taking into account the small but chemically significant contribution of NMHCs in the high-purity diluent nitrogen used in their preparation, the relative concentrations and short-term stability (2 to 3 months) of these NMHCs in the primary standards have been confirmed by chromatographic analysis. The gravimetric values assigned from the methods used to prepare the materials and the analytical concentrations determined from chromatographic analysis generally agree to within +/-2 pmol/mol. However, anomalous results for several of the compounds reflect the difficulties inherent in avoiding contamination and making accurate measurements at these very low levels.


Subject(s)
Chromatography, Gas/standards , Gases/standards , Hydrocarbons/standards , Chromatography, Gas/methods , Climate Change , Environmental Monitoring , Gases/analysis , Hydrocarbons/analysis , Hydrocarbons/chemistry , Ozone/metabolism , Reference Standards
10.
Health Devices ; 39(8): 293-4, 2010 Aug.
Article in English | MEDLINE | ID: mdl-21305904

ABSTRACT

Contaminated gas supplies present a risk to clinical staff and patients, with serious and possibly even fatal consequences. Hospitals should have policies in place so that staff can react quickly in the event of gas contamination or other gas-related emergencies.


Subject(s)
Drug Contamination/prevention & control , Equipment Contamination/prevention & control , Gases/standards , Disaster Planning , Humans , Nitrogen/adverse effects , Nitrogen/standards
11.
Philos Trans A Math Phys Eng Sci ; 363(1834): 2165-75, 2005 Sep 15.
Article in English | MEDLINE | ID: mdl-16147504

ABSTRACT

An ongoing challenge in physics is to make increasingly accurate measurements of physical quantities. Bose-Einstein condensates in atomic gases are ideal candidates for use in precision measurement schemes since they are extremely cold and have laser-like coherence properties. In this paper, we review these two attributes and discuss how they could be exploited to improve the resolution in a range of different measurements.


Subject(s)
Gases/chemistry , Gases/standards , International System of Units/standards , Physics/standards , Quantum Theory , Reference Standards , Reference Values , Computer Simulation , Gases/analysis , Internationality , Models, Statistical , Reproducibility of Results , Sensitivity and Specificity
12.
J Anim Sci ; 83(3): 686-93, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15705766

ABSTRACT

Two experiments were conducted to examine the effects of hot boning, modified atmosphere packaging, and injection enhancement on the oxidative and sensory properties of beef round muscles. The beef knuckle (quadriceps muscles) was partially hot boned within 1.5 h postmortem from one randomly selected side of each beef carcass (n = 14), whereas the quadriceps on the opposite side remained intact throughout a 48-h chilling period. At 5 d postmortem, biceps femoris, semimembranosus, vastus lateralis, and rectus femoris muscles from both hot- and cold-boned sides were injected with an enhancement solution consisting of water, salt, phosphate, and natural flavorings (rosemary) at either 6 (Exp. 1) or 10% (Exp. 2) of fresh muscle weight. Enhanced muscles were then processed into 2.54-cm-thick steaks, which were allotted randomly to high-oxygen (HiOx; 80% O2:20% CO2) or ultra-low oxygen (LoOx; 80% N2:20% CO2) modified atmosphere packaging. Regardless of hot boning or enhancement, steaks packaged in LoOx had lower thiobarbituric acid-reactive substances values (P < 0.05), more beef flavor intensity (P < 0.05), fewer off flavors (P < 0.05), and were more tender (P < 0.05) than steaks packaged in HiOx. Hot boning the knuckle had no effect on oxidative (P > or = 0.99) and sensory properties (P > or = 0.85). Increasing the level of injection enhancement from 6 to 10% introduced more rosemary and phosphate into the muscles, thereby decreasing the extent of oxidation, but also imparting a nontypical beef flavor. Packaging in LoOx atmosphere offered the optimal result of decreased oxidation and improved tenderness, without detriment to flavor. Injection enhancement (both 6 and 10%) created off-flavors attributable to the enhancement solution; however, the 10% injection seemed to offer more resistance to lipid oxidation.


Subject(s)
Food Handling/methods , Food Handling/standards , Food Packaging/methods , Food Packaging/standards , Meat/standards , Animals , Bone and Bones , Cattle , Gases/analysis , Gases/standards , Hot Temperature , Humans , Hydrogen-Ion Concentration , Injections/standards , Least-Squares Analysis , Male , Muscle, Skeletal/chemistry , Oxidation-Reduction , Random Allocation , Taste , Thiobarbituric Acid Reactive Substances/analysis , Time Factors
13.
Appl Spectrosc ; 58(12): 1452-61, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15606959

ABSTRACT

The National Institute of Standards and Technology (NIST) and the Pacific Northwest National Laboratory (PNNL) are each creating quantitative databases containing the vapor-phase infrared spectra of pure chemicals. The digital databases have been created with both laboratory and remote-sensing applications in mind. A spectral resolution of approximate, equals 0.1 cm(-1) was selected to avoid degrading sharp spectral features, while also realizing that atmospheric broadening typically limits line widths to 0.1 cm(-1). Calculated positional (wave- number, cm(-1)) uncertainty is /=9) path length-concentration burdens and fitting a weighted Beer's law plot to each wavenumber channel. The two databases include different classes of compounds and were compared using 12 samples. Though these 12 samples span a range of polarities, absorption strengths, and vapor pressures, the data agree to within experimental uncertainties with only one exception.


Subject(s)
Databases, Factual , Gases/analysis , Gases/standards , Reference Standards , Spectroscopy, Fourier Transform Infrared/methods , Spectroscopy, Fourier Transform Infrared/standards , Calibration/standards , Gases/chemistry , Phase Transition , Reference Values , Reproducibility of Results , Sensitivity and Specificity , Spectroscopy, Fourier Transform Infrared/instrumentation , United States
14.
J Chromatogr A ; 1033(1): 145-51, 2004 Apr 09.
Article in English | MEDLINE | ID: mdl-15072299

ABSTRACT

The new type of silica gel surface modification with using the trimethylamine as a reagent is described. The samples of chemically modified silica gel have been used for generation of gaseous standard mixtures (methyl chloride as a measurand) using the technique of thermal decomposition of the surface compound. The main aim of the research was to check the suitability of the new type of silica gel surface modification for obtaining methyl chloride as a measurand of gaseous standard mixture. The gaseous standard mixture obtained with using this technique was used for calibration of a thermal desorber-gas chromatography-flame ionization detector (TD-GC-FID) system. The homogeneity of coverage of silica gel surface with the immobilized compound has been evaluated. The full uncertainty budget of determination of liberated amount of methyl chloride has been calculated. The average amount of methyl chloride liberated from the unit sample of chemically modified silica gel is 3.59 +/- 0.13 mg g(-1). The influence of the modification way on the amount of liberated analyte has also been determined.


Subject(s)
Gases/standards , Silicon Dioxide/chemistry , Calibration , Silica Gel , Temperature
15.
Occup Health Saf ; 73(2): 12, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15024900
16.
Appl Radiat Isot ; 60(2-4): 387-90, 2004.
Article in English | MEDLINE | ID: mdl-14987672

ABSTRACT

In the past few years, a primary measurement system has been established at the PTB allowing absolute measurements of 222Rn. The activity can be determined by counting the emitted alpha particles in a defined solid angle after condensing the radon at a cold point under vacuum conditions. This primary measurement system is connected to a solid 226Ra source, where 222Rn can be produced up to an activity of about 2MBq. After the measurement, radon can be completely transferred into a glass bulb or a stainless steel cylinder for use as a transfer standard. The results of the measurements, the uncertainties and the realization of the primary measurement system are described. For quality assurance and fast determination of radon activity, a secondary measurement system with an NaI(Tl) detector is also used. Together, both systems provide a reliable tool for the production of gaseous 222Rn activity standards with relative uncertainties of less than 1%.


Subject(s)
Alpha Particles , Gases/analysis , Gases/standards , Radiometry/methods , Radiometry/standards , Radon/analysis , Radon/standards , Half-Life , Quality Control , Radiation Dosage , Radon Daughters/analysis , Radon Daughters/standards , Reference Standards , Reproducibility of Results , Sensitivity and Specificity
17.
Sens Actuators B Chem ; 93(1-3): 7-16, 2003 Aug 01.
Article in English | MEDLINE | ID: mdl-14584511

ABSTRACT

The ability to monitor air contaminants in the shuttle and the International Space Station is important to ensure the health and safety of astronauts, and equipment integrity. Three specific space applications have been identified that would benefit from a chemical monitor: (a) organic contaminants in space cabin air; (b) hypergolic propellant contaminants in the shuttle airlock; (c) pre-combustion signature vapors from electrical fires. NASA at Kennedy Space Center (KSC) is assessing several commercial and developing electronic noses (E-noses) for these applications. A short series of tests identified those E-noses that exhibited sufficient sensitivity to the vapors of interest. Only two E-noses exhibited sufficient sensitivity for hypergolic fuels at the required levels, while several commercial E-noses showed sufficient sensitivity of common organic vapors. These E-noses were subjected to further tests to assess their ability to identify vapors. Development and testing of E-nose models using vendor supplied software packages correctly identified vapors with an accuracy of 70-90%. In-house software improvements increased the identification rates between 90 and 100%. Further software enhancements are under development. Details on the experimental setup, test protocols, and results on E-nose performance are presented in this paper along with special emphasis on specific software enhancements.


Subject(s)
Air Pollutants/analysis , Air Pollution, Indoor/analysis , Environmental Monitoring/instrumentation , Gases/analysis , Life Support Systems/instrumentation , Space Flight/standards , Air Pollutants/classification , Air Pollutants/standards , Atmospheric Pressure , Ecological Systems, Closed , Equipment Design , Evaluation Studies as Topic , Gases/classification , Gases/standards , Pattern Recognition, Automated , Sensitivity and Specificity , Smoke/analysis , Space Flight/instrumentation , Spacecraft/instrumentation
18.
Ann Pharm Fr ; 60(5): 326-32, 2002 Sep.
Article in French | MEDLINE | ID: mdl-12378142

ABSTRACT

In 1989, a European directive extended the definition of proprietary medicinal products, and consequently the necessity to hold a marketing authorization (MA), for all industrially manufactured products, including medicinal gases. In France, the directive 89/341/CEE was transposed in the French law on December 8(th), 1992 and France was the first Member State to implement provisions for the obtention of MAs for gases for medical use. Since then, France has stayed at the forefront in this area. Following the inclusion of gases in the scope of pharmaceutical products, gases require on MA obtained following the same methods as for drugs and be manufactured and distributed in authorized sites. Moreover, the European directive has led the French authorities to classify gases according to their use. Gases for medical use are thus considered either as medicinal products or as medical devices.


Subject(s)
Gases/standards , Drug Compounding/standards , European Union , France , Humans , Legislation, Drug
19.
Anal Chem ; 74(1): 305-7, 2002 Jan 01.
Article in English | MEDLINE | ID: mdl-11795812

ABSTRACT

Permeation tubes are convenient analyte sources for generating standard gas mixtures (containing, in particular, volatile organic compounds) used in the calibration of analytical instruments. For small permeation rates, corresponding to trace levels of analytes, the calibration of permeation tubes is time-consuming. The use of thermogravimetry as a means to measure rapidly the weight loss at constant temperature was investigated. An attempt to apply this technique to calibrating a permeation tube filled with benzene is described. In the 20 ng/min range of permeation rate, day-to-day variations of <5% were observed. The continuous weight loss monitoring of permeation tubes by thermogravimetry allows their rapid characterization.


Subject(s)
Air Pollutants/analysis , Environmental Monitoring/instrumentation , Air Pollutants/standards , Environmental Monitoring/standards , Gases/standards , Organic Chemicals/analysis , Reference Standards
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