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A continuing challenge in occupational hygiene is that of estimating exposure to the multitude of airborne chemicals found in the workplace and surrounding community. Occupational exposure limits (OELs) have been established to prescribe the acceptable time weighted average for many different chemicals. Comparing the OELs to the measured workplace concentration allows occupational hygienists to assess the health risks and the need for control measures. Hence, methods to more effectively sample contaminants in the workplace are necessary to ensure that accurate exposure characterizations are completed. Evacuated canisters have been used for many years to collect ambient air samples for gases and vapors. Recently, increased interest has arisen in using evacuated canisters for personal breathing zone sampling as an alternative to sorbent samplers. A capillary flow control device was designed at McGill University mid 1990s. The flow control device was designed to provide a very low flow rate to allow a passive sample to be collected over an extended period of time. This research focused on the development and evaluation of a methodology to use a small canister coupled with the capillary flow controllers to collect long term time weighted air samples for gases and vapors. / A series of flow rate experiments were done to test the capillary flow capabilities with a 300 mL canister for sampling times ranging from a few minutes to over 40 hours. Flow rates ranging from 0.05 to 1.0 mL/min were experimentally tested and empirical formulae were developed to predict flow rates for given capillary geometries. The low flow rates allow for the collection of a long term air sample in a small personal canister. / Studies to examine the collection of air contaminants were conducted in laboratory and in field tests. Air samples for six volatile organic compounds were collected from a small exposure chamber using the capillary-canisters, charcoal tubes and diffusive badges at varied concentrations. The results from the three sampling devices were compared to each other and to concentration values obtained by an on-line gas chromatography. The results indicate that the capillary-canister compares quite favorably to the sorbent methods and to the on line GC values for the six compounds evaluated. / Personal air monitoring was conducted in a large exposure chamber to assess the effectiveness of the capillary-canister method to evaluate breathing zone samples. In addition, field testing was performed at a manufacturing facility to assess the long term monitoring capabilities of the capillary-canister. Precision and accuracy were found to parallel that of sorbent sampling methods. / The capillary-canister device displayed many positive attributes for occupational and community air sampling. Extended sampling times, greater capabilities to sample a broad range of chemicals simultaneously, ease of use, ease of analysis and the low relative cost of the flow controller should allow for improvements in exposure assessment.

Public international air law is not in itself an autonomous system. It follows the legal principles and notions applicable to public international law in general. The principle of good faith performance or enforcement of a contract, in particular, emphasizes faithfulness to an agreed common purpose and consistency with the justified expectations of the other party unless an expressed intention to the contrary has been declared. / By signing the Chicago Convention on International Civil Aviation of 1944, all 185 Contracting States agreed to certain principles and arrangements in order that international civil aviation could be developed in a safe and orderly manner. They undertook, inter alia, to collaborate in securing the highest practicable degree of uniformity in all matters in which such uniformity could facilitate and improve air navigation. Thus, they all agreed to a common purpose and to the means for ensuring it. / With the presence of several regulatory levels, namely, national, regional and international, and given the challenges of the new century in parallel with the increased sophistication of civil aviation systems, safety in air transportation requires that it be a shared responsibility. (Abstract shortened by UMI.)

The work describes the results obtained following the development and testing of a new device used to measure ventilation efficiency for indoor air quality (IAQ) in office buildings. The method uses concentration data obtained by the repeated injection of CO$ sb2$, used as a tracer gas simulating human respiration. The device measures the efficiency of the ventilation in reducing and evacuating pollutants. Ventilation efficiency was measured in a test chamber and was demonstrated in an office building. The method was tested to determine if it responded well to the effect of air flows, air velocities, air temperatures, number of diffusers and room temperatures. Results compared well with the theoretical predictions obtained from a two-chamber compartment model and could be predicted using simple regression models (r = 0.85). The work concludes that the new method can be used to measure ventilation efficiency and a chart is proposed for using the method with respect to recommended outdoor air flow rates in an office.

In the South African mining industry, the design of tunnel support systems is generally based on empirical methodologies that consider rockmass characteristics as well as the type of loading (e.g. seismic) that the excavation experiences. The design methodologies are by no means infallible, and work is continually being conducted to improve the classification of excavation conditions and thereby improve the selection of a suitable support system. This study is concerned with finding a means to monitor the installed support units rather than with improving the classification methodologies. It is postulated that with the extraction of accurate information describing the state of any support unit at any given time, areas of instability in the tunnel can be readily identified and strengthened~ Also, the information gathered as to the behaviour of the support units in a particular region can be used to assist in understanding the environmental characteristics of that region (rockmass, loading, etc.). A material survey was conducted to identify suitable candidates that could feasibly be used in either a passive (feedback when interrogated) or active (constant feedback) structural health monitoring system. The preferred candidates identified in this study are the group of passive smart materials referred to as TRIP steels, which are a subset of strain memory alloys. TRIP steels exhibit microstructural changes from paramagnetic austenite to ferromagnetic martensite as a function of increasing deformation at a given temperature.. The strength of the magnetic field at critical locations provides an indication as to the health state of the component. Because of their high strengths and ductility, TRIP steels can be used as what amounts to a self-monitoring support unit (interrogation apparatus required). Finite element methods are a practical means of predicting the mechanical and magnetostatic behaviour of TRIP steel structural members once material equations have been established by experiment. / Thesis (Ph.D.)-University of Natal, Durban, 2003.

This paper investigates in 2 studies the role of invulnerability in predicting young workers’ intentions to speak up about hazards. I propose a model in which perceptions of hazardous work are related to safety voice intentions via fear of injury, and that higher invulnerability buffers (a) the extent to which potential hazards generate fear of injury and (b) the extent to which fear of injury motivates voice. In Study 1, I randomly assigned participants (n = 115, aged 15-25) to an unsafe or safe scenario. Participants with lower invulnerability reported higher safety voice intentions across all levels of fear of injury. Participants with higher invulnerability reported as high safety voice intentions only when fear of injury was high, and reported much lower safety voice intentions than those with low invulnerability when fear of injury was low. Study 2 replicates this model using field data from young workers (n = 67).

Software product line engineering is a proposed methodology that enables software products and software-intensive systems to be developed at lower cost, higher quality and less time to market. The structured and managed artifacts reuse among different products in development is the main target of software product line engineering. As a key-method of the product line engineering approach, the commonality and variability analysis is a technique that identifies the potential artifacts for reuse. But the reuse poses challenges for delivering safety-critical products from the product line and achieving product line functional safety. In order to analyze the product line and provide more valuable information for its safety analysis, we make use of established product line modeling techniques, which model the product line commonality and variability from different perspectives. In this report, we investigate the product line modeling techniques. The product modeling analysis process covers two aspects: 1. Study different product line modeling techniques and find the ones suitable for product line modeling. We choose the modeling techniques that can be implemented to discuss in detail. 2. We implement the industrial wheel loader product line with two modeling techniques. Comprehensive models and detailed modeling process explanation are presented. The product line functional safety analysis covers three aspects: 1. Investigate the different safety analysis techniques and choose the fault tree analysis as the main technique. 2. Extend the single system fault tree to the product line fault tree. 3. Investigate the contributions of the product line modeling techniques to the product line functional safety analysis. Specifically, we map the product line models to the product line fault tree. Furthermore, we evaluate the product line modeling techniques from their performance in domain analysis and safety analysis.

With a primary focus on Health Canada (HC) and the Canadian Food Inspection Agency (CFIA), this thesis describes the state of microbial related public involvement and risk communication undertakings. The findings show that HC engages with experts to a far greater extent than with the lay public and that HC has not upheld its stated commitment to transparency. Furthermore, both HC’s and the CFIA´s approach to risk communication is overly general, has failed to provide opportunities for dialogue with vulnerable groups and is not rooted in foodborne surveillance data. Public involvement in food safety governance would be improved if HC provided the lay public with a seat on advisory committees and improved its reporting methods. HC and the CFIA could also make improvements by creating opportunities for dialogue between officials and the general public, and by exploring the potential use of alternative risk communication vehicles, such as food labels.

The purpose of this research is to examine the effectiveness of the Bill C-45 amendments to the Criminal Code in addressing workplace fatality incidents. This research involved both qualitative and quantitative research and utilized two research methods. The first method involved a secondary analysis of thirty-eight Incident Investigation Reports completed by WorkSafeBC. These were supplemented with additional case information about these incidents provided via the Freedom of Information offices in British Columbia. The second method utilized nine semi-structured interviews with respondents in the field of occupational health and safety and corporate criminality who were familiar with the Bill C-45 amendments. The study found that employers could be found liable in half of the cases examined; that there appeared to be unique characteristics of British Columbia that effect the use of criminal charges; that the criminal law is not very effective in cases of criminal negligence for workplace fatality; and that improvements could be made to the criminal law.

Para-hydroxybenzyl isothiocyanate (p-HBIT) formed in yellow mustard following hydrolysis of the glucosinolate, sinalbin, is a natural antimicrobial agent. p-HBIT is not dependably available commercially, and a small amount was synthesized for use in beaker sausage fermentations. For these trials stabilized p-HBIT was used in dry sausage meat batter to reduce the viability of inoculated Escherichia coli O157:H7. A >4 log CFU/g reduction of E. coli O157:H7 was achieved in the beaker sausage containing p-HBIT. For sensory evaluation of fermented sausages containing ≤ 4% (w/w) yellow mustard powder, consumer preference tests were done. Deodorized (deheated) yellow mustard was added at 1,2,3 and 4% (w/w) to dry-fermented sausage and it was found that 3% and 4% mustard negatively affected the flavour, texture and overall acceptability of the fermented sausage. Dry-fermented sausage containing 1% and 2% mustard had a slight change in flavour, texture and overall acceptability.