This thesis is concerned with the identification, elimination and reduction of barriers to the use of personal respiratory protective equipment (RPE) in the workplace to reduce and prevent occupational inhalation disease. Respiratory Protective Equipment (RPE) is widely used in industry, health, emergency response, military settings and many other applications and are in daily use by thousands of people in Australasia. The equipment is generally used to filter or ab/adsorb the contaminants from the air prior to delivery to the wearer by filtering or ad/absorbing contaminants from the air prior to being breathed. There is increasing concerns being expressed worldwide as well as in Australia and New Zealand about the apparent increase in diagnosed occupational diseases and the use of RPE is an essential preventative measure able to be adopted by workplaces. The use of this type of equipment is the option after the preferred options of elimination and isolation of the individual from the contaminant in the atmosphere. In spite of this, many different types of RPE are routinely in use. There are, however, enormous practical, physiological and psychological difficulties in the wearing of RPE. Concerns have been expressed in the literature as well as in practical situations that many different types of RPE was unable to meet the needs of workers, particularly as related to airflows and that current standards did not reflect the real-life workplace demands. This work set out to determine an improved methodology for users to determine the total inward leakage (TIL), the different types and quantities of airflows, particularly Peak Inspiratory Air Flows (PIAF). When communicating (an essential aspect in the workplace for safety reasons), PIAFs rise dramatically. This work showed that PIAF were very high, particularly when communicating, and is likely to exceed the ability of many commercial types of commercially available respiratory equipment as well being in excess of the certification requirements of standard bodies. In addition, Minute Volumes (MV) in a typical Australian workforce were shown to be very variable between individuals and current certification requirement of airflows do not appear to reflect practical use. The thesis further investigated using a questionnaire survey, the knowledge and current intervention measures adopted by farmers in different sections of agriculture, particularly dairy farming. Agriculture in New Zealand is a critical economic activity, employing 10% of the total workforce. This work showed that in spite of many different types of intervention activity spread over many years by Government agencies and private organisations to date, limited awareness exists of inhalation diseases and appropriate types of RPE in different applications (for example, confined space applications). The research would suggest that a different and more intensive approach is needed by Government agencies to address the problem in this workplace community if workplace inhalation diseases are to be reduced in the future.

This thesis is concerned with the identification, elimination and reduction of barriers to the use of personal respiratory protective equipment (RPE) in the workplace to reduce and prevent occupational inhalation disease. Respiratory Protective Equipment (RPE) is widely used in industry, health, emergency response, military settings and many other applications and are in daily use by thousands of people in Australasia. The equipment is generally used to filter or ab/adsorb the contaminants from the air prior to delivery to the wearer by filtering or ad/absorbing contaminants from the air prior to being breathed. There is increasing concerns being expressed worldwide as well as in Australia and New Zealand about the apparent increase in diagnosed occupational diseases and the use of RPE is an essential preventative measure able to be adopted by workplaces. The use of this type of equipment is the option after the preferred options of elimination and isolation of the individual from the contaminant in the atmosphere. In spite of this, many different types of RPE are routinely in use. There are, however, enormous practical, physiological and psychological difficulties in the wearing of RPE. Concerns have been expressed in the literature as well as in practical situations that many different types of RPE was unable to meet the needs of workers, particularly as related to airflows and that current standards did not reflect the real-life workplace demands. This work set out to determine an improved methodology for users to determine the total inward leakage (TIL), the different types and quantities of airflows, particularly Peak Inspiratory Air Flows (PIAF). When communicating (an essential aspect in the workplace for safety reasons), PIAFs rise dramatically. This work showed that PIAF were very high, particularly when communicating, and is likely to exceed the ability of many commercial types of commercially available respiratory equipment as well being in excess of the certification requirements of standard bodies. In addition, Minute Volumes (MV) in a typical Australian workforce were shown to be very variable between individuals and current certification requirement of airflows do not appear to reflect practical use. The thesis further investigated using a questionnaire survey, the knowledge and current intervention measures adopted by farmers in different sections of agriculture, particularly dairy farming. Agriculture in New Zealand is a critical economic activity, employing 10% of the total workforce. This work showed that in spite of many different types of intervention activity spread over many years by Government agencies and private organisations to date, limited awareness exists of inhalation diseases and appropriate types of RPE in different applications (for example, confined space applications). The research would suggest that a different and more intensive approach is needed by Government agencies to address the problem in this workplace community if workplace inhalation diseases are to be reduced in the future.

En els darrers anys ha augmentat de manera considerable l'interès de les empreses per l'ús de materials reciclats per a la fabricació dels seus productes. Les raons principals són l'estalvi econòmic que comporta a causa del progressiu increment del preu de la matèria primera i l'aposta per una política ambiental d'empresa, com a part de la seva responsabilitat social corporativa, en sintonia amb una sensibilitat creixent en l'opinió pública.Aquesta tesi s'ha centrat en l'estudi de la viabilitat de la utilització de materials termoplàstics reciclats per a aplicacions en el sector de l'electrònica de consum. En una primera part, s'ha estudiat la viabilitat de la substitució dels materials verges poliestirè antixoc (HIPS) i la mescla de polímers poli(èter de fenilè) amb poliestirè antixoc (PPE/HIPS) pels mateixos materials d'origen reciclat, procedents de residus industrials. En una segona part, s'ha estudiat la viabilitat de substitució dels mateixos materials verges, estudiats en la primera part, per un material reciclat diferent. Aquest material reciclat ha estat el poli(tereftalat d'etilè)(PET) provinent de la recollida selectiva d'envasos de begudes postconsum. El treball de recerca ha estudiat la variació de propietats mecàniques i tèrmiques dels materials reciclats de partida i de les mescles de material verge i reciclat, els efectes de la degradació provocats pels processos successius de transformació i la influència de càrregues minerals (fibres i microesferes de vidre) i ignifugants a base de fòsfor lliures d'halògens sobre les propietats dels materials. L'estudi realitzat sobre aquests tres materials reciclats ha permès analitzar els factors que intervenen en l'estudi de materials reciclats, conèixer-ne les possibilitats d'aplicació en el cas concret de components d'electrònica de consum i crear les bases per poder establir una metodologia per realitzar futurs estudis d'introducció de materials reciclats en altres aplicacions tecnològiques. / En los últimos años ha aumentado de manera considerable el interés de las empresas por el uso de materiales reciclados para la fabricación de sus productos. Las razones principales son el ahorro económico que conlleva a causa del progresivo incremento del precio de la materia prima y la apuesta por una política medioambiental de empresa, como parte de su responsabililidad social corporativa, en sintonía con una sensibilidad creciente en la opinión pública.Esta tesis se ha centrado en el estudio de la viabilidad de la utilización de materiales termoplásticos reciclados para aplicaciones en el sector de la electrónica de consumo. En una primera parte, se ha estudiado la viabilidad de la sustitución de los materiales vírgenes poliestireno antichoque (HIPS) y la mezcla de polímeros poli(éter de fenileno) con poliestireno antichoque (PPE/HIPS) por los mismos materiales de origen reciclado, procedentes de residuos industriales. En una segunda parte, se ha estudiado la viabilidad de sustitución de los mismos materiales vírgenes, estudiados en la primera parte, por un material reciclado diferente. Este material reciclado ha sido el poli(tereftalato de etileno) (PET) procedente de la recogida selectiva de envases de bebidas postconsumo.El trabajo de investigación ha estudiado la variación de propiedades mecánicas y térmicas de los materiales reciclados de partida y de las mezclas de material virgen y reciclado, los efectos de la degradación provocados por los procesos sucesivos de transformación y la influencia de cargas minerales (fibras y microesferas de vidrio) y ignifugantes a base de fósforo libres de halógenos sobre las propiedades de los materiales.El estudio realizado sobre estos tres materiales reciclados ha permitido analizar los factores que intervienen en el estudio de materiales reciclados, conocer las posibilidades de su aplicación en el caso concreto de componentes de electrónica de consumo y crear las bases para poder establecer una metodología para realizar futuros estudios de introducción de materiales reciclados en otras aplicaciones tecnológicas. / In recent years the interest of companies in the use of recycled materials for the manufacture of their products has increased considerably. The main reasons for this are, firstly, the economic savings offered when compared to the progressive increase in the price of the raw material and secondly, the pressure for a company to implement an environmental policy, as part of its 'corporate social responsibility', in tune with a growing sensitivity of public opinion in this area. This thesis has focussed on studying the feasibility of the use of recycled thermoplastic materials for applications in the consumer electronics sector. In the first part, it centres on the feasibility of the substitution of the virgin materials High-Impact Polystyrene (HIPS) and the mix of polymers poly(ether phenylene) with High-Impact Polystyrene (PPE/HIPS), for the same materials of recycled origin, coming from industrial waste. In the second part, it studies the feasibility of substitution of the virgin materials studied in the first part, by a different recycled material. This recycled material being the pol (ethylene terephtalat) (PET) which comes from the selective collection of post consumption drink bottles. The research work has studied the variation of mechanical and thermal properties of the original recycled materials and of the mixtures of virgin and recycled material, the effects of the degradation provoked by the successive transformation processes and the influence of mineral fillers (fibres and glass beads) and halogen-free phosphor-based flame retardants, on the properties of the materials. The study, carried out on these three recycled materials, has allowed the following: analysis of the factors that intervene in the investigation of recycled materials; knowledge regarding the possibilities of application in the case of household electronics components and it has created the bases for being able to establish a methodology for carrying out future studies on the introduction of recycled materials in other technological applications.

No description available.

Healthcare providers encounter a wide range of hazards on the job, including exposure to infectious diseases. Protecting them from occupational infectious disease is very important. Healthcare workers use personal protective equipment (PPE) as a measure to decrease the risk of getting infected during patient care. For high-risk diseases like Ebola, Tyvek suits are coverall suits that protect the body and reduce the risk of body fluid exposure. However, a person removing a contaminated suit may also be exposed to virus. Previous studies have shown that enveloped viruses can survive on different types of surfaces, so the objective of this study is to determine the inactivation of bacteriophage Φ6, a surrogate for enveloped human virus, on the surface of Tyvek suits at two different relative humidity levels, 40% and 60% at 22°C. The results showed the inactivation rate of virus was higher at 60% RH than 40% RH. There was ~3log10 (99.9%) reduction of virus inactivation after 6 hours at 40% but ~3log10 (99.9%) inactivation took 9 hours at 60%. This suggests that enveloped viruses can survive on the surface of Tyvek suits for more than 6 hours, and should be considered a potential risk for contamination when they are taken off after use.

Human surrogates are representations of living humans, commonly adopted to better understand human response to impacts. Though surrogates have been widely used in automotive, defence and medical industries with varying levels of biofidelity, their primary application in the sporting goods industry has been through primitive rigid anvils used in assessing personal protective equipment (PPE) effectiveness. In sports, absence from competition is an important severity measure and soft tissue injuries such as contusions and lacerations are serious concerns. Consequently, impact surrogates for the sporting goods industry need a more subtle description of the relevant soft tissues to assess impact severity and mitigation accurately to indicate the likelihood of injury. The fundamental aim for this research study was to establish a method to enable the development of superior, complementary, increasingly complex synthetic and computational impact surrogates for improved assessment of sports personal protective equipment. With a particular focus on the thigh segment, research was conducted to evaluate incremental increases in surrogate complexity. Throughout this study, empirical assessment of synthetic surrogates and computational evaluation using finite element (FE) models were employed to further knowledge on design features influencing soft tissue surrogates in a cost and time efficient manner. To develop a more representative human impact surrogate, the tissue structures considered, geometries and materials were identified as key components influencing the mechanical response of surrogates. As a design tool, FE models were used to evaluate the changes in impact response elicited with different soft tissue layer configurations. The study showed the importance of skin, adipose, muscle and bone tissue structures and indicated up to 15.4% difference in maximum soft tissue displacement caused by failure to represent the skin layer. FE models were further used in this capacity in a shape evaluation study from which it was determined that a full-scale anatomically contoured thigh was necessary to show the full diversity of impact response phenomena exhibited. This was particularly pertinent in PPE evaluations where simple surrogate shapes significantly underestimated the magnitudes of displacements exhibited (up to 155% difference) when rigid shell PPE was simulated under impact conditions. Synthetic PDMS silicone simulants were then fabricated for each of the organic soft tissues to match their dynamic responses. The developed simulants exhibited a superior representation of the tissues when compared to previous single material soft tissue simulant, Silastic 3483, which showed 324%, 11,140% and -15.8% greater differences than the PDMS when compared to previously reported target organic tissue datasets for relaxed muscle, skin and adipose tissues respectively. The impact response of these PDMS surrogates were compared in FE models with previously used single material simulants in representative knee and cricket ball sports impact events. The models were each validated through experimental tests and the PDMS simulants were shown to exhibit significantly closer responses to organic tissue predictions across all impact conditions and evaluation metrics considered. An anatomically contoured synthetic thigh surrogate was fabricated using the PDMS soft tissue simulants through a novel multi-stage moulding process. The surrogate was experimentally tested under representative sports impact conditions and showed a good comparison with FE model predictions with a maximum difference in impactor displacements and peak accelerations of +6.86% and +12.5% respectively at velocities between 2 - 4 m.s-1. The value of increased biofidelity in the anatomical synthetic and virtual surrogate thighs has been proven through the incremental adoption of important surrogate elements (tissue structures, material and geometries). The predictive capabilities of each surrogate have been demonstrated through their parallel developments and staged comparisons with idealised organic tissue responses. This increase in biofidelity is introduced at modestly higher cost compared to Silastic 3483, but, given the benefits of a more representative human impact response for PPE evaluations, this is shown to be worthwhile.

Introduction: Preventing healthcare professionals from acquiring occupational infectious diseases is very important in maintaining healthcare delivery systems. For protection in the work place, healthcare professionals use PPE which helps prevent exposure to pathogens during patient care. N95 respirators protect healthcare workers against airborne pathogens that are known to be associated with different respiratory diseases. Since previous studies have shown that viruses can survive on PPE surfaces, it is important to examine the survival of viruses on respirators to determine if reuse of the same N95 respirator is possible when PPE shortages occur. Goal: The goal of this research is to determine the inactivation of bacteriophage Φ6 on the surface of N95 respirators at ambient temperature and two different relative humidity levels, 40 and 60%. Result: The linear regression showed that rate of inactivation was much lower in 40% than 60% RH (40%: Slope= -0.046± 0.007040; 60%: Slope= -0.20± 0.006136). Over 24 hours, there was a ~1 Log10 reduction in virus at 20°C and 40% RH, while there was a ~4 Log10 reduction at 20°C and 60% RH. Within the timeframe of a single patient encounter, there was a <0.02 Log10 reduction in virus at 40% RH and a <0.1 Log10 reduction at 60% RH. Conclusion: Bacteriophage Φ6 survives on N95 respirators for up to 24 hours at ambient temperature and 40 and 60% relative humidity levels. Inactivation rate was lower in 40% than 60% RH. The results showed that enveloped viruses survive on the surface of N95 respirators for longer than a single patient encounter. Therefore, this should be taken into consideration when doing a risk assessment of reusing N95 respirators when shortages occur.

The human body compensates well for moderate climatic heat stress, but artificial environments often block or overwhelm physiological defense mechanism. Personal protective equipment (PPE) is one of sources of heat stress. It protects individual from chemical, physical, or biological hazards, but the high thermal insulation and low vapor permeability of PPE may also lead to substantial heat stress. Personal cooling is widely used to alleviate heat stress, especially for those situations where ambient environmental cooling is not economically viable or feasible. It is important to predict the physiological responses of a person wearing PPE with personal cooling to make sure that the individual is free of heat stress, as well as any additional discomfort that may occur. Air temperature, radiant temperature, humidity and air movement are the four basic environmental parameters that affect human response to thermal environments. Combined with the personal parameters of metabolic heat generated by human activity and clothing worn by a person, they provide the six fundamental factors which define human thermal environments. If personal cooling system is available, the fluid flow speed, cooling tube distribution density and fluid inlet temperature have significant effects on the human thermal comfort. It is impractical to evaluate the problem experimentally due to too many factors involved. A thermal model was developed to improve human body thermal comfort prediction. The system researched includes human body, personal cooling system, clothing and environment. An existing model of thermoregulation is taken as a starting point. Changes and additions are made to provide better prediction. Personal cooling model was developed and it includes liquid cooling model, air cooling model and ice cooling model. Thermal resistance networks for the cooling system are built up; additionally a combined model of heat and mass transfer from cooling garment through clothing to environment is developed and incorporated into the personal cooling model and thermoregulatory model. The control volume method is employed to carry out the numerical calculation. An example simulation is presented for extra-vehicular activities on Mars. The simulation results agree well with available experimental data, though a small discrepancy between simulation results and experimental data is observed during the beginning of the cooling process. Compared with a water cooling lumped model, the thermal model provides a much better prediction. For water cooling, parametric study shows that the cooling water inlet temperature and liner thermal resistance have great effects on the maximum exposure time; PPE resistance and cooling water flow rate do not have much impact on the maximum exposure time. For air cooling, cooling air flow rate, inlet temperature, relative humidity and liner resistance have great effects on the maximum exposure time.

No description available.

No description available.