Prescriptive fire safety codes regulate the use of combustible room linings to reduce fire risk. These regulations are based on classification systems which designate materials according to their relative hazard when exposed to a standard fire scenario. However, no quantitative data sets on the fire risk of wooden lining materials exist which take into account relevant uncertainties, such as movable fuel loads in compartments. This work is a comparative risk analysis on the influence of wooden linings on the time to flashover in a compartment, considering uncertainties in the fuel load configuration. A risk model is set up for this purpose using B-RISK, a probabilistic fire design and research tool currently under development at BRANZ (Building Research Association of New Zealand) and the University of Canterbury. The risk model calculates fire spread in a compartment between fuel load items and from fuel load items to combustible linings. Multiple iterations are performed considering varying fuel load arrangements and input values sampled from distributions (Monte-Carlo simulation). The functionality and applicability of the risk model is demonstrated, comparing the model with experiments from the literature. The model assumptions are described in detail. Some of the model inputs are defined as distributions in order to account for uncertainty. Parametric studies are conducted in order to analyse the sensitivity of the results to input parameters which cannot be described as distributions. Probabilistic times to flashover are presented and discussed for an ISO 9705 compartment considering varying movable fuel loads and different lining configurations. The fuel load is typical for a hotel room occupancy. Effects of suppression measures are not considered. It is shown that flashover occurs approximately 60 seconds earlier if walls and ceiling are lined with wooden materials than if all linings are non-combustible. This value refers to the 5th percentiles of the time to flashover, i.e. in 5% of the cases flashover has occurred and in 95% of the cases flashover has not (yet) occurred. Referring to 50th percentiles (median values), the difference is approximately 180 seconds. Furthermore it is shown that with wooden wall and ceiling linings in approximately 95% of the iterations flashover occurs, whereas with non-combustible linings 86% of the iterations lead to flashover. After 900 seconds, in 90% of the iterations flashover occurs if walls and ceiling are lined with wooden materials, and in 77% of the iterations if the linings are non-combustible. Using different wooden lining materials (non-fire retardant plywood, fire retardant plywood, and MDF) has no significant effect on the probabilistic times to flashover. Varying the fuel load energy density has an influence only when all linings are non-combustible and when the fuel load energy density is relatively low (100–200 MJ/m2). This work contains recommendations regarding the further development of B-RISK, the research into the fire risk connected with wooden room linings, and suggestions regarding the further development of prescriptive fire safety codes.

At a state university in the Pacific Northwest, the authors surveyed 477 matriculating college students about their immunization status, knowledge, self-perceived risk, and health risk behaviors for hepatitis A and B vaccinations. Review of immunization records revealed that 10% of these students were completely immunized for hepatitis A and 58.8% were completely immunized for hepatitis B. Although their knowledge about hepatitis A and B was very good, there were no significant differences in immunization status or health risk behaviors based on their knowledge or their self-perceived risk of hepatitis A and B. About 66% of students perceived they had no risk or low risk for hepatitis A and B and only 5% felt they had a high risk. In spite of the low self-perceived risk, health risk behaviors for hepatitis A and B were common in this population of college students. In the past twelve months, 56.2% of these students reported being sexually active (vaginal, oral, anal sex), including 20.5% who had two or more sexual partners. Students with multiple sexual partners reported having unprotected sex at a high frequency: 61.3% vaginal, 81.1% oral-genital, and 13.2% anal. The non-sexual health risk behaviors were also common in this population: 53.2% had body piercing/tattoos, and 26.5% traveled internationally to regions with intermediate to high rates of hepatitis A (Africa, SE Asia, Central/South America). These students who traveled internationally were more likely to be immunized for hepatitis A, although 70% remained unimmunized. In addition, students with multiple sexual partners or with a body piercing/tattoo were more likely to be immunized for hepatitis B. However, about one-third of these students with multiple sexual partners or body piercing/tattoo have not completed the hepatitis B series. The theory of planned behavior was applied to determine factors that are associated with college students' decision to be vaccinated for hepatitis A and B. For hepatitis A and B vaccinations, important attitude constructs identified were 'vaccine effectiveness, vaccine adverse effects, anticipation anxiety, inconvenience, and vaccine expense.' The subjective norm constructs with the greatest influence for college students were: 'parents, family doctor, and student health services staff'. The significant perceived behavioral constructs were 'parents reminder, student health services (SHS) reminder, and SHS hepatitis vaccine clinic.' In conclusion, there is still a sizable portion of unvaccinated college students who possess health risk behaviors for hepatitis A and B, such as multiple sexual partners, unprotected sexual behaviors, body piercing/tattoos, and international travel. With a greater understanding of college students' attitudes, subjective norms, and perceived behavioral control college health services could develop more effective strategies to educate unvaccinated college students about these risks and motivate them to be immunized. / Graduation date: 2003