Bushfire Co Operative Research Center

Melbourne, Australia

Bushfire Co Operative Research Center

Melbourne, Australia
Time filter
Source Type

Raines J.,Deakin University | Raines J.,Bushfire Co Operative Research Center | Snow R.,Deakin University | Petersen A.,Deakin University | And 6 more authors.
Applied Ergonomics | Year: 2012

Wildfire fighters are known to report to work in a hypohydrated state, which may compromise their work performance and health. Purpose: To evaluate whether ingesting a bolus of fluid before the shift had any effect on firefighters' fluid consumption, core temperature, or the time they spent in high heart rate and work activity zones when fighting emergency wildfires. Methods: Thirty-two firefighters were divided into non-bolus (AD) and pre-shift drinking bolus (PS, 500ml water) groups. Results: Firefighters began work hypohydrated as indicated by urine colour, specific gravity and plasma osmolality (P osm) results. Post-shift, firefighters were classified as euhydrated according to P osm and hypohydrated by urinary markers. No significant differences existed between the drinking groups in pre- or post-shift hydration status, total fluid intake, activity, heart rate or core temperature. Conclusion: Consuming a bolus of fluid, pre-shift provided no benefit over non-consumption as both groups had consumed equivalent ad libitum volumes of fluid, 2.5h into the shift. No benefits of bolus consumption were observed in firefighter activity, heart rate response or core temperature response across the shift in the mild weather conditions experienced. Ad libitum drinking was adequate to facilitate rehydration in firefighters upon completion of their emergency firefighting work shift. © 2011 Elsevier Ltd and The Ergonomics Society.

Wolkow A.,Deakin University | Wolkow A.,Bushfire Co operative Research Center | Netto K.,Deakin University | Aisbett B.,Deakin University | Aisbett B.,Bushfire Co operative Research Center
International Archives of Occupational and Environmental Health | Year: 2013

Purpose: The physical demands and hazards associated with emergency service work place particular stress on responders' cardiovascular systems. Indeed, cardiovascular disease (CVD) is a significant problem for emergency service personnel. Although it may be difficult to alter the cardiovascular health hazards associated with the work environment, it is possible for personnel to control their modifiable CVD risk factors, cardiovascular fitness levels and subsequently, reduce their CVD risk. This review aimed to determine the effectiveness and methodological quality of health interventions designed to mitigate CVD risk in emergency service personnel. Methods: A literature search of electronic journal databases was performed. Sixteen relevant studies were assessed for methodological quality using a standardised assessment tool. Data regarding the effectiveness of each intervention were extracted and synthesised in a narrative format. Results: Fifteen studies were rated 'Weak' and one study was rated 'Strong'. Interventions which combined behavioural counselling, exercise and nutrition were more effective in improving cardiovascular health than nutrition, exercise or CVD risk factor assessment-based interventions alone. Further, CVD risk factor assessment in isolation proved to be an ineffective intervention type to reduce CVD risk. Conclusion: Combined interventions appear most effective in improving the cardiovascular health of emergency service personnel. Accordingly, fire and emergency service agencies should consider trialling multifaceted interventions to improve the cardiovascular health of personnel and avoid interventions focused only on one of nutrition, exercise or CVD risk factor assessment. However, as most studies were methodologically weak, further studies of a higher methodological quality are needed. © 2013 Springer-Verlag Berlin Heidelberg.

O'Donnell A.J.,University of Western Australia | Cullen L.E.,University of Western Australia | Lachlan McCaw W.,Brain Street | Lachlan McCaw W.,Bushfire Co operative Research Center | And 4 more authors.
Dendrochronologia | Year: 2010

Historical fire regimes in the semi-arid shrublands of southern Western Australia are poorly understood, largely owing to a lack of quantitative historical data. We sought to determine the dendroecological potential of fire-sensitive Callitris preissii Miq. trees to date historical fires and extend the length of fire-history data available from remotely sensed imagery. We sampled C. preissii trees from known fire areas in the Lake Johnston region in southern Western Australia. Our objective was to assess the capacity to date historical fires using stand establishment date as a proxy measure of time since fire. We measured stem basal diameter and height and collected stem sections of C. preissii trees and saplings from five areas that were burnt on known dates between 1974 and 2001. We also sampled older trees (>35 years), which were used to create a master chronology to assist with dating of seedlings and saplings. Tree age could not be reliably estimated from stem basal diameter and tree height, with 95% prediction intervals of more than 17 years. However, we were able to successfully determine tree age and develop a ring-width chronology using standard dendrochronological techniques. The cross-dated chronology showed a relatively high inter-series correlation in ring width (r=0.63) indicating consistency in growth rate among samples and sites, while mean sensitivity (0.39) signified high inter-annual variability in ring width. The age structure of C. preissii stands revealed consistent recruitment within 1 year of fire occurrence and maximum intra-stand variation in tree age of 4 years. Our results confirm that C. preissii has significant dendroecological potential to accurately date past fire events and that this approach will assist in extending fire-history records beyond recent decades for much of southern semi-arid Australia. © 2009 Elsevier GmbH.

Raines J.,Deakin University | Raines J.,Bushfire Co Operative Research Center | Snow R.,Deakin University | Nichols D.,Bushfire Co Operative Research Center | And 3 more authors.
Annals of Occupational Hygiene | Year: 2015

Purpose: (i) To evaluate firefighters' pre-And post-shift hydration status across two shifts of wildfire suppression work in hot weather conditions. (ii) To document firefighters' fluid intake during and between two shifts of wildfire suppression work. (iii) To compare firefighters' heart rate, activity, rating of perceived exertion (RPE), and core temperature across the two consecutive shifts of wildfire suppression work. Method: Across two consecutive days, 12 salaried firefighters' hydration status was measured immediately pre-And post-shift. Hydration status was also measured 2 h post-shift. RPE was also measured immediately post-shift on each day. Work activity, heart rate, and core temperature were logged continuously during each shift. Ten firefighters also manually recorded their food and fluid intake before, during, and after both fireground shifts. Results: Firefighters were not euhydrated at all measurement points on Day one (292 } 1 mOsm l1) and euhydrated across these same time points on Day two (289 } 0.5 mOsm l1). Fluid consumption following firefighters' shift on Day one (1792 } 1134 ml) trended (P = 0.08) higher than Day two (1108 } 1142 ml). Daily total fluid intake was not different (P = 0.27), averaging 6443 } 1941 ml across both days. Core temperature and the time spent 70%HRmax were both elevated on Day one (when firefighters were not euhydrated). Firefighters' work activity profile was not different between both days of work. Conclusion: There was no difference in firefighters' pre-to post-shift hydration within each shift, suggesting ad libitum drinking was at least sufficient to maintain pre-shift hydration status, even in hot conditions. Firefighters' relative hypohydration on Day one (despite a slightly lower ambient temperature) may have been associated with elevations in core temperature, more time in the higher heart rate zones, and 'post-shift' RPE. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

O'Donnell A.J.,University of Western Australia | O'Donnell A.J.,Bushfire Co operative Research Center | Boer M.M.,University of Western Australia | Boer M.M.,Bushfire Co operative Research Center | And 4 more authors.
Ecosphere | Year: 2014

Variation in the frequency, extent and intensity of wildfires can drive changes in the composition, structure, diversity and functioning of ecosystems in fire-prone regions worldwide. However, relationships between climatic variation and wildfire occurrence remain poorly understood in many fireprone regions. We investigated fire occurrence and extent across 15,500 km2 of semi-arid southwest Australia in relation to inter-annual and/or seasonal variation in regional climate and broad-scale circulation patterns. Superposed epoch analysis (SEA) was used to determine whether wildfire occurrence was related to anomalously high or low regional rainfall or temperature. In particular, we tested if years of minor fire extent (i.e., <250 km2 burnt) and major fire extent (i.e., >1,000 km2 burnt) occurred under different climatic conditions. We also used SEA to determine if wildfires occurred during or following periods of extremes of drivers of regional climate, including the El Niño southern oscillation (ENSO), the Indian Ocean dipole, atmospheric blocking in the adjacent Southern Ocean, and the southern annular mode (SAM). Fire occurrence was linked to dry and hot conditions typically associated with the El Niño phase of ENSO, with few or no fires in years with cool and wet summers. However, major fire years tended to occur during drought conditions that followed wet and cool conditions in spring and summer of the preceding year. These wet and cool periods were typically associated with the presence of blocking highs in the Southern Ocean to the south of Western Australia. We hypothesise that high rainfall in spring and summer favours the growth of ephemeral plants while subsequent drought conditions promote fuel drying, resulting in more continuous and highly flammable fuel beds capable of sustaining larger fires. Regional climatic patterns are likely driven by interactions among the SAM, atmospheric blocking, and decaying tropical cyclones. As climatic extremes are expected to increase in intensity and frequency in the future, it is likely that the occurrence of extensive wildfires in semi-arid southwest Australia will also increase, potentially driving changes in the distribution and composition of fire-sensitive plant communities. Copyright: © 2011 O'Donnell et al.

Fox-Hughes P.,University of Tasmania | Fox-Hughes P.,Bushfire Co operative Research Center
Journal of Applied Meteorology and Climatology | Year: 2011

Half-hourly airport weather observations have been used to construct high-temporal-resolution datasets of McArthur Mark V forest fire danger index (FFDI) values for three locations in Tasmania, Australia, enabling a more complete understanding of the range and diurnal variability of fire weather. Such an understanding is important for fire management and planning to account for the possibility of weather-related fire flare ups-in particular, early in a day and during rapidly changing situations. In addition, climate studies have hitherto generally been able to access only daily or at best 3-hourly weather data to generate fire-weather index values. Comparison of FFDI values calculated from frequent (subhourly) observations with those derived from 3-hourly synoptic observations suggests that large numbers of significant fire-weather events are missed, even by a synoptic observation schedule, and, in particular, by observations made at 1500 LT only, suggesting that many climate studies may underestimate the frequencies of occurrence of fire-weather events. At Hobart, in southeastern Tasmania, only one-half of diurnal FFDI peaks over a critical warning level occur at 1500 LT, with the remainder occurring across a broad range of times. The study reinforces a perception of pronounced differences in the character of fire weather across Tasmania, with differences in diurnal patterns of variability evident between locations, in addition to well-known differences in the ranges of peak values observed. © 2011 American Meteorological Society.

PubMed | Bushfire Co Operative Research Center and Deakin University
Type: Journal Article | Journal: International archives of occupational and environmental health | Year: 2016

Physical work and sleep restriction are two stressors faced by firefighters, yet the combined impact these demands have on firefighters acute stress responses is poorly understood. The purpose of the present study was to assess the effect firefighting work and sleep restriction have on firefighters acute cortisol and heart rate (HR) responses during a simulated 3-day and 2-night fire-ground deployment.Firefighters completed multiple days of simulated physical work separated by either an 8-h (control condition; n = 18) or 4-h sleep opportunity (sleep restriction condition; n = 17). Salivary cortisol was sampled every 2 h, and HR was measured continuously each day.On day 2 and day 3 of the deployment, the sleep restriction condition exhibited a significantly higher daily area under the curve cortisol level and an elevated cortisol profile in the afternoon and evening when compared with the control condition. Firefighters HR decreased across the simulation, but there were no significant differences found between conditions.Findings highlight the protective role an 8-h sleep opportunity between shifts of firefighting work has on preserving normal cortisol levels when compared to a 4-h sleep opportunity which resulted in elevated afternoon and evening cortisol. Given the adverse health outcomes associated with chronically high cortisol, especially later in the day, future research should examine how prolonged exposure to firefighting work (including restricted sleep) affects firefighters cortisol levels long term. Furthermore, monitoring cortisol levels post-deployment will determine the minimum recovery time firefighters need to safely return to the fire-ground.

Kruger T.M.,University of Melbourne | Kruger T.M.,Bushfire Co operative Research Center | Beilin R.,University of Melbourne
International Journal of Wildland Fire | Year: 2014

This research considers ideas about local knowledge and place for firefighters during a bushfire. In 2012, we interviewed 68 Australian bushfire firefighters from selected agencies and volunteer brigades in diverse localities. The findings from the interviews indicate local knowledge can help firefighters to navigate tracks and understand fire behaviour in familiar landscapes. At the same time, they can experience a heightened awareness of the fire on local people and valued assets. This sets up a 'responsibility for place', which can both mediate actions during the fire and increase risk to the firefighters involved. A distant fire can present many unknowns and potential hazards for deployed firefighters because they do not have local knowledge. This disconnect can mean they are more cautious in negotiating unfamiliar surrounds and awaiting orders. We find that although local knowledge can assist firefighters, it highlights the complexity of decision-making during a fire that can make it more hazardous for local firefighters. This research contributes to firefighter training by exploring how local knowledge associated with landscape and community can dominate decision-making in practice. © IAWF 2014.

PubMed | Bushfire Co Operative Research Center and Deakin University
Type: Journal Article | Journal: International journal of occupational medicine and environmental health | Year: 2015

Emergency work can expose personnel to sleep restriction. Inadequate amounts of sleep can negatively affect physiological and psychological stress responses. This review critiqued the emergency service literature (e.g., firefighting, police/law enforcement, defense forces, ambulance/paramedic personnel) that has investigated the effect of sleep restriction on hormonal, inflammatory and psychological responses. Furthermore, it investigated if a psycho-physiological approach can help contextualize the significance of such responses to assist emergency service agencies monitor the health of their personnel. The available literature suggests that sleep restriction across multiple work days can disrupt cytokine and cortisol levels, deteriorate mood and elicit simultaneous physiological and psychological responses. However, research concerning the interaction between such responses is limited and inconclusive. Therefore, it is unknown if a psycho-physiological relationship exists and as a result, it is currently not feasible for agencies to monitor sleep restriction related stress based on psycho- physiological interactions. Sleep restriction does however, appear to be a major stressor contributing to physiological and psychological responses and thus, warrants further investigation.

PubMed | Bushfire Co Operative Research Center and Deakin University
Type: Journal Article | Journal: Applied psychophysiology and biofeedback | Year: 2016

This study examined how changes in wildland firefighters mood relate to cytokine and cortisol levels in response to simulated physical firefighting work and sleep restriction. Firefighters completed 3days of simulated wildfire suppression work separated by an 8-h (control condition; n=18) or 4-h sleep opportunity (sleep restriction condition; n=17) each night. Firefighters mood was assessed daily using the Mood Scale II and Samn-Perelli fatigue scale. Participants also provided samples for the determination of salivary cortisol and pro- (IL-6, IL-8, IL-1, TNF-) and anti-inflammatory (IL-4, IL-10) cytokine levels. An increase in the positive mood dimension Happiness was related to a rise in IL-8 and TNF- in the sleep restriction condition. A rise in the positive mood dimension Activation among sleep restricted firefighters was also related to higher IL-6 levels. An increase in the negative mood dimension Fatigue in the sleep restriction condition was associated with increased IL-6, TNF-, IL-10 and cortisol levels. In addition, an increase in Fear among sleep restricted firefighters was associated with a rise in TNF-. Elevated positive mood and immune activation may reflect an appropriate response by the firefighters to these stressors. To further understand this relationship, subsequent firefighting-based research is needed that investigates whether immune changes are a function of affective arousal linked to the expression of positive moods. Positive associations between negative mood and inflammatory and cortisol levels to physical work and restricted sleep provide useful information to fire agencies about subjective fire-ground indicators of physiological changes.

Loading Bushfire Co Operative Research Center collaborators
Loading Bushfire Co Operative Research Center collaborators