Effect of Protective Clothing and Fatigue on Functional Balance of Firefighters

We investigated the effects of wearing personal protective equipment (PPE), design of PPE (Standard vs.Enhanced), and fatigue during a simulated firefighting activity on the functional balance of firefighters. We defined functional balance as the ability to prevent a loss of balance and maintain body posture while performing functional tasks. A novel Functional Balance Test (FBT) was used to assess functional balance of firefighters while stepping up, stepping down, turning, walking along a beam, and passing under an obstacle. Data are presented from fifty-seven male firefighters, who were randomly divided into two groups: Standard PPE (n=28) and Enhanced PPE (n=29). The specially designed Enhanced PPE was lighter, more breathable, and capable of air circulation, compared to traditional Standard PPE. Each participant performed the FBT at three time periods (baseline with station uniform, pre-activity with PPE, and post-activity with PPE after a live-fire simulated firefighting activity). The firefighting activity involved alternating 2-minute rest- work cycles of four stations: stair climb, forcible entry, room search, and hose advancement. The FBT had four trials each with and without an overhead obstacle. Performance errors (major and minor), performance time, and a composite performance index were recorded. Wearing PPE significantly impaired functional balance, as noted by increases in all performance metrics. Following the firefighting activity, performance time increased by 3% but the number of minor and major errors decreased by 13% and 32%, respectively, suggesting that firefighters may trade-off between speed and accuracy depending on perceived threat to balance safety. There was no significant difference in functional balance between the Enhanced PPE and Standard PPE groups, suggesting that Enhanced PPE with a passive cooling system and an external circulating hose is not effective in improving functional balance of firefighters. A better designed PPE, with an improved cooling system and minimal (or no) protruding attachments may be of benefit in terms of firefighter functional balance.Ope

Effect of SCBA Design and Firefighting Induced Fatigue on Balance, Gait and Safety of Movement

Here we presented a report for the Fire Service documenting an examination of the effect of SCBA and firefighting induced fatigue on firefighters’ gait, balance, and safety of movement. More detailed, peer-reviewed scientific reports can be found in academic literature and are available at the Illinois Fire Service Institute. Fireground operations are inherently dangerous, with overexertion/ strain and slips, trips, and falls being the two leading causes of injury. 26.5% of fireground injuries are a result of overexertion or strain, conditions which may be accelerated by the fact that firefighting activities can induce near maximal heart rates and elevated core temperatures. The high levels of effort and exertion needed to complete such activities may be made worse by the firefighter’s turnout gear and self-contained breathing apparatus (SCBA). Anecdotal evidence suggests a trend in the Fire Service toward extended duration SCBA (greater than 30-min), which may further increase the physical demand on the firefighter. Further, nearly 23% of fireground injuries are the result of a slip, trip, and/or fall. These injuries often occur while or following firefighting activities, and may often be a result of the fatigue those activities have induced in the firefighter. Extended duration SCBA are typically heavier and may reduce the time before the firefighter becomes fatigued. Thirty firefighters were recruited to take part in repeated-measures study to examine the effects of SCBAs and duration of work cycle have on physiological strain, balance, gait, and safety of movement. Firefighters completed seven different conditions with various SCBA (30, 45, and 60-minute standard cylindrical SCBA and a low-profile 45-min prototype) and durations of simulated firefighting (one or two bouts) in a heated environmental chamber (117°F (47°C)). Four activities were performed (stair climb, hose advance, secondary search, and overhaul) on two-minute work-rest cycles. Subjects also completed an obstacle course designed to test their gait and functional balance prior to, and immediately after the simulated firefighting activities. Following firefighting activity firefighters had elevated heart rates and core temperatures. The firefighters also generally performed worse in the obstacle course. The size of the SCBA had a minimal impact on the firefighters, though it did decrease the performance on a Functional Balance Test. The low-profile prototype SCBA impacted the firefighters in a similar manner as the traditional cylindrical SCBA, though firefighters generally took longer to pass through a 16-inch on-center stud space. When firefighters completed multiple bouts of simulated firefighting activity heart rates and core temperatures were elevated relative to a single bout while the number of repetitions performed during each activity decreased. Performance during the obstacle course was also more negatively impacted following a second bout of activity than after a single bout.U.S. Department of Homeland Security through the Assistance to Firefighters Grant Program (Research and Development grant: EMW-2010-FP-01606)Ope

Physiological response to firefighting activities of various work cycles using extended duration and prototype SCBA

Firefighters’ self-contained breathing apparatus (SCBA) protects the respiratory system during firefighting but increases the physiological burden. Extended duration SCBA (>30 min) have increased air supply, potentially increasing the duration of firefighting work cycles. To examine the effects of SCBA configuration and work cycle (length and rest), 30 firefighters completed seven trials using different SCBA and one or two bouts of simulated firefighting following work cycles common in the United States. Heart rate, core temperature, oxygen consumption, work output and self-reported perceptions were recorded during all activities. Varying SCBA resulted in few differences in these parameters. However, during a second bout, work output significantly declined while heart rates and core temperatures were elevated relative to a single bout. Thirty seven per cent of the subjects were unable to complete the second bout in at least one of the two-bout conditions. These firefighters had lower fitness and higher body mass than those who completed all assigned tasks. Practitioner Summary: The effects of extended duration SCBA and work/rest cycles on physiological parameters and work output have not been examined. Cylinder size had minimal effects, but extended work cycles with no rest resulted in increased physiological strain and decreased work output. This effect was more pronounced in firefighters with lower fitness.This work was supported by the Department of Homeland Security Fire Prevention and Safety, Federal Emergency Management Agency [grant number EMW-2010-FP-01606].Ope

Nitric Oxide Releasing Materials Triggered by Near-Infrared Excitation Through Tissue Filters

Novel materials for the phototherapeutic release of the bioregulator nitric oxide (nitrogen monoxide) are described. Also reported is a method for scanning these materials with a focused NIR beam to induce photouncaging while minimizing damage from local heating. The new materials consist of poly(dimethylsiloxane) composites with near-infrared-to-visible upconverting nanoparticles (UCNPs) that are cast into a biocompatible polymer disk (PD). These PDs are then impregnated with the photochemical nitric oxide precursor Roussin's black salt (RBS) to give UCNP_RBS_PD devices that generate NO when irradiated with 980 nm light. When the UCNP_RBS_PD composites were irradiated with NIR light through filters composed of porcine tissue, physiologically relevant NO concentrations were released, thus demonstrating the potential of such devices for minimally invasive phototherapeutic applications

A Review of New Analytic Techniques for Quantifying Symmetry in Locomotion

We present a review of novel techniques developed by our research group to improve quantitative assessment of human movement, especially assessments related to symmetric and asymmetric gait patterns. These new methods use motion capture data of the lower limb joints (e.g., joint and body segment angular position and/or velocity, or joint center locations) and include: (1) Regions of Deviation (ROD) analysis, (2) complexity and variability of phase portraits, and (3) multivariate shape-alignment and decomposition. We provide example demonstrations of these techniques using data from infants, typical and atypically developing children, simulated injuries of a knee or ankle, and wheelchair propulsion