Fall Hazard Research Articles

Preliminary approach for prioritizing resource allocation for rock fall hazard investigations based on susceptibility mapping and efficient three-dimensional trajectory modelling

Rock fall hazard management typically requires efficient allocation of available resources for detailed hazard assessment and control. In mountainous terrain, remoteness and difficult access pose a challenge for resource allocation decision-making. In this paper, we evaluate a systematic approach for decision-making based on topographic susceptibility and efficient three-dimensional trajectory modelling. The approach relies on the availability of detailed digital elevation models, a strategy which is now considered to be the state of practice. In this study, it is assumed that geologic and rock mass quality information, as well as rock fall occurrence records, are not available in the necessary detail across the area of study for them to be used in rock fall hazard assessments. The approach is illustrated with a case study along a section of railway within the Canadian Cordillera. The advantages and limitations of the approach are discussed, as well as some key considerations for its application.

The Integration of ASRC System within BIM

Technically, safety planning and project execution planning has been carried out separately for most BIM-based projects. As such, it leads to difficulties in monitor these planning simultaneously during construction phase. In this regards, the Automated Safety Rule Checking (ASRC) system is perceived to distinguish fall hazards by integrating the system in the existing BIM-model. This paper pursues to explore the integration of ASRC system within BIM-based projects in Malaysia. A cross-sectional survey was employed to large public and private organisations that involved with BIM. The data were analysed by using content analysis technique and revealed that ASRC system is yet to be incorporated into BIM-based projects in Malaysia.

Evaluating relative tephra fall hazard and risk in the Asia-Pacific region

Evaluating relative tephra fall hazard and risk in the Asia-Pacific region

Identifying locations along railway networks with the highest tree fall hazard

Disruptions of railway traffic have many reasons. Tree falls onto railway tracks or overhead lines rank among the most common causes of disruptions of a natural origin. 2039 tree-fall events, containing up to 70 individual trees per event, were registered on the Czech railway network between 2012 and 2015. 32% of them were directly caused by 14 weather extremes during which more than 20 concurrent tree-fall events were registered. Moreover, 12 train derailments due to fallen trees were registered on Czech railways within the same period.We combined land use data along railway tracks and data on tree falls. Land use and railway tracks data were obtained from a freely available Open Street Map database. The tree fall hazard was then computed using empirical data, data on land use and a generalized rule of succession. The clustering approach was also applied to focus on localities where tree falls were concentrated regardless of the resulting segment hazard. There were 59 rail track segments (out of 2960) with the highest tree fall hazard and 267 clusters were finally identified. The clusters and the most hazardous railway segments will be among the first in the process of line side vegetation monitoring in order to minimize potential losses from tree fall. The presented method can be widely applicable elsewhere.

Evaluating the stability of a freestanding Mast Climbing Work Platform

Mast Climbing Work Platforms (MCWPs) are becoming more common at construction sites and are being used as an alternative to traditional scaffolding. Although their use is increasing, little to no published information exists on the potential safety hazards they could pose for workers. As a last line of defense, a personal fall-arrest system can be used to save a worker in a fall incident from the platform. There has been no published information on whether it is safe to use such a personal fall-arrest system with MCWPs. In this study, the issues of concern for occupational safety included: (a) the overall stability of the freestanding mast climber during a fall-arrest condition and (b) whether that fall-arrest system could potentially present safety hazards to other workers on the platform during a fall-arrest condition. This research project investigated those safety concerns with respect to the mast climber stability and the workers using it by creating fall-arrest impact forces that are transmitted to the equipment and by subsequently observing the movement of the mast climber and the working deck used by the workers. This study found that when the equipment was erected and used according to the manufacturer's recommendations during a fall-arrest condition, destabilizing forces were very small and there were no signs of potential of MCWP collapse. However, potential fall hazards could be presented to other workers on the platform during a fall arrest. Workers near an open platform are advised to wear a personal fall-arrest system to reduce the risk of being ejected. Due to the increasing use of MCWPs at construction sites, there is a corresponding need for evidence and science-based safety guidelines or regulations and further research should be conducted to continue to fill the knowledge gap with MCWP equipment.

Quantifying rock fall probabilities and their temporal distribution associated with weather seasonality

Quantifying rock fall hazards requires information about their frequency and volumes. Previous studies have focused on quantifying rock fall volume–frequency relationships or the weather conditions antecedent to rock fall occurrences, and their potential use as prediction tools. This paper is focused on quantifying rock fall occurrence probabilities and presents approaches for quantifying rock fall temporal distributions. In particular, von Mises distributions allow direct correlation between seasonal weather variations and rock fall occurrences. The approaches are illustrated using a rock fall database along a railway corridor in the Canadian Cordillera, in which rock fall occurrences were correlated to the morphology and lithology. A Binomial probability distribution applied to the annual rock fall frequency suggests an average daily rock fall probability of 1 × 10−2 across the study area. However, circular (von Mises) distributions associated with weather trends in the area, and fitted to monthly rock fall records, allow estimation of daily rock fall probabilities in different months. This approach allows a direct correlation between rock fall frequencies and seasonal variations in weather conditions. The results suggest daily rock fall probabilities between 4 × 10−3 and 8 × 10−3 for April through July and up to 2.1 × 10−2 in October. Moreover, local peaks in rock fall monthly records are quantitatively explained through the seasonality of weather conditions. Similar values are obtained when applying the Binomial distribution to monthly records. However, this last approach does not show strong distribution fits and does not allow a correlation between rock fall frequencies and seasonal weather variations.

Treadmill-based Perturbation Training For Preventing Falls Among Young Adults

Falls present a serious challenge not only among older adults, but for young adults, especially those whose working condition exposes them to a high fall hazard. Treadmill-based perturbation training, as a task-specific training, has emerged as a new paradigm used to prevent falls. However, the training program contained up to 30 perturbation trials in previous studies. It is unclear if a reduced number of perturbation trials could still induce positive effect in preventing falls. PURPOSE: To investigate the effect of a treadmill-based perturbation training paradigm consisting of 8 slip perturbations on reducing slip-related falls in young adults. METHODS: Thirteen healthy young adults (24 ± 4.34 years) were randomly assigned into either training (n = 6) or control (n = 7) groups. The training group underwent 8 unexpected slip trials on a special treadmill during gait while the control group received a “mock” training in which they walked on the same treadmill. After the training, both groups were subjected to an unexpected slip induced by releasing a movable platform when walking overground (OG). Subjects wore a safety harness equipped with a load cell. Body kinematics were captured and used to calculate dynamic gait stability on the OG slip. The load cell force was used to determine the OG slip outcome (fall vs. no-fall). A Chi-square test and independent t-test were used to respectively compare the fall incidents and dynamic stability between groups. RESULTS: Responding to the OG slip, 4 out of 7 (57.1%) subjects in the control group while 1 out of 6 (16.7%, p = 0.18) in the training group fell. The training group displayed a lower instability than the control at recovery foot touchdown (-0.56 ± 0.12 vs. -0.69 ± 0.07, p < 0.05). CONCLUSIONS: This study suggests that treadmill-based perturbation training with less perturbation trials could lower the risk of falls among young adults when exposed to a real-life like OG slip. Given that treadmill-based slip training is easy to use, portable, controllable, and reproducible, this training could provide a relatively novel modality to reduce falls among both young and older adults. Further studies based on a large sample size are needed to symmetrically evaluate the effectiveness of this type of training. Supported by the PiMSA Graduate Student Grant.

Collective sensing of workers' gait patterns to identify fall hazards in construction

Abstract Current hazard-identification efforts in construction mostly rely on human judgment, a reality that leaves a significant number of hazards unidentified or not well-assessed. This situation highlights a need for enhancing hazard-identification capabilities in dynamic and unpredictable construction environments. Given the fact that hazards cause disruptions in workers' behaviors and responses, capturing such disruptions offers opportunities for identifying hazards. This study proposes a collective sensing approach that senses and assesses workers' gait abnormalities in order to identify physical fall hazards in a construction jobsite. Laboratory experiments simulating an ironworkers' working environment were designed and conducted to examine the feasibility of the proposed approach. A wearable inertial measurement unit (WIMU) attached to a subject's ankle collected kinematic gait data. The results indicated that the aggregated gait abnormality score from multiple subjects have a strong correlation with the existence of installed fall hazards such as obstacles and slippery surfaces. This outcome highlights the opportunity for future devices to use workers' abnormal gait responses to reveal safety hazards in construction environments.

Rock fall hazard control along a section of railway based on quantified risk

ABSTRACTRock falls represent a large percentage of landslide-related hazards reported by Canadian railways in mountainous terrain. A 54.7 km-long section of railway through the Canadian Cordillera is examined that experiences, on average, 18 rock falls each year. An approach for rock fall hazard management is developed based on quantified risk. The approach focuses on defining railway operation procedures (freight train operations and track maintenance) that comply with quantified risks. Weather-based criteria that define periods when rock falls are more likely to occur along the study area are examined. These criteria are used herein to reduce exposure to rock falls and reduce their consequences. Several freight train operation strategies are proposed that comply with a tolerable level of risk adopted in this study for illustrative purposes. The approach provides a simple, flexible and practical strategy for railway operations that can be regularly adopted by the operators, and that is based on a more comprehensive assessment of quantified risk.

Falling while walking: A hidden contributor to pedestrian injury

Walking is a sustainable mode of transportation which is beneficial to both individuals and to the broader community, however, there are risks and it is essential that road design and operation provides safe conditions for walking. In Victoria, pedestrians represent one of the most vulnerable road user groups, accounting for approximately 12% of all road fatalities and serious injuries. These figures largely represent injuries where the pedestrian has been struck by a vehicle with the extent of pedestrian-only injuries largely un-reported.Falling while walking may be a significant contributor to pedestrian only injuries. Indeed, the World Health Organisation has identified falls generally as the second leading cause of unintentional injury death in older populations. Despite the prevalence of fall-related injuries, there has been relatively little research undertaken to address the issues surrounding falls that occur while walking for transport and in public spaces. This study, therefore, aimed to address this gap in our knowledge.Analyses of various data sources were undertaken to enhance our understanding of fall-related injuries while walking in Victoria. Two sources of data were accessed:•Hospital data: Victorian Injury Surveillance Unit (VISU) Data (5-years between 2009 and 2014)•Crash data: Victorian Police Report Crash Data (Crash Stats) (5 years between 2008 and 2013)Only 85 fall-related incidents were reported in the crash-based data, however, pedestrian falls while walking in the road environment accounted for an average of 1680 hospital admissions and 3545 emergency department presentations each year, and this number is rising.The findings in this study show clearly that Police data is of little use when attempting to understand issues of safe travel for pedestrians other than vehicle-pedestrian incidents. However, analysis of hospital data provides a more realistic indication of the extent of pedestrian fall-related injuries and highlights the significant number of pedestrian fall-related injuries that occur each year. Moreover, the findings identified that older pedestrians are significantly over-represented amongst fall-related injuries that require hospital admission, while also having the highest rate of emergency department presentations when adjusting for age and exposure based on estimates of aggregate walking distances. The study also highlighted that the most common injury sustained from a fall were fractures.The implications of these findings and identification of ‘best-practice’ within a Safe System context are discussed in terms of enhancements to the physical environment (particularly footpath, kerb and ramp construction and maintenance), implementation of fall hazard assessment and management strategies, and educational programs to highlight the risks for falls and recommend preventative strategies, and overall enhancements of general fall interventions to include falls while walking outside (including exercise interventions). In addition, a number of research and data needs, particularly collection of in-depth data to identify contributory factors and injury outcomes related to falls while walking incidents.

EVALUATING THE TRIGGERING FACTORS OF THE ROCK FALLS OF 16TH AND 21ST DECEMBER 2009 IN NEA FOKEA, CHALKIDIKI, NORTHERN GREECE

This paper aims to present the characteristics of the rock falls generated on the 16th and 21st of December 2009 at the Nea Moudania – Kassandria country road in Kassandra Peninsula, Chalkidiki, Greece. Both of those events induced damages to the asphalt road and forced the local authorities to close the road to traffic until the construction of protective measures. In order to evaluate the rock fall hazard and analyze the slope instability in the area, the present study focuses on three main triggering factors: rainfall, stratigraphy and tectonic setting.

PRELIMINARY RESULTS REGARDING THE ROCK FALLS OF DECEMBER 17, 2009 AT TEMPI, GREECE

On December 17, 2009, a large size rock fall generated at the area of Tempi, Central Greece causing one casualty. In particular, a large block was detached from a high of 70 meters and started to roll downslope and gradually became a rock slide. About 120 tones of rock material moved downward to the road resulting to the close of the national road. Few days after the slope failure, a field survey organized by the Department of Geology, AUTH took place in order to evaluate the rock fall hazard in the area and to define the triggering causal factors. As an outcome, we concluded that the heavily broken rock mass and the heavy rain-falls, of the previous days, contribute significantly to the generation of the slope failure. The rocky slope was limited stable and the high joint water pressure caused the failure of the slope.

Hoverboards: spectrum of injury and association with an uncommon fracture.

Self-balancing electric scooters, commonly known as hoverboards, are a new and popular consumer item with recognized fall hazards. The spectrum of injuries associated with hoverboard use has not been studied. The purpose of this study is to determine the spectrum of radiologically apparent injuries associated with hoverboard use. We retrospectively reviewed all imaging studies interpreted at our institution for hoverboard-related injuries during an 8-month period. We recorded patient demographics and injury characteristics. Thirty-two of the 47 pediatric patients imaged for hoverboard-related injury had radiologically detectable injuries, all fractures. Fifty percent of these 32 patients were female and 50% were male, with a mean age of 12.4years. There were 42 fractures total, all involving the appendicular skeleton, with 74% in the upper extremities and 26% in the lower extremities. Thirty-eight percent of the fractures involved the physis. A distinct injury pattern was seen in three patients who sustained open distal phalanx juxta-epiphyseal fractures. Most of the fractures sustained during hoverboard use are commonly seen in everyday pediatric radiology practice, with an overall pattern paralleling that reported in association with skateboard use. However an otherwise uncommon fracture, the distal phalanx juxta-epiphyseal fracture, was identified in association with hoverboard use, and this finding has important treatment implications including need for irrigation and debridement, antibiotic therapy, and potential surgical fixation.

Theory and calibration of the Pierre 2 stochastic rock fall dynamics simulation program

The use of computer models to determine rock fall hazards is increasingly common, with increasingly complex models being developed. In most practical applications, slopes potentially affected by rock falls are characterized in general terms only, thus a simpler model is desirable to reduce the parameter uncertainty. The model presented here utilizes a lumped-mass representation of the rocks. Key features are the stochastic roughness angle to represent contact geometry variability, hyperbolic restitution factors, and a stochastic shape factor, which have been developed considering impact mechanics theory. Together, these features can yield realistic results for linear and angular velocity, bounce height, runout distance, and normal restitution factors greater than one while still being easy to calibrate. The model calibration has been carried out using detailed, full-scale experiments from a talus slope in France, a hard rock quarry in Austria, and a weak bedrock and talus slope in Japan. An observed rock fall event in British Columbia was modeled as a pseudoforward analysis to demonstrate the model validity. The usefulness of the model as a design tool has been demonstrated by using the simulation results as inputs for a hypothetical barrier design application, and calculating the reliability of the design values.

Quantifying Fall-Related Hazards in the Homes of Persons with Glaucoma

To characterize fall-related hazards in the homes of persons with suspected or diagnosed glaucoma, and to determine whether those with worse visual field (VF) damage have fewer home hazards. Cross-sectional study using baseline (2013-2015) data from the ongoing Falls in Glaucoma Study (FIGS). One-hundred seventy-four of 245 (71.0%) FIGS participants agreeing to the home assessment. Participants' homes were assessed using the Home Environment Assessment for the Visually Impaired (HEAVI). A single evaluator assessed up to 127 potential hazards in 8 home regions. In the clinic, binocular contrast sensitivity (CS) and better-eye visual acuity (VA) were evaluated, and 24-2 VFs were obtained to calculate average integrated VF (IVF) sensitivity. Total number of home hazards. No significant visual or demographic differences were noted between participants who did and did not complete the home assessment (P > 0.09 for all measures). Mean age among those completing the home assessment (n= 174) was 71.1 years, and IVF sensitivity ranged from 5.6 to 33.4 dB (mean= 27.2 dB, standard deviation [SD]= 4.0 dB). The mean number of items graded per home was 85.2 (SD= 13.2), and an average of 32.7 (38.3%) were identified as hazards. IVF sensitivity, CS, and VA were not associated with total home hazards or the number of hazards in any given room (P > 0.06 for all visual measures and rooms). The bathroom contained the greatest number of hazards (mean= 7.9; 54.2% of graded items classified as hazardous), and the most common hazards identified in at least 1 room were ambient lighting <300 lux and exposed light bulbs. Only 27.9% of graded rooms had adequate lighting. IVF sensitivity, CS, and VA were not associated with home lighting levels (P > 0.18 for all), but brighter room lighting was noted in the homes of participants with higher median income (P < 0.001). Multiple home fall hazards were identified in the study population, and hazard numbers were not lower for persons with worse VF damage, suggesting that individuals with more advanced glaucoma do not adapt their homes for safety. Further work should investigate whether addressing home hazards is an effective intervention for preventing falls in this high-risk group.

Designing a Snow-removing Tool Through Ergonomic Approach

Objective: The purpose of this study is to design a snow-removing tool using an ergonomic approach.BR Background: It is necessary to remove snow on the garden of a house or side street to prevent a fall hazard. When a user removes snow using a snow-removing tool, he or she experiences lots of physical discomfort. Therefore it is necessary to design a snow-removing tool to reduce a user

Development of a Slip Hazard: Partially Wetted Floors and Film Formation

Abstract Slip and fall hazards on wetted surfaces represent a substantial safety concern both in the home and workplace. In the presence of liquid contaminants, the hazards associated with potential slip and fall accidents are greatly increased. However, it is unclear at what point a partially wetted floor transitions from being a slip-resistant surface to a slip hazard. The presented work examines the relationship between film formation and slip hazards on flooring surfaces. First, a theoretical model was developed to predict the approximate onset of film formation for liquid droplets deposited uniformly across a surface. Then, the slip hazard of wetted flooring samples at various liquid contaminant surface densities was determined using a British Pendulum skid tester and an English XL tribometer. These experimental results were then compared with the theoretical model in an effort to further understand the role film formation plays in forming slip hazards on partially wetted floors. Using the combined approach, the minimum surface density loading required for a potential slip and fall hazard on a partially wetted surface was determined. This threshold value can inform safety professions of the potential injury risk of floors as they transition between dry to wet conditions.

Rock fall hazard assessment in Asar Hill, ancient Mabolla City, Mugla—SW Turkey

This paper discusses the potential rock fall hazard of Asar Hill. This flat-topped hill, containing Upper Miocene conglomerate and finer-grained sedimentary rocks, hosts to the ancient Mabolla City. The seasonal temperature differences are high in this rainy region. Block sizes, bed, and joints attitudes were measured along three profiles during field study. Schmidt Hammer was applied to grains and matrix of conglomerates for determining strength in situ. One joint set in Profile A, 3 in Profile B, and 4 in Profile C were determined via dips analysis. An intersection of joints and bedding (directed 25°–35°NW) caused the block formation, control slope, angle and mass movement type. At least 10 blocks (0.6–1241.085 tons) were fixed on top of profiles. Two blocks on top of the eastern Profile A contain archaeological ruins. After back analysis for determining restitution coefficients, RocFall version 4.9 software program was used to determine possible end points of those blocks. Most of the blocks can reach the valley and pass the other side, which includes settlements and gardens. Consequently the possible rock fall hazard in Asar hill is threatening visitors and settlers. The cleaning of detached blocks on top of slope is one of the easiest ways. However, in situ preservation of blocks with archaeological ruins via tensioned rock anchors and/or patterned rock bolts has vital importance. Relocation of settlers and gardens, opening trench around hill, and establishing green belt-forest would be considered as other measures.

Slips, Trips, and Falls in Homes: Home Health Care Workers at Risk

Abstract Date Presented 4/7/2016 This session presents the major slip, trip, and fall hazards faced by home health care workers (HHWs) in client homes. It also details the solutions currently used by HHW to mitigate these hazards—some effective and some not. Roles for occupational therapy experts in home modification and fall prevention will be discussed. Primary Author and Speaker: Amy Darragh Contributing Authors: Carolyn Sommerich, Steve Lavender, Celia Wills, Barbara Polivka, Donald Stredney

Social Isolation and Physical Barriers in the Houses of Stroke Survivors in Rural China

ObjectiveTo describe the home barriers and social isolation of stroke survivors in the rural areas of China and to explore which home barriers are associated with social isolation. DesignCross-sectional survey. SettingStructured interviews and observation in the participants' homes. ParticipantsCommunity-dwelling stroke survivors in the rural areas of China (N=818). InterventionsNot applicable. Main Outcome MeasuresPhysical barriers in rural homes were surveyed using a home fall hazards assessment. Social isolation was identified if ≥2 of the following indicators were observed: low frequency of getting out of the home, lacking leisure activities, and living alone in the previous 3 months. ResultsThe prevalence rates of 18 among 30 home barriers were >20%, and the highest was 93% (lack of handrails in the bathroom). The prevalence of social isolation was 30%. Three home barriers were independently related to social isolation. These were a distant toilet (odds ratio [OR], 2.363; 95% confidence interval [CI], 1.527–3.658; P<.001), unsuitable seating (OR, 1.571; 95% CI, 1.026–2.404; P=.038), and inaccessible light switches (OR, 1.572; 95% CI, 1.064–2.324; P=.023). ConclusionsMany barriers exist in the houses of stroke survivors in rural China. Some of them are related to social isolation. Eliminating or decreasing home barriers could be a feasible and effective approach to reducing social isolation.