Investigating risk factors for slips, trips and falls in New Zealand residential construction using incident-centred and incident-independent methods

Slip, trip and fall (STF) incidents, particularly falls from a height, are a leading cause of injury in the New Zealand residential construction industry. The most common origins of falls from a height in this sector are ladders, scaffolding and roofs, while slipping is the most frequent fall initiating event category. The study aimed to provide detailed information on construction industry STF risk factors for high-risk tasks, work equipment and environments, as identified from an earlier analysis of STF claims data, together with information to be used in the development of interventions to reduce STF risk in New Zealand residential construction. The study involved the use of both incident-centred and incident-independent methods of investigation, including detailed follow-up investigations of incidents and observations and interviews with workers on construction sites, to provide data on a wide range of risk factors. A large number of risk factors for residential construction STFs were identified, including factors related to the work environment, tasks and the use and availability of appropriate height work equipment. The different methods of investigation produced complementary information on factors related to equipment design and work organization, which underlie some of the site conditions and work practices identified as key risk factors for residential construction STFs. A conceptual systems model of residential construction STF risk is presented.     

Investigating slips,trips and falls in the New Zealand dairy farming sector

The paper presents findings from 39 detailed follow-up investigations of slips, trips and falls (STF) incurred by individuals working in New Zealand's dairy farming industry. The study sought to identify the key contributory risk factors for STF in this sector to provide evidence to support intervention design, and to determine the effectiveness of the investigative methodology used to achieve these objectives. Findings from the follow-up investigations included an analysis of factors related to the underfoot surface, underfoot hazard and footwear. Of note here was the propensity for STF-involved workers to not see or identify an underfoot hazard due to concurrent visual task distractions, and for workers to use footwear that both lacked effective tread and was unsuitable for the task and underfoot surface. Key latent risk factors and their interactions identified included problems associated with time pressure and related time-saving behaviours and the presence of design errors that, for example, required workers to climb onto equipment to view aspects of the task they were working on. The paper concludes that the potential resource and logistical problems associated with conducting detailed STF investigations are outweighed by the opportunity to collect rich data on key risk factors and their interactions in STF research.     

Preventing falls from roofs: a critical review

Work-related falls from roofs remain a significant problem for workers in the construction industry. Knowledge about the main causative or initiating factors leading to fall incidents is desperately needed for fall prevention intervention. From biomechanical and psychophysiological perspectives the majority of occupational falls, including falls from roofs, can be regarded as loss-of-balance incidents. The primary objective of this paper is to summarize the current knowledge from multiple fields about factors that are related to the control of balance during roofing work. An extensive literature review identified a number of environmental, task-related and personal factors that degrade the control of balance and could be associated with the initiation of falls from roofs. These factors include visual exposure to elevation; unstable visual cues and inadequate visual information in the work environment; 'confined' and inclined support surfaces; unexpected changes in roof surface properties; load handling; physical exertion; fatigue; task complexity that diverts workers' attention; individual differences; work experience and training; and personal protective equipment. Current measures to reduce falls from roofs focus mainly on fall protection procedures, such as the use of covers, guardrails, safety nets, and personal fall-arrest systems, or the application of warning-line systems, safety monitoring systems, and fall protection plans. In many instances, these procedures are not practical for the industry and current regulations allow the use of alternative means of fall protection, such as slide guards. Future research on preventing falls from roofs should consider the main effects and interactions of the environmental, task-related and personal factors that affect the balance control of workers. Research-supported improvements in the visual and physical characteristics of the roof work environment, the construction materials and methods, and work procedures and practices may result in improved workers' balance control as well as overall safety performance, and would ultimately reduce incidents of falling from a roof.     

Preventing falls from roofs: a critical review

Work-related falls from roofs remain a significant problem for workers in the construction industry. Knowledge about the main causative or initiating factors leading to fall incidents is desperately needed for fall prevention intervention. From biomechanical and psychophysiological perspectives the majority of occupational falls, including falls from roofs, can be regarded as loss-of-balance incidents. The primary objective of this paper is to summarize the current knowledge from multiple fields about factors that are related to the control of balance during roofing work. An extensive literature review identified a number of environmental, task-related and personal factors that degrade the control of balance and could be associated with the initiation of falls from roofs. These factors include visual exposure to elevation; unstable visual cues and inadequate visual information in the work environment; ‘confined’ and inclined support surfaces; unexpected changes in roof surface properties; load handling; physical exertion; fatigue; task complexity that diverts workers' attention; individual differences; work experience and training; and personal protective equipment. Current measures to reduce falls from roofs focus mainly on fall protection procedures, such as the use of covers, guardrails, safety nets, and personal fall arrest systems, or the application of warning-line systems, safety monitoring systems, and fall protection plans. In many instances, these procedures are not practical for the industry and current regulations allow the use of alternative means of fall protection, such as slide guards. Future research on preventing falls from roofs should consider the main effects and interactions of the environmental, task-related and personal factors that affect the balance control of workers. Research-supported improvements in the visual and physical characteristics of the roof work environment, the construction materials and methods, and work procedures and practices may result in improved workers' balance control as well as overall safety performance, and would ultimately reduce incidents of falling from a roof.     

Investigating slips, trips and falls in the New Zealand dairy farming sector

The paper presents findings from 39 detailed follow-up investigations of slips, trips and falls (STF) incurred by individuals working in New Zealand's dairy farming industry. The study sought to identify the key contributory risk factors for STF in this sector to provide evidence to support intervention design, and to determine the effectiveness of the investigative methodology used to achieve these objectives. Findings from the follow-up investigations included an analysis of factors related to the underfoot surface, underfoot hazard and footwear. Of note here was the propensity for STF-involved workers to not see or identify an underfoot hazard due to concurrent visual task distractions, and for workers to use footwear that both lacked effective tread and was unsuitable for the task and underfoot surface. Key latent risk factors and their interactions identified included problems associated with time pressure and related time-saving behaviours and the presence of design errors that, for example, required workers to climb onto equipment to view aspects of the task they were working on. The paper concludes that the potential resource and logistical problems associated with conducting detailed STF investigations are outweighed by the opportunity to collect rich data on key risk factors and their interactions in STF research.     

Evaluation of a comprehensive slip, trip and fall prevention programme for hospital employees

In 2007, the Bureau of Labor Statistics reported that the incidence rate of lost workday injuries from slips, trips and falls (STFs) on the same level in hospitals was 35.2 per 10,000 full-time equivalents (FTE), which was 75% greater than the average rate for all other private industries combined (20.2 per 10,000 FTEs). The objectives of this 10-year (1996-2005) longitudinal study were to: 1) describe occupational STF injury events in hospitals; 2) evaluate the effectiveness of a comprehensive programme for reducing STF incidents among hospital employees. The comprehensive prevention programme included analysis of injury records to identify common causes of STFs, on-site hazard assessments, changes to housekeeping procedures and products, introduction of STF preventive products and procedures, general awareness campaigns, programmes for external ice and snow removal, flooring changes and slip-resistant footwear for certain employee subgroups. The hospitals' total STF workers' compensation claims rate declined by 58% from the pre-intervention (1996-1999) rate of 1.66 claims per 100 FTE to the post-intervention (2003-2005) time period rate of 0.76 claims per 100 FTE (adjusted rate ratio = 0.42, 95% CI: 0.33-0.54). STFs due to liquid contamination (water, fluid, slippery, greasy and slick spots) were the most common cause (24%) of STF claims for the entire study period 1996-2005. Food services, transport/emergency medical service and housekeeping staff were at highest risk of a STF claim in the hospital environment. Nursing and office administrative staff generated the largest numbers of STF claims. STF injury events in hospitals have a myriad of causes and the work conditions in hospitals are diverse. This research provides evidence that implementation of a broad-scale prevention programme can significantly reduce STF injury claims.     

The role of latent and active failures in workplace slips, trips and falls: an information processing approach

The vast majority of the published workplace slips, trips and falls (STF) literature is exceedingly narrow in its focus and often ignores wider systems issues in workplace STF aetiology. There is little recognition within the published literature of the importance of latent failures or the upstream organisational and cultural contexts within which workplace STF occur. This is unfortunate, as a systems approach to workplace STF analysis, that is inclusive of latent design and work organisation factors that often shape worker behaviour patterns related to STF risk (e.g. rushing, risk taking), is fundamental to the development of effective prevention measures. The aims of this paper are to provide an understanding of workplace STF causation that is cognisant of the potential role of both active and latent failures in STF causation. The paper presents an ergonomics model for workplace STF analysis that highlights information processing in STF aetiology, the STF incident process and the interaction between latent and active failures in STF causation. The paper draws upon ergonomics research conducted in a range of occupational contexts to illustrate the key features of the model as it applies to workplace STF. Implications of the model for analysis and prevention of STF are discussed.     

Accident patterns and prevention measures for fatal occupational falls in the construction industry

Contributing factors to 621 occupational fatal falls have been identified with respect to the victim's individual factors, the fall site, company size, and cause of fall. Individual factors included age, gender, experience, and the use of personal protective equipment (PPE). Accident scenarios were derived from accident reports. Significant linkages were found between causes for the falls and accident events. Falls from scaffold staging were associated with a lack of complying scaffolds and bodily action. Falls through existing floor openings were associated with unguarded openings, inappropriate protections, or the removal of protections. Falls from building girders or other structural steel were associated with bodily actions and improper use of PPE. Falls from roof edges were associated with bodily actions and being pulled down by a hoist, object or tool. Falls through roof surfaces were associated with lack of complying scaffolds. Falls from ladders were associated with overexertion and unusual control and the use of unsafe ladders and tools. Falls down stairs or steps were associated with unguarded openings. Falls while jumping to a lower floor and falls through existing roof openings were associated with poor work practices. Primary and secondary prevention measures can be used to prevent falls or to mitigate the consequences of falls and are suggested for each type of accident. Primary prevention measures would include fixed barriers, such as handrails, guardrails, surface opening protections (hole coverings), crawling boards/planks, and strong roofing materials. Secondary protection measures would include travel restraint systems (safety belt), fall arrest systems (safety harness), and fall containment systems (safety nets).     

Zeitschrift für Arbeitswissenschaft Abstracts of papers,Vol. 42 (14 NF), Part 1, 1988

This study sought to identify causal factors for slip, trip and fall accidents occurring during the delivery of mail. Analysis of in-house data produced information about accident circumstances for 1734 fall cases. The most common initiating events in delivery falls were slips and trips. Slips most often occurred on snow, ice or grass, while trips tended to involve uneven pavements, obstacles and kerbs. Nearly one-fifth of falls occurred on steps, with step falls requiring longer absence from work than falls on the level. Half of all falls occurred during November-February and three-quarters of falls occurred between 7 and 9 a.m. Incidence rates for female employees were 50% higher than for their male colleagues. Accident-independent methods included interviews with safety personnel and managers, discussion groups with delivery employees, and a questionnaire survey of employees and managers. These techniques provided data on risk factors related to the task, behaviour, footwear and equipment. Arising from these accident-independent investigations, it is suggested that unsafe working practices, such as reading addresses while walking and taking shortcuts, increase the risk of falls. Organizational issues include management safety activities, training and equipment provision. Measures are discussed that might lead to a reduction in the incidence of delivery fall accidents.     

Occupational slip,trip, and fall-related injuries can the contribution of slipperiness be isolated?

To determine if the contribution of slipperiness to occupational slip, trip and fall (STF)-related injuries could be isolated from injury surveillance systems in the USA, the UK and Sweden, six governmental systems and one industrial system were consulted. The systems varied in their capture approaches and the degree of documentation of exposure to slipping. The burden of STF-related occupational injury ranged from 20 to 40% of disabling occupational injuries in the developed countries studied. The annual direct cost of fall-related occupational injuries in the USA alone was estimated to be approximately US$6 billion. Slipperiness or slipping were found to contribute to between 40 and 50% of fall-related injuries. Slipperiness was more often a factor in same level falls than in falls to lower levels. The evaluation of the burden of slipperiness was hampered by design limitations in many of the data systems utilized. The resolution of large-scale injury registries should be improved by collecting more detailed incident sequence information to better define the full scope and contribution of slipperiness to occupational STF-related injuries. Such improvements would facilitate the allocation of prevention resources towards reduction of first-event risk factors such as slipping.     

A comparison of the burden and resultant risk associated with occupational falls from a height and on the same level in Australia

Occupational falls are one of the leading causes of occupational injury and death internationally. This study described the nature of occupational falls following an analysis of workers compensation data in Western Australia. Frequencies, proportions and incidence rates were calculated following mechanism, gender, age and industry stratification. The natures of injury and bodily locations affected were compared between mechanisms of fall. Industry incidence rates were ranked and their corresponding proportions reported. Cost and lost time were described and risk scores for each burden type (incapacity, cost and lost time) were calculated and compared between fall mechanisms. Of all occupational falls, the proportion, incidence rates and risk scores of falls on same level were consistently greater compared to falls from a height. Gender, age and industry groups that appear to be at highest risk vary with the measure used and mechanism of incident. This study translates epidemiological information into a risk score that can aid in prioritisation.

Practitioner Summary: This paper presents an in-depth analysis of Worker’s Compensation claims for falls in Western Australia. Calculated proportion, incidence rates and formulated risk scores for falls on the level were consistently greater compared to falls from a height. Limitations associated with the analysis of large-scale data-sets are described.     

Height effects in real and virtual environments

The study compared human perceptions of height, danger, and anxiety, as well as skin conductance and heart rate responses and postural instability effects, in real and virtual height environments. The 24 participants (12 men, 12 women), whose average age was 23.6 years, performed "lean-over-the-railing" and standing tasks on real and comparable virtual balconies, using a surround-screen virtual reality (SSVR) system. The results indicate that the virtual display of elevation provided realistic perceptual experience and induced some physiological responses and postural instability effects comparable to those found in a real environment. It appears that a simulation of elevated work environment in a SSVR system, although with reduced visual fidelity, is a valid tool for safety research. Potential applications of this study include the design of virtual environments that will help in safe evaluation of human performance at elevation, identification of risk factors leading to fall incidents, and assessment of new fall prevention strategies.     

Occupational slip, trip, and fall-related injuries--can the contribution of slipperiness be isolated?

To determine if the contribution of slipperiness to occupational slip, trip and fall (STF)-related injuries could be isolated from injury surveillance systems in the USA, the UK and Sweden, six governmental systems and one industrial system were consulted. The systems varied in their capture approaches and the degree of documentation of exposure to slipping. The burden of STF-related occupational injury ranged from 20 to 40% of disabling occupational injuries in the developed countries studied. The annual direct cost of fall-related occupational injuries in the USA alone was estimated to be approximately US$6 billion. Slipperiness or slipping were found to contribute to between 40 and 50% of fall-related injuries. Slipperiness was more often a factor in same level falls than in falls to lower levels. The evaluation of the burden of slipperiness was hampered by design limitations in many of the data systems utilized. The resolution of large-scale injury registries should be improved by collecting more detailed incident sequence information to better define the full scope and contribution of slipperiness to occupational STF-related injuries. Such improvements would facilitate the allocation of prevention resources towards reduction of first-event risk factors such as slipping.     

Slip, trip and fall accidents: relationship to building features and use of coroners' reports in ascribing cause

Coroners' reports of 1035 deaths possibly related to building features were examined to assess their usefulness in identifying the cause of slip, trip and fall (STF) fatalities. Of the total, falls accounted for over 80%. Of the STF deaths, 61.4% related to falls on stairs, 6.7% to falls from steps or ladders, and 5.5% to falls from windows or roofs. About 60% of total fall fatalities involved infirm persons; alcohol was involved in 60% of the falls in the under-50 age group. Information in coroners' reports is generally insufficient to link building features to injuries; better approaches to data collection are required.     

Low back injury risks during construction with prefabricated (panelised) walls: effects of task and design factors

New technology designed to increase productivity in residential construction may exacerbate the risk of work-related musculoskeletal disorders (WMSDs) among residential construction workers. Of interest here are panelised (prefabricated) wall systems (or panels) and facilitating an ongoing effort to provide proactive control of ergonomic exposures and risks among workers using panels. This study, which included 24 participants, estimated WMSD risks using five methods during common panel erection tasks and the influences of panel mass (sheathed vs. unsheathed) and size (wall length). WMSD risks were fairly high overall; e.g. 34% and 77% of trials exceeded the 'action limits' for spinal compressive and shear forces, respectively. Heavier (sheathed) panels significantly increased risks, although the magnitude of this effect differed with panel size and between tasks. Higher levels of risk were found in tasks originating from ground vs. knuckle height. Several practical recommendations based on the results are discussed. STATEMENT OF RELEVANCE: Panelised wall systems have the potential to increase productivity in residential construction, but may result in increased worker injury risks. Results from this study can be used to generate future panel design and construction processes that can proactively address WMSD risks.     

An analysis of sprain and strain injury data for the New Zealand meat processing industry from national and industry injury surveillance databases

Data on musculoskeletal disorders (MSD) in meat processing and the tasks in which they occur is limited in the literature. This paper provides a summary of such data from the New Zealand industry. Despite the high incidence of MSD in meat processing in New Zealand, little research has been undertaken to identify and assess high-risk tasks and develop interventions to address them. This paper reports on the initial stages of a 2-year government funded project to address these issues. Findings are presented from the analysis of data from two injury surveillance databases. Accident Compensation Corporation national data claims assisted in defining the industry and indicated factors for further assessment, including consideration of claimants' gender, ethnicity and geographical region. National Injury Database industry data claims helped to identify specific tasks in which MSD are more likely to occur by departments and for the two main animal species processed. These factors have helped shape the assessment of high-risk tasks currently undertaken in the meat processing industry.     

An analysis of sprain and strain injury data for the New Zealand meat processing industry from national and industry injury surveillance databases

Data on musculoskeletal disorders (MSD) in meat processing and the tasks in which they occur is limited in the literature. This paper provides a summary of such data from the New Zealand industry. Despite the high incidence of MSD in meat processing in New Zealand, little research has been undertaken to identify and assess high-risk tasks and develop interventions to address them. This paper reports on the initial stages of a 2-year government funded project to address these issues. Findings are presented from the analysis of data from two injury surveillance databases. Accident Compensation Corporation national data claims assisted in defining the industry and indicated factors for further assessment, including consideration of claimants' gender, ethnicity and geographical region. National Injury Database industry data claims helped to identify specific tasks in which MSD are more likely to occur by departments and for the two main animal species processed. These factors have helped shape the assessment of high-risk tasks currently undertaken in the meat processing industry.     

Cross-sectional investigation of task demands and musculoskeletal discomfort among restaurant wait staff

A cross-sectional study of task demands and musculoskeletal discomfort among a sample of 100 wait staff in ten casual dining restaurants was conducted. In addition to answering a questionnaire about musculoskeletal discomfort and symptoms experienced in the past 12 months and attributed to work, subjects were asked about various aspects of their jobs, such as shift length, number of shifts per week and safety training. The managers of the restaurants were also interviewed to gather basic information on factors such as work hours, alternative duty availability and safety practices. When asked to rank the three most important causes of injuries, the responses of both managers and wait staff were congruent with Bureau of Labor Statistics (USA) data for 1999 on the nature of injuries and attributed exposures, with slips and falls, musculoskeletal disorders and acute injuries (e.g. burns, cuts) highlighted. Of the 100 subjects, 42% reported experiencing musculoskeletal symptoms in the past year, with the lower back area (18%) and shoulder (11%) with the most frequent symptoms reported in the responses. Although many of the materials handling tasks were not excessive, the heavier tray lifts and carries are a cause for concern. There are also slip and fall issues that influence the risks of these tasks. Future research needs, including addressing the mismatch between more common materials handling assessment tools and the nature of food serving tasks, are discussed.