Comparative Study on the Perception of Construction Safety Risks in China and Australia

Safety is a major concern in the construction industry because fatalities and injuries from construction work bring great losses to individuals, organizations, and societies as a whole. This paper aims to understand how construction personnel perceive safety risks in China as compared with those in Australia. Postal questionnaire surveys were used to collect data on safety risk perceptions from the two nations. The safety risk factors were assessed using a risk significance index based on the likelihood of occurrences and the impacts on safety performance. The survey results revealed that in China the main perception of safety risks came from human-and/or procedure-related issues, with “low/no safety education” paramount, followed by “inadequate fire prevention and electrical prevention procedures,” etc. In contrast, the major safety risks perceived in Australia were related to the environment and physical site conditions with “contamination of land, water and air” ranked first, followed by “unforeseen excavation of soil,” etc. To minimize construction safety risks in China, this paper suggests that the government should develop collective legislation and safety protection procedures, and enforce safety education and training to all site participants. Risks related to environmental and site conditions were generally realized by the Australia construction industry, which were not highly acknowledged in China. This may also bring imminent attention in this regard to the Chinese government.     

Safety Risk Identification and Assessment for Beijing Olympic Venues Construction

New technologies, new materials, and innovative designs have been extensively adopted in Beijing Olympic venues construction. The extreme requirements for time deadline and competition function expose the venues construction to high risks. These risks would potentially bring negative impacts on the site safety performance. Meanwhile, there is a lack of systematic management for safety risks in China’s construction industry, especially for large projects such as the Beijing Olympic venues construction. This paper identifies and assesses safety risk factors inherent in Beijing Olympic venues construction with the involvement of 27 experienced and highly respected experts from government agencies, the construction industry, and academe through brainstorming, workshop discussions, and questionnaire surveys. The finding reveals that more than half of the critical safety risk factors are from contractors and subcontractors such as: lack of emergency response plan and measures; workers’ unsafe operation, and contractors ignoring safety under schedule pressure. Based on these critical safety risks, a risk register is composed and a model is developed in application of the analytic hierarchy process to assess the status of risks on site safety. The model has been attempted in two Olympic venue projects under construction and the validity has been approved. The risk checklist, register, and assessment model developed in the paper were integrated into the risk management system that has been used for Beijing Olympic venues construction.     

Risk-Based Safety Impact Assessment Methodology for Underground Construction Projects in Korea

Safety of construction projects may be affected by various factors such as types and scale of projects, construction methods, safety management procedure, climate, site conditions, etc. Among them is the quality of design in relation to safety. Presently, however, designers typically are not involved in construction safety. They are often uncertain of their responsibilities in relation to construction safety and fail to be responsible for avoiding or reducing safety-related risks. In this study, the concept of safety impact assessment to achieve “design-for-safety” in the design phase is introduced. For this purpose, a safety impact assessment model was devised, and a methodology using the risk-based safety impact assessment approach for open-cut type underground construction projects in Korea is suggested. The suggested methodology includes a safety information survey, classification of safety impact factors caused by design and construction, and quantitative estimation of magnitude and frequency of safety impact factors. A checklist which can be easily used for assessing the safety performance of design products is also proposed. A real-world case study on the safety impact assessment of a subway construction project in Korea is also provided in the paper.     

Scheduling-Based Risk Estimation and Safety Planning for Construction Projects

This paper considers the issue of safety risks on construction sites. It introduces the concept of combined effect of different risk factors to the accident. For proper safety planning, safety managers need to be well aware of the direct causes of the accident as well as indirect factors that adversely effect on site safety. If it is observed that if a hazardous environment exists at the site, then either that hazardous environment must be eliminated or occupations and processes related to that hazard must be properly protected. One of the measures for evading such hazardous situations is to predict such situations and to reschedule the start time of high-risk situation so that risks are not concentrated during certain periods and at certain locations. In order to predict when and where the risk will reach its highest level, analysis should be performed based upon various information including statistical sources such as accident histories and this should be done in coordination with the activity scheduling. This paper analyzes the result of accident history and provides information about vulnerable situations. In addition, it presents a theory of safety planning method which estimates the risk distribution of a project and helps the safety manager to both estimate situations of concentrated risk and then to reschedule it when it is necessary.     

Construction Safety Risk Mitigation

Construction safety and health management has improved significantly following the Occupational Safety and Health Act of 1970. In response to this legislation, contractors began implementing safety programs to reduce occupational safety and health hazards on construction sites. Researchers recently found that the current process of selecting specific elements for a safety program is informal. This paper describes the results of a recent study designed to determine the relative effectiveness of safety program elements by quantifying their individual ability to mitigate construction safety and health risks. In order to determine the effectiveness of individual safety program elements, the following research activities were performed: (1) an appropriate safety risk classification system was created using an aggregation of relevant literature; (2) highly effective safety program elements were identified in literature; and (3) the ability of each safety program element to mitigate a portion of each of the safety risk classes was quantified using the Delphi method. The results of the research indicate that the most effective safety program elements are upper management support and commitment and strategic subcontractor selection and management and the least effective elements are recordkeeping and accident analyses and emergency response planning. It is expected that the data presented in this paper can be used to strategically select elements for a safety program, target specific safety and health risks, and influence resource allocation when funds are limited.     

Genetic Algorithm for Solving Site Layout Problem with Unequal-Size and Constrained Facilities

This paper presents an investigation of the applicability of a genetic approach for solving the construction site layout problem. This problem involves coordinating the use of limited site space to accommodate temporary facilities so that transportation cost of materials is minimized. The layout problem considered in this paper is characterized by affinity weights used to model transportation costs between facilities and by geometric constraints that limit their relative positions on site. The proposed genetic algorithm generates an initial population of layouts through a sequence of mutation operations and evolves the layouts of this population through a sequence of genetic operations aiming at finding an optimal layout. The paper concludes with examples illustrating the strength and limitations of the proposed algorithm in the cases of (1) loosely versus tightly constrained layouts with equal levels of interaction between facilities; (2) loosely versus tightly packed layouts with variable levels of interactions between facilities; and (3) loosely versus tightly constrained layouts. In most problems considered where the total-objects-to-site-area ratio did not exceed 60%, the algorithm returned close to optimal solutions in a reasonable time.     

Conjoining MMAS to GA to Solve Construction Site Layout Planning Problem

An optimal construction site layout planning (CSLP) is vital for project management. It can reduce the transportation flows and thus the costs of a project. Genetic algorithm (GA) is the most used algorithm to solve site layout problems, but randomly generated initial population in GA will decrease solution quality. Max-min ant system (MMAS) can offer a better initial population than the randomly generated initial population at the beginning of GA. In this study, a modified GA (MMAS-GA) formed by conjoining MMAS to the step of initialization of GA is proposed to solve CSLP problems. In order to reveal the computational capability of MMAS-GA to solve CSLP problems, the results of MMAS-GA and traditional GA are compared by solving an equal-area CSLP problem. The results showed that the proposed MMAS-GA algorithm provided a better optimal solution under the objective function of minimizing the transportation flows between the site facilities. The proposed MMAS-GA algorithm could assist project managers and planners to design optimal construction site layout, and thus to reduce construction costs.     

Time-Lapse Digital Photography Applied to Project Management

A discussion about movies used to monitor activities on a construction site is presented. A new concept in time-lapse photography is introduced, where the user records pictures of a construction site shot at an optimal frame rate and is able to playback time-lapse movies at lower frame rates, this way adjusting the running time and detail of the playback movie. A software package is built in the Windows visual environment, capable of generating a time-lapse movie of a desired frame rate from a regular digital movie shot at the construction site. The selection of the most appropriate frame rate to handle different managerial issues such as analyzing claims, investigating accidents, and monitoring progress is discussed. Solutions are sought to the problem of storing the vast amount of digital information generated by movies, using commercially available storage devices.     

Measuring Safety Climate of a Construction Company

Safety climate can benefit contractors, specialty contractors, and owners of industries by providing them with the knowledge of attitudes and perceptions that can help to consistently achieve better safety performance. The objective of this research was to determine safety climate that would enhance safety culture and positively impact perceived safety performance on construction projects. A safety climate questionnaire survey was conducted on the construction sites of a leading construction company and its subcontractors in Hong Kong. Approximately, 1,500 hard copy questionnaires were distributed and the response rate was excellent, resulting in 1,120 valid questionnaires being collected from 22 construction projects. By means of factor analysis, two underlying safety climate factors were extracted, accounting for 43.9% of the total variance. Multiple regression analysis confirmed that these climate factors, “management commitment and employee involvement” and “inappropriate safety procedure and work practices” were significant predictors of workers’ perceptions of safety performance. The findings indicated that the relationship between perceived safety performance and “inappropriate safety procedure and work practices” was inversely correlated. The results suggest that safety climate can be used as an effective measure of assessing and improving site safety for projects under construction. The findings of this study and the methodology might be useful for research at other construction sites in other regions and countries. This work provides useful information for project managers and safety practitioners who desire to improve safety climate and safety performance on construction sites.     

Assessment of Safety Performance Measures at Construction Sites

Various methods for the measurement and classification of safety performance at construction sites, e.g., timing relative to the moment of accident, data collection method, safety effectiveness criterion, performance measure, and frequency and severity of the measured event, are analyzed. The effectiveness of the various methods and the extent of their use at construction sites are examined. Attributes that are investigated include efficiency, reliability, and validity and diagnostic capacity of the measure in order to identify the cause for success or failure, respectively, of the safety program at a site. The data for the study were collected through questionnaires which were addressed to the largest construction companies in the United States. The most effective and the most widely employed measurement methods were lost‐day cases, doctor's cases, and cost of accidents. The least effective and most limited in use were the no‐injury cases.     

Safety Climate in Construction Site Environments

This paper discusses empirical research aimed at examining the relationship between the safety climate and safe work behavior in construction site environments. A literature review has identified a number of independent constructs with the potential to affect the safety climate. A research model was developed based on the hypothesis that safe work behaviors are consequences of the existing safety climate, which, in turn, is determined by the identified independent constructs. A questionnaire survey was used in order to facilitate the collection of information from construction sites. The model was tested using structural equation modeling. The paper presents the results of testing the research model. The results corroborate the importance of the role of management commitment, communication, workers’ involvement, attitudes, competence, as well as supportive and supervisory environments, in achieving a positive safety climate.     

Viability of Designing for Construction Worker Safety

Designing for construction safety entails consideration of the safety of construction workers in the design of a project. Research studies have identified the design aspect of projects as being a significant contributing factor to construction site accidents. Designing to eliminate or avoid hazards prior to exposure on the jobsite is also listed as the top priority in the hierarchy of controls common to the safety and health professions. Widespread implementation of the concept in the United States by engineering and architecture firms, however, is lacking due to perceived industry and project barriers. Given its absence from standard design practice, a question arises as to the viability of designing for safety as an intervention in the construction industry. This paper presents a pilot study that was conducted to investigate the practice of addressing construction worker safety when designing a project and to determine the feasibility and practicality of such an intervention. Through interviews of architects and engineers, the study found that a large percentage of design professionals are interested and willing to implement the concept in practice. Among the perceived impacts of implementation, project cost and schedule were mentioned most often along with limitations being placed on design creativity. The results of the pilot study indicate that designing for safety is a viable intervention in construction. The factors that impact the consideration of safety in the design of a project do not entirely prohibit its implementation or make its implementation extremely impractical and therefore not feasible. Additionally, the outcomes of implementation provide sufficient motivation to implement the concept in practice. The paper describes the key changes needed for implementation of the concept in practice which include: a change in designer mindset toward safety; establishment of a motivational force to promote designing for safety; increase designer knowledge of the concept; incorporate construction safety knowledge in the design phase; utilize designers knowledgeable about design-for-safety modifications; make design for safety tools and guidelines available for use and reference; and mitigate designer liability exposure.     

Optimizing Airport Construction Site Layouts to Minimize Wildlife Hazards

Construction operations in airport expansion projects often attract wildlife species to critical airport traffic areas leading to an increase in the risk of wildlife–aircraft collision accidents. Airport operators and construction planners need to carefully consider and minimize these wildlife hazards during the planning of construction site layouts in order to comply with Federal Aviation Administration recommendations. This paper presents the development of an advanced optimization model for planning airport construction site layouts that is capable of minimizing the hazards of wildlife attractants and minimizing the site layout costs, simultaneously. The model incorporates newly developed concepts and performance criteria that enable (1) quantifying, controlling, and minimizing the hazards of construction-related wildlife attractants near airport traffic areas; and (2) minimizing the travel cost of construction resources and the cost of devices installed to control wildlife on airport construction sites, while complying with all relevant aviation safety constraints. The model is developed using a multiobjective genetic algorithm and an application example is analyzed to demonstrate the use of the model in optimizing airport construction site layouts and its unique capability of generating optimal trade-offs between wildlife control and site layout costs.     

Bootstrap Technique for Risk Analysis with Interval Numbers in Bridge Construction Projects

Bridges are principal and vital transportation structures. If risk management is not considered in bridge construction projects, objectives cannot be delivered on time, on budget, or with suitable quality results. Risk data set sizes and experts’ judgments are not usually sufficient for analyzing significant risks in bridge construction projects; moreover, the statistical distributions for risk parameter estimates are usually unknown. Standard parametric statistical techniques cannot provide appropriate solutions for cases with small data sets or unknown distributions. This paper proposes a new hybrid approach by using a nonparametric resampling technique and interval computations for risk analysis, in particular, for bridge construction projects. Bootstrap techniques produce more accurate inferences for comparing parametric techniques and are an alternative when the underlying parametric assumptions are not considered. Increasingly, because of the complexity and uncertainty in decision making at bridge projects, it is easier or more natural to provide interval values for parts or all of decision-making judgments. Furthermore, the goal of reducing standard deviations for both risk probability and risk impact compared with the conventional approach is another conclusion of this paper. The proposed approach is applied to a case in Iran to show the validity of the approach.     

Construction Risks: Single versus Portfolio Insurance

Risks and uncertainties are naturally inherent in the construction industry and negatively affect contracting parties and executed projects. This paper explores the possibility of insuring against construction risks, which are beyond the control of contractors and not covered by surety policies, through single and portfolio insurance strategies. Accordingly, the writers programmed Iman and Conover’s bootstrapping method for inducing correlations using Microsoft Excel and consequently, developed a technique for pricing insurance premiums as an exotic option using Monte Carlo simulation. The aforementioned methodology was applied on a data set of five defined risks that were collected from small, medium, and large scale projects in California. Pursuant to this study, the calculated premiums for insuring against the defined risks are in line with the premiums available in market for other insurance policies. Moreover, the estimated premium for the proposed portfolio insurance product is more advantageous to contractors in both risk coverage and cost because it is well below the estimated premiums for single insurance products covering individual risks. It is foreseen that this research could open horizons for new construction related insurance products, which would significantly contribute to the efficiency of the risk management process in the construction industry.     

Benchmarking Studies on Construction Safety Management in China

This paper presents information by which to measure safety management performance on construction sites. In China, the conventional construction safety benchmarking approach is to assess safety performance by evaluating the physical safety conditions on site as well as the accident records, while no attention has been paid to the management factors that influence site safety. This paper is to identify the key factors that influence safety management and to develop a method for measuring safety management performance on construction sites. Based on the survey and interview data collected on safety management factors in 82 construction projects in China, the safety management index as a means to evaluate real-time safety management performance by measuring key management factors was developed. The quantified factors were compared with the commonly accepted physical safety performance index, which was derived from inspection records of physical safety conditions, accident rates, and the satisfaction of the project management team. Multifactor linear regression was conducted and the result indicates that safety management performance on site is closely related to organizational factors, economic factors, and factors related to the relationship between management and labor on site. Based on this benchmarking study, a practical safety assessment method was developed and then implemented on six construction projects. The results show that this method can be an effective tool to evaluate safety management on construction projects.     

Population and Initial Validation of a Formal Model for Construction Safety Risk Management

The transient, unique, and complex nature of construction projects makes safety management exceptionally difficult. Most construction safety efforts are applied in an informal fashion under the premise that simply allocating more resources to safety management will improve site safety. Currently, there is no mechanism by which construction-site safety professionals may formally evaluate safety risk and select safety program elements for implementation. This paper introduces and validates a risk-based safety and health analytical model that can be used to evaluate expected risk given specific worker activities, strategically select highly effective safety program elements for implementation when resources are limited, and quantify resulting risk once the identified safety elements have been implemented. Specifically, the paper has three primary objectives: (1) introduce a risk-based construction safety and health analytical model; (2) validate relevant data used to populate the model; and (3) illustrate the applications of the model in practice. The findings of this research indicate that the values used to populate the model are reliable and that the model has the potential to significantly improve construction safety management.     

Transportation Agency Use of Owner-Controlled Insurance Programs

Controlled insurance programs are highly efficient risk control mechanisms. With a controlled insurance program, the interest of the owner, designer, construction manager, contractors, and consultants are covered by one insurance arrangement. This paper describes the current state of practice regarding the use of owner-controlled insurance programs by transportation agencies. Departments of transportation that have used controlled insurance programs for their major projects (construction costs greater than $100 million) report that they were satisfied with the results. But contractors are cautious because, when an owner’s controlled insurance program administrator fails to perform, it is the contractor who incurs the residual consequences of increased business cost, and those consequences can extend far into the future.     

Trade-off between Safety and Cost in Planning Construction Site Layouts

Planning construction site layouts involves identifying the positions of temporary facilities on site, and accordingly it has a significant impact on the safety and efficiency of construction operations. Although available models are capable of minimizing the travel cost of resources on site, they do not consider safety as an important and separate objective in the optimization of site layouts. This paper presents the development of an expanded site layout planning model that is capable of maximizing construction safety and minimizing the travel cost of resources on site, simultaneously. The model incorporates newly developed concepts and performance criteria that enable the quantification of construction safety and travel cost of resources on site. The present model is developed in three main phases: (1) formulating decision variables and optimization objectives in this site layout planning problem; (2) identifying and satisfying all practical constraints in this optimization problem; and (3) implementing the model as a multiobjective genetic algorithm. An application example is analyzed to illustrate the use of the model and demonstrate its capabilities in optimizing construction site layouts and generating optimal trade-offs between safety and travel cost of resources on site.