Construction Safety Personnel Qualifications: The Impact of Education, Experience, and Certification Programs

Construction is among the most hazardous industries, with an annual fatality rate of over 1000 workers in the United States. Researchers and practitioners have proclaimed that implementing effective safety management plans can prevent most construction accidents. Safety personnel, who oversee the design, implementation, and enhancement of safety management plans, play an essential role in preventing accidents and enhancing construction safety. Despite their important role, there is little research, if any, to examine if the actual qualifications of construction safety personnel match recommended qualifications by safety associations and professional organizations. Moreover, the impact of the qualifications of safety personnel on achieved safety outcomes has not yet been thoroughly examined. The present study aims to (1) examine if the qualifications of construction safety personnel match recommended qualifications by safety associations and professional organizations, and (2) empirically analyze the impact of three key safety personnel qualifications, namely education, experience, and certifications, on overall construction site safety performance. Sixty-five construction safety personnel participated in the study by responding to a questionnaire survey. Regression analysis between construction safety performance measured by the Total Recordable Incident Rate (TRIR) and three qualification criteria revealed that 1) higher levels of experience of safety personnel, as well as certificate programs, significantly contribute to lowering TRIR rates, and 2) the level of education of safety personnel is not statistically associated with lower or higher TRIR rates. The findings of this study contribute to the body of knowledge by highlighting the negative associations (1) between the level of experience and TRIR and (2) between certifications and TRIR—both of which are findings of practical value to safety personnel who aim to maximize their positive influence on safety performance. In particular, this finding justifies why construction management should prioritize experience level and safety certifications over education when selecting safety personnel.

KEY WORDS: construction safety, occupational accidents, qualifications, safety personnel

Construction is an important element in achieving a strong economy. The construction industry contributes approximately one billion dollars annually to the gross domestic product (GDP) in the United States (BEA, 2020). Globally, this number is about one thousand times greater, meaning that the construction industry contributes over $10 trillion to the gross world product (GWP) (Mckinsey Global Institute, 2017). The contribution of the construction industry is only possible due to the production of the industry workers (Kamas et al., 2019; Nnaji et al., 2022; Rasheed, 2016). Over 2% of the US population works in construction, which accounts for over 7 million individuals, with an anticipated annual increase of approximately half a million new employees (BLS1, 2020; BLS2, 2020). With all of their importance and critical role in maintaining a prosperous economy, the construction workforce faces significant challenges, especially in terms of maintaining their health and safety. Every year, the construction industry loses about 1,000 employees due to workplace fatalities, and many others become injured or disabled. In 2019, 1,061 employees were killed in workplace operations, according to the Bureau of Labor Statistics (BLS1, 2020). Construction employees face a risk of encountering a fatal accident that is 3-4 times higher than employees working in, say, the manufacturing industry (GÜRCANLI and MÜNGEN, 2013; Jin et al., 2019).

To curb the increasing number of workplace injuries and fatalities, it should be ensured that safety personnel leading the safety efforts on construction sites are well-qualified and have the necessary training, education, and experience. The probability of improving overall safety performance increases 2.29 times when having full-time safety personnel (Al-Bayati et al., 2020). The process of determining if safety personnel are well-qualified for a job is oftentimes subjective and does not follow recommendations or requirements provided by safety associations and professional organizations (Al-Bayati et al., 2019; Tam et al., 2004). However, there is no literature on determining if construction safety personnel are adequately qualified for the responsibility of their positions. Relatedly, few studies have examined the qualifications of safety personnel in the construction industry. Only a single study conducted by Awolusi et al. (2017) focused on the qualifications of construction safety personnel. The study of Awolusi et al. (2017) found that construction firms are equipped with higher numbers of safety personnel to manage construction activities than the staffing size recommended by existing literature on the topic. The ISO 45001-2018 standards titled “Occupational health and safety management systems — Requirements with guidance for use,” stresses that organizations should ensure their safety personnel is competent for the job responsibilities that they are upholding. It is recommended that competence be evaluated by three major elements: education, training, and experience. Accordingly, the goals of the present study are to (1) examine if the qualifications of construction safety personnel match recommended qualifications by safety associations and professional organizations, and (2) empirically analyze the impact of three key safety personnel qualifications (namely education, experience, and certifications) on overall construction site safety performance. Based on a review of existing literature, safety qualification is assessed by three key aspects: (1) education, (2) experience, and (3) certification (ASSP (American Society of Safety Professionals), 2016).

The first goal of this study is achieved using descriptive statistics. With respect to the second goal of the research study, a research hypothesis is developed and will be tested using inferential statistics. The hypothesis examines the association between safety performance measured by the TRIR, as shown in the subsequent section, and the qualifications of safety personnel with respect to three aspects: education, experience, and certifications. Accordingly, three research hypotheses were developed, as follows:

1. Education versus safety performance.
   1. Null hypothesis (1Ho): Higher levels of education of safety personnel are not associated with improved construction site safety performance.
   2. Alternative hypothesis (1H₁): Higher levels of education of safety personnel are associated with improved construction site safety performance.
2. Experience versus safety performance.
   1. Null hypothesis (2H_o): More years of experience are not associated with improved construction site safety performance.
   2. Alternative hypothesis (2H₁): More years of experience are associated with improved construction site safety performance.
3. Certifications versus safety performance.
   1. Null hypothesis (3H_o): Acquiring a safety certification is not associated with improved construction site safety performance.
   2. Alternative hypothesis (3H₁): Acquiring a safety certification is associated with improved construction site safety performance.

To test the research hypotheses stated in the previous section, the specific objectives are set for the present study, as follows:

• Assess the qualifications of safety personnel holding safety positions in the construction industry and whether they possess the minimum qualifications recommended by safety associations and professional organizations.
• Examine the association between three recommended qualifications (education, experience, and certification) and safety performance outcomes on construction projects.

For the second objective, the TRIR was considered the primary indicator to measure safety outcomes. Construction researchers and practitioners widely adopt TRIR to evaluate the safety performance of a construction company. According to the Occupational Safety and Health Administration (OSHA), TRIR is calculated by multiplying the total number of recordable cases by 200,000 and dividing by the total hours worked by all employees within a company during the year covered (Karakhan et al., 2018).

A questionnaire survey was developed and distributed to safety practitioner personnel who were responsible for construction safety management in the US. The authors developed a questionnaire survey for safety personnel and approved by the Lawrence Technological University’s Institutional Review Board (IRB). The questionnaire was pilot tested with three knowledgeable professionals active in construction health and safety management. This pilot testing ensured that the survey questions were practical and consistent with the terminology used in the industry and minimized any potential bias with the survey (Abowitz and Toole, 2010). The questionnaire was revised based on the feedback received from three professionals who participated in the pilot testing and distributed to the targeted audience via email. The researchers distributed the survey to safety professionals in their contacts and asked the participants to forward the survey to other safety personnel who uphold an active safety position within their firms. Thus, the researchers utilized a convenience sample (i.e., snowball), which is often used by construction scholars (Abowitz and Toole, 2010).

Corresponding to the research goals, the questionnaire consisted of three main parts. The first part focused on collecting demographic information about the survey participants, such as sector, organization type, job title, etc. The second part collected information about the participants’ qualifications (i.e., education, experience, and certification) and their safety roles. Finally, the third part solicited information pertaining to safety performance metrics of the participants’ firms, such as TRIRs and the number of dedicated full-time and part-time safety personnel within each company.

Sixty-five (65) construction safety practitioners participated in the study. The construction industry is known for lacking participation in surveys and questionnaires (Nabi and El-adaway, 2021). There is no clear threshold for sample size that should be considered for construction research. Accordingly, a wide range of sample sizes has been suggested, including a minimum sample size of 35 data points, 50 data points, and 75 data points by Fowler (1995), Sudman (1983), and Converse and Presser (1986), respectively. Thus, the obtained sample size seems to be within the standard ranges used in construction research.

The majority of the participants (over 70%) were either safety practitioners/specialists or safety managers/senior specialists. The remainder of the participants (approximately 30%) were distributed between safety interns, safety directors, safety executives, safety presidents, and so forth, as presented in Table 1. The responding participants equivalently represented general contractors (33 participants, 50.77%) and subcontractors (32 participants, 49.23%). Overall, all regions throughout the U.S. (northeast, west, southwest, midwest, south, and mid-Atlantic) were represented in the survey. The participants were located in 13 different geographical locations throughout the U.S. (12 states and the District of Columbia). Due to the extended contacts of the researchers in North Carolina and the surrounding area, the majority of the responses came from the state of North Carolina (22 responses, which represents approximately 34% of the total responses received). South Carolina came second regarding the number of individuals participating in the questionnaire survey, with 12 responses (18.5%). Nearly 10% of the respondents (six respondents) were located in the state of New Jersey, and 6% of the respondents (four respondents) were located in the District of Columbia. Arizona, California, and Georgia each had two individuals participate in the study. Finally, only one individual participated in the study from the following states: Maryland, Massachusetts, New York, Ohio, Vermont, and Virginia. Table 1 summarizes the demographic information of the survey respondents.

Professional experience is one of the most important factors that guarantee the validity and reliability of the study findings (Karakhan et al., 2021). As shown in Table 1, more than 90% of participants have more than 5 years of professional experience, which increases the level of confidence in the study findings.

5.1 Qualifications of Construction Safety Personnel

To achieve the first research objective and assess whether safety personnel in the construction industry possess the minimum required qualifications, the participants were asked about their education, experience, and any certification(s) they possess. After integrating the data, it was found that all of the surveyed safety personnel obtained the minimum required level of experience needed for safety positions, as reported in the existing literature on the topic. Similarly, most of the participants (86%) possessed the minimum education level recommended by professional organizations and safety associations for their safety positions. Finally, with respect to certification, possessing the required certification varies depending on the position of safety personnel. In contrast, the majority of the surveyed safety practitioners/specialists (72%) possessed the minimum certification recommended for their safety position. However, all the surveyed safety executives/presidents/vice presidents (100%) did not possess the minimum certification level recommended for their position. However, this could be a result of the fact that the safety professional certification programs were not mature several years ago. On average, 42% of the surveyed safety personnel did not possess the recommended certification level determined by professional organizations and safety associations for their safety positions. Table 2 shows the distribution of the possessed qualifications for the surveyed construction safety personnel.

5.2 Impact of Qualifications of Construction Safety Personnel on Safety Performance

To achieve the second research objective, the association between the qualifications of construction safety personnel and safety performance (i.e., TRIRs) was examined. Therefore, the TRIRs of the surveyed construction companies were collected from the participants. Given the sensitivity of the information requested (i.e., injury statistics), only 43% of the surveyed construction safety personnel initially responded to these questions and provided the requested information, yielding 28 responses. To increase the level of participation, another email was sent to the participants who did not provide safety metrics for their organizations, and it was clarified that company names and other personal information would be kept confidential and excluded from the study (i.e., not shared with anyone outside the research team). As a result, an additional five participants provided information about the safety metrics of their organizations, increasing the number of participants to 33. This piece of information can assist in answering the three sub-hypotheses for the second goal of the study.

When examining the association between a response variable (i.e., TRIR) and multiple exploratory variables (i.e., qualifications) needed to test the research hypothesis, multiple linear regression is considered an appropriate analysis method (Cobb et al., 2000). Multiple linear regression analysis is a statistical method that uses several explanatory variables to examine the association and predict the outcome of a response variable. The purpose of multiple linear regression analysis is to model the linear relationship between explanatory (independent) variables and a response (dependent) variable (Cobb et al., 2000). In this case, TRIR is the response variable, and safety qualifications of construction personnel (i.e., education, experience, and certification) are the exploratory variables. Equation (1) shows the multiple linear regression utilized in the present study. The scale of exploratory variables is as follows:

• Certification: 0 for no certification at all and 1 for acquiring certification.
• Education: 0 for no education, 1 for a 2-year program, 2 for a 4-year program, and 3 for a program of 4 years or longer.
• Experience: Years of experience.

TRIR ​= β₀​ + β₁*​Education​ + β₂​*Experience​ + β₃*​Certification (1)

Where:

β₀​ is the intercept (a constant value), and

β_1-3 are the estimates for the explanatory variables.

Accordingly, multiple regression was run to predict TRIR from education, experience, and certification status. There was linearity between the continuous exploratory variable and TRIR. There was also independence of residuals, as assessed by a Durbin-Watson statistic of 1.87. There were no studentized deleted residuals greater than ±3 standard deviations. The assumption of normality was met. Accordingly, the assumptions of the test were all met. Afterward, a regression model was developed, and the results indicated that there is statistically significant evidence that the developed multiple regression model predicted TRIR; F (3, 29) = 6.08, p-value = 0.002, adj. R² = 0.38. The output of the produced multiple linear regression model is presented in Table 3. The output includes information about coefficient estimate (????), standard error (SE), t-statistic, p-value, and confidence interval (CI). Equation 2 numerically expresses the model output.

Based on the regression output, years of experience and certification status added statistically significant results to the prediction, p-value < 0.001. Higher levels of experience of safety personnel and possession of certification are negatively associated with TRIR based on the sample studied. This negative association means that each additional year of experience that construction safety personnel possess is expected to be associated with a 0.068 decrease in TRIR, holding other variables constant (t-statistic = –3.578, p-value = 0.001). Similarly, each additional certification possessed by construction safety personnel is expected to be associated, on average, with a 1.910 decrease in TRIR, holding other variables constant (t-statistic = –2.926, p-value = 0.001). On the other hand, no statistically significant evidence of an association between the level of education of safety personnel (2- and 4-year degree or even higher education) and TRIR was found based on the sample studied (t- statistic = 0.517, p-value = 0.610).

TRIR ​= 4.008​ + 0.197*​Education​ – 0.068​*Experience​ – 1.910*​Certification   (2)

Three research hypotheses were tested using the statistical analysis of the multiple linear regression model. This section of the manuscript describes the findings of the statistical analysis with respect to each hypothesis.

6.1 First Hypothesis: Education vs. Safety Performance

The statistical analysis found no statistical evidence against the null hypothesis (1H_o) that higher levels of education are not associated with improved safety performance on construction projects (t-statistic = 0.517, p-value = 0.610). This means that the null hypothesis (1H_o) cannot be rejected and that, based on the study sample, higher levels of education do not lead to lower TRIR and improved safety performance on construction projects.

6.2 Second Hypothesis: Experience vs. Safety Performance

The statistical analysis found substantial statistical evidence against the null hypothesis (2H_o) that more years of industry experience are not associated with improved safety performance on construction projects (t-statistic = –3.578, p-value = 0.001). This means that the alternative research hypothesis (2H₁) should be accepted instead. The alternative research hypothesis states that more years of experience are associated with lower TRIR and improved safety performance on construction projects.

6.3 Third Hypothesis: Certifications vs. Safety Performance

The statistical analysis found substantial statistical evidence against the null hypothesis (3H_o) that acquiring a safety certificate is not associated with improved safety performance on construction projects (t-statistic = –2.926, p-value = 0.001). This means that the alternative research hypothesis (3H₁) should be accepted instead. The alternative research hypothesis states that acquiring a safety certificate is associated with lower TRIR and improved safety performance on construction projects.

The analysis of the collected responses shows that less than 50% of the surveyed construction safety personnel possess the combined minimum qualifications in terms of education, experience, and certification recommended for their safety positions as determined by ASSP. Concerning education, most of the surveyed safety personnel (86%) possess the minimum education level required. Several of them have higher education levels than the minimum education recommended. Regarding the relevant experience of construction safety personnel, all of the surveyed individuals (100%) possess the minimum experience level for their safety position. As the data suggest, the vast majority of the surveyed safety personnel possess the recommended education and experience levels in alignment with the fact that education and prior experience are key requirements for most safety positions in the construction industry. The percentage of safety personnel who did not obtain the recommended certification level is undesirable, especially for higher safety positions. Overall, 58% of the surveyed construction safety personnel possess the minimum certification level recommended for their safety positions. To provide a perspective, less than one-third of the safety personnel in managerial safety positions (directors, executives, presidents, etc.) possess one of the recommended safety certifications. Safety certification and licensure are often obtained during professional development offered by the hiring organization. Professional development opportunities related to safety are sometimes underutilized in the construction industry, especially for small- and medium-sized organizations, due to the limited financial and non-financial resources (Al-Bayati, 2021b). Obtaining a professional certification or licensure related to safety is a sign of maturity that can positively influence safety behaviors and outcomes of construction projects (Gambatese, 2019). These results may suggest that the industry emphasizes experience over other qualifications.

On the other hand, the statistical analysis using multiple linear regression indicates mixed findings. While statistically significant evidence of association is detected between experience level and certification possession of safety personnel and their corresponding companies’ TRIRs, no statistical evidence of an association between the education level of safety personnel and TRIR is observed, according to the regression outputs. The statistical association between the experience level of safety personnel and TRIR is found to be negative, leading to an average of 0.068 potential decreases in TRIR for each additional year of experience safety personnel possess, assuming that education and certification levels remain constant (β₂ = –0.068, SE = 0.382, 95% CI = –0.107 to –0.029, t-statistic = –3.578, p-value = 0.001). This finding is in line with previous studies that found a statistical relationship between years of experience and safety performance on construction projects (Awolusi et al., 2017; Jaselskis et al., 1996). Similarly, the regression model reveals a statistically significant negative association between the certification level of safety personnel and TRIR. To be specific, each additional certification acquired by construction safety personnel is expected to be associated, on average, with a 1.910 reduction in TRIR, assuming that experience and education levels remain constant (β₃ = –1.910, SE = 0.653, 95% CI = –3.245 to –0.575, t-statistic = –2.926, p-value = 0.001). Ideally, all safety personnel should have a certification (Hinze et al., 2013). The finding highlights the importance of safety certifications. However, the industry doesn’t seem to acknowledge the necessity of having the recommended safety certifications, according to the majority of participants who did not possess the recommended level of certifications. Safety certification has multiple benefits, including encouraging safety personnel to continue professional development and learning safety best practices for mitigating and managing workplace hazards. However, it should be acknowledged that sponsoring and providing opportunities to obtain and maintain professional licensing and certification require financial and non-financial resources, which may not be available for smaller construction firms (Al-Bayati, 2021a).

Startlingly, the regression analysis indicates no statistically significant evidence of association between the level of education acquired by safety personnel and TRIR (β₁ = 0.197, SE = 0.653, 95% CI = –0.584 to 0.980, t-statistic = 0.517, p-value = 0.610). This finding could be explained by the fact that students receive a wide range of topics through their educational programs, which may not be related to their specific duties. However, experience and certifications are often related to the daily duties of safety personnel. It should be noted that this surprising finding could be attributed to the fact that all 33 surveyed safety personnel who provided information about their companies’ TRIR possessed the minimum education level recommended for their safety position. This means that the regression analysis did not examine whether not having the required education level is associated with different TRIR—basically, only the impact of having different levels of education that exceed the minimum level on TRIR was tested in the regression analysis. Ideally, the impact of not having the minimum education level recommended on TRIR should be understood within its statistical meaning, not practical implications. The statistical results reveal that having higher levels of education than the minimum recommended level is not statistically always associated with reduced TRIR. However, it is not practical to totally ignore the positive influence of educated safety personnel on overall site safety. On the other hand, it should be clarified that the correlation between education and TRIR does not necessarily express a cause-and-effect relationship. Instead, this correlation may be attributed to multiple contributing factors that cause increased TRIRs on construction projects.

The current study contributes to the body of knowledge by providing exclusive insights into the role of different elements of the desired qualifications for construction safety personnel. Despite its merit, this study has several limitations. First, the sample size of 65 safety personnel was sufficient enough for statistical data analysis. However, larger sample sizes can provide a broader perspective on the distribution of safety personnel qualifications in the U.S. Second, only 33 (i.e., 51%) of surveyed participants provided their companies’ TRIRs. Increasing the number of participants who voluntarily provide TRIR information can shed more light on the subject matter. Third, the analysis presented in this study has mixed levels. Namely, the independent variables (i.e., qualifications of safety personnel) are for the individual survey participants, whereas the dependent variable (i.e., TRIR) is for the survey participants’ firms. To avoid having mixed levels of analysis, future researchers are advised to measure the extent to which all safety personnel in the firm meet the recommended ASSP safety qualifications. Fourth, the TRIR scores were analyzed in aggregate, whereas the survey sample included individuals with different levels of responsibility and professional qualifications. There may be a relationship between one type of qualification and TRIR, but it was masked by aggregating the different levels of responsibility. Fifth, the findings of the present study are limited to the U.S. construction industry and cannot be generalized across other countries. Each country has unique work environments, rules, regulations, incident reporting, recording criteria, culture, weather conditions, etc., and it is unrealistic to generalize the findings of a study conducted in a country across other nations. Sixth, the adjusted R² for the overall model was 38%, a moderate size effect, according to Cohen (1988). Construction safety scholars are encouraged to address these critical limitations to improve the industry’s understanding of the necessary safety practitioner qualifications.

In addition, TRIR was considered the only measurement of a company’s safety outcome, which may not fully represent the safety performance of a company (Al-Bayati et al., 2020). Future studies must consider other leading indicators to investigate the role of safety personnel qualifications in improving safety performance in their companies. It is also recommended that future research examines the impact of designating safety personnel for each construction site, given its size and characteristics, on the overall TRIR. The impact of a different safety-officer-to-employee-ratio on the safety performance of a project should be studied as well.

Construction as a profession suffers from high rates of incidents in the workplace. However, most of these incidents, specifically severe incidents, can be prevented by implementing an effective safety plan. Safety personnel play a key role in the successful development and implementation of safety plans. There is scarce research on the role of effective safety personnel qualifications in enhancing construction safety performance. The present research study aimed to assess the qualifications of safety personnel in the construction industry and examine the association between the qualifications of safety personnel and overall construction site safety. Among others, the study revealed a lack of significant association between TRIR and education, which is a concerning finding that requires further investigation and special attention from related safety educational programs. On the other hand, the study suggests a negative correlation between TRIR and construction safety experience, as well as related safety certifications possessed by safety personnel. Despite  its importance and its role in preventing accidents, there is a lack of certification attainment among safety personnel in the construction industry in general and upper safety positions. Attaining the required certification for all safety positions is critical. The finding of this study revealed a statistically significant association between certification attainment and TRIRs on construction projects. Construction organizations are recommended to consider certification attainment as one of the critical requirements when hiring safety personnel. In addition, construction firms should sponsor and provide opportunities for safety personnel to obtain and maintain professional safety certification. Although such sponsorship might be costly upfront, the benefits of acquiring a safety certification are expected to outweigh any cost spent. Finally, project owners should incorporate a requirement of certifications for safety personnel handling construction projects due to the importance of these certifications in improving the safety performance of construction projects.

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