Evaluating road work site safety management: A case study of the Amman bus rapid transit project construction

Figures & data

Figure 1. A typical work zone layout (Sharma et al., 2017).

Table 1. Items describing assessed measures on work -zone by category and location and Safety Climate (SC) factors

Category:	Item No.	General Traffic	Category	Item No.	Within the Site
		Measure Description			Measure Description
SC1: Supervision, guidance, inspection:General Site	Q1	Suitable routes are provided for traffic and pedestrian	SC2 Education &Training: Staff Training	Q1	Drivers/employees gone through safety induction course
	Q2	Skid resistance surface are provided		Q2	Drivers/employee going through refresher training
	Q3	Vehicle traffic is separated from Pedestrian traffic		Q3	Drivers have a valid license and experience to operate the construction vehicle.
	Q4	Traffic Control devices are installed according to TMP		Q4	Flagmen been trained to guide the transport vehicles?
	Q5	Adequate Street lighting for all road users	SC3 Safety Rules: Traffic Operation	Q1	Appropriate transport vehicles are provided for the job?
	Q6	Road surface is even and stable to withstand heavy vehicles		Q2	Drivers’ compliance with regulatory laws is monitored
	Q7	Routes for transport vehicles and pedestrian walkways kept free from hazard objects		Q3	Site staff and workers wear safe outfit (e.g., visibility vests)
	Q8	Traffic routes properly marked		Q4	Drivers perform pre-operating tests before the actual operation
	Q9	Signs installed where required		Q5	Staff/workers evacuated from the areas before allowing powered vehicle to
	Q10	Other safety measures are provided (mirrors, rumble strips, etc)		Q6	Flagmen provide to guide the maneuvering of transport vehicles
	Q11	Designated traffic routes are wide enough		Q7	Flagmen position themselves at a safe position?
	Q12	Pedestrian pathways are wide enough		Q8	Vehicle properly parked talking all necessary precautions
SC1: Supervision, guidance, inspection: Maintenance & Management	Q1	Roads and walkways suitable and maintained for vehicular and pedestrian types and volumes	SC4 Safety Procedures: Loading & Unloading Activities	Q1	Loading or unloading operations conducted a way from traffic and pedestrians?
	Q2	Adequate Separation maintained between vehicles and pedestrians		Q2	Appropriate vehicle(s) used for loading or unloading
	Q3	Adequate parking places are provided and maintained to meet the demand		Q3	Loading or unloading activities conducted on flat, stable, and firm ground free from potholes
	Q4	Sufficient lighting level for vehicular and pedestrian traffic is provided		Q4	Parking brakes are applied to prevent hazardous movement (when coupling vehicles)
	Q5	Motorized vehicle traffic routes have firm and even surfaces that are well maintained.		Q5	Vehicles’ drivers used brakes and/or stabilizer to prevent unsafe movements during loading and unloading operations?
	Q6	Vehicular and pedestrian routes are kept free of hazards and obstructions		Q6	Lifting equipment, equipment or gears used for unloading vehicles possess valid legal inspection certificate (s)?
	Q7	Traffic route designed and maintained to avoid sharp or blind turns		Q7	Loading or unloading conducted by spreading load evenly to avoid vehicle instability
	Q8	Traffic route marking is correctly maintained according to traffic management plan (TMP)		Q8	Checks are made to ensure that loading is secured and no overloading before the permitting the vehicle to leaves the site
	Q9	Standard Traffic Control devices are installed and kept well where required		Q9	There is noticeable unsafe practice during loading and loading activities
	Q10	Convex mirror, road humps, or safety barriers are provided and supported where necessary		Q10	Employees follow safe work procedures when (un)coupling, (un)loading and securing loads?
	Q11	Pedestrian pathways are maintained wide enough	SC5 Management Commitment to safety Site Administration	Q1	Workplace traffic rules documented and distributed?
				Q2	Staff, workers, and visitors are aware of the workplace traffic rules
				Q3	Risk assessment conducted for work activities; communicated to all concerned personnel prior to operation
				Q4	Relevant actions are taken when the workplace’s traffic rules (if any) are violated

Figure 2. Amman BRT and Amman-Zarqa BRT link layout.

Figure 3. Safety measures assessment in work zones: sites 1–4 for investigated safety factors.

Figure 4. A flow chart of the Research methods.

Table 2. Sample characterises

Group	Factor	Categories and Valid Response Percentage						Valid Percentage	Response rate
Project-Based	Gender	Female	Male					54 Cases	72.0%
		31.5%	68.5%
	Age	<30	30–39	40–49	50–70			74 Cases	98.7%
		39.2%	28.4%	17.6%	14.9%
	Representation Side	Consultant	Contractor	Project Owner				42 cases	56.0%
		28.6%	40.5%	31.0%
	Education Level	PhD	MSc	BSc	Associate degree	High School	Basic School	68 cases	90.7%
		1.5%	29.4%	61.8%	1.5%	2.9%	2.9%
	Professional Category	Project Director	Resident Engineer	Site Engineer	Supervisor	Labour		68 cases	90.7%
		10.3%	41.2%	14.7%	13.2%	20.6%
	Years of experience	1–3	4–6	7–10	10–15	<15		64 cases	85.3%
		26.6%	14.1%	20.3%	14.1%	25.0%
General-Based	Gender	Female	Male					43 Cases	100%
		27.9%	72.1%
	Age	<30	30–39	40–49	50–70			43 Cases	100%
		20.9%	37.2%	16.3%	25.6%
	Representation Side	Consultant	Contractor	Project Owner				43 Cases	100%
		32.6%	27.9%	39.5%
	Education Level	PhD	MSc	BSc	Associate degree	High School	Basic School	43 Cases	100%
			25.6%	67.4%	7.0%
	Professional Category	Project Director	Resident Engineer	Site Engineer	Supervisor	Labour		43 Cases	100%
		39.5%	16.3%	23.3%	7.0%	2.3%
	Years of experience	1–3	4–6	7–10	11–15	<15		43 Cases	100%
		11.6%	11.6%	23.3%	16.3%	37.2%

Figure 5. The application rate for measures of the investigated safety factors measures enhancing safety within the site of the project and its surrounding by respondent group.

Figure 6. The application rate for measures of the investigated measures of safety factors enhancing safety within the site of the project and its surrounding by respondent group.

Table 3. Reliability test result for each safety factor measures group by respondent group (Cronbach Alpha coefficients)

Group	GS		ST		TO		LU		SA		MM		General Traffic		Within the site		Overall
Group Based	PB	GB	PB	GB	PB	GB	PB	GB	PB	GB	PB	GB	PB	GB	PB	GB	PB	GB
	0.94	0.95	0.96	0.83	0.96	0.95	0.92	0.94	0.84	0.83	0.83	0.96	0.97	0.97	0.98	0.97	0.99	0.98
Both Groups	0.94		0.89		0.95		0.93		0.83		0.93		0.97		0.99		0.99

Figure 7. The perception of appropriateness of application for measures of the investigated measures of safety factors enhancing safety within the site of the project and its surrounding by respondent group.

Table 4. Evaluation of road safety measures’ applicability in work zones, considering safety factors and subject sociodemographic variables (average of all responses for each factor)

Factors	Item and Statistical Test	Within the Site Safety Factor	General Traffic Safety Factor	Overall Safety Factor	General Site	Maintenance & Management	Staff Training	Traffic Operation	Loading & unloading	Site Administrat-ion
Site Number	1	3.826	3.584	3.776	3.835	3.456	3.83	3.902	3.00	3.607
	2	3.244	3.26	3.26	3.239	3.343	3.18	3.217	3.187	3.396
	3	3.876	3.462	3.733	3.807	3.198	3.8	3.916	4.011	3.875
	4	4.274	3.964	4.076	3.833	3.529	4.4	4.371	3.926	4.4
	5	3.498	3.34	3.416	3.13	3.372	3.31	3.468	3.677	3.541
	F-Value, Sig	3.71, <.001	2.74, 0.032	4.64, 0.002	4.58, 0.002	0.395,0.812	6.22, 0.00	5.76, <0.001	3.31, 0.013	4.48, 0.002
Age Group	<30	3.996	3.362	3.848	3.778	3.36	3.99	4.176	3.852	3.863
	30–39	3.595	3.59	3.558	3.547	3.44	3.50	3.46	3.597	3.632
	400–49	3.894	3.50	3.797	3.847	3.365	3.98	3.893	3.706	4.00
	50–70	3.718	3.67	3.675	3.638	3.464	3.94	3.789	4.034	3.95
	F-Value, Sig	1.93, 0.11	0.67, 0.618	1.68, 0.159	3.21, .016	0.04. 0.997	2.41, 0.054	3.06, 0.02	0.614. 0.64	0.79, 0.534
Experience Group	1–3	3.808	3.494	3.665	3.291	3.264	3.81	3.845	3.81	3.73
	4–6	3.653	3.304	3.536	3.515	3.079	3.46	3.734	3.683	3.5
	7–10	3.494	3.417	3.491	3.49	3.519	3.34	3.381	3.556	3.629
	11–15	3.755	3.612	3.654	3.435	3.51	3.69	3.768	3.752	3.685
	>15	3.80	3.636	3.704	3.457	3.44	3.85	3.883	3.803	3.827
	F-Value, Sig	0.51,0.769	0.54, 0.747	0.29, 0.92	0.18, 0.969	0.64, 0.669	1.055, 0.39	0.89, 0.49	0.357, 0.877	0.45, 0.814
Job on Site	Worker	2.988	2.885	2.998	2.978	3.087	2.52	3.214	3.003	4.25
	Forman	3.769	3.381	3.633	3.424	3.24	3.52	3.792	3.829	2.883
	Site Engineer	3.841	3.568	3.742	3.646	3.403	3.79	3.895	3.885	3.683
	Liaison Engineer	3.988	3.763	3.906	3.866	3.619	3.91	3.783	4.075	3.881
	Resident Engineer	3.525	3.38	3.434	3.248	3.319	3.46	3.491	3.556	4.185
	Project Director	3.73	3.565	3.626	3.439	3.454	3.68	3.771	3.675	3.657
	F-Value, Sig	2.56,0.024	1.88, 0.09	2.34, 0.037	1.57, 0.162	0.48, 0.824	2.91, 0.012	1.14, 0.435	2.61, 0.021	2.59, 0.023
Education Level	High School	2.167	2.636	2.254	2.083	2.772	2.5	2.625	1.667	1.667
	High School	3.177	3.076	3.331	3.458	3.818	2.33	3.679	3.406	3.406
	Associate	3.098	3.084	3.111	3.167	3.105	3.06	3.031	3.425	3.425
	BSc	3.751	3.538	3.665	3.55	3.415	3.7	3.758	3.781	3.781
	MSc	3.871	3.609	3.736	3.498	3.449	3.77	3.906	3.9	3.9
	PhD	3.613	3.2	3.452	3.9	2.4	4	3.75	2.95	2.95
	F-Value, Sig	2.33,0.037	0.954, 0.46	1.91, 0.086	1.12, 0.354	0.87, 0.517	1.653, 0.14	1.265, 0.28	4.09, 0.001	2.46, 0.03
Representative	Consultant	3.508	3.34	3.466	3.335	3.302	3.37	3.538	3.546	3.398
	Contractor	3.449	3.319	3.386	3.22	3.283	3.33	3.53	3.563	3.351
	Owner	3.72	3.619	3.623	3.448	3.48	3.76	3.703	3.706	3.821
	F-Value, Sig	4.65,0.004	1.53, 0.212	3.76, 0.013	3.46, 0.019	0.372, 0.773	3.08, 0.031	2.44, 0.069	2.25, 0.087	7.31, <.001
Group	PB	3.834	3.587	3.834	3.695	3.387	3.84	3.84	3.747	3.861
	GB	3.498	3.34	3.498	3.13	3.372	3.31	3.31	3.677	3.541
	t-value, Sig	2.29,0.012	1.51, 0.068	2.29, 0.012	3.45, <.001	−1.995, 0.027	2.79, 0.003	2.41, 0.009	0.47, 0.319	1.82, 0.036
Gender	Male	3.572	3.402	3.572	3.343	3.315	3.49	3.558	3.596	3.619
	Female	3.852	3.602	3.852	3.592	3.592	3.70	3.859	3.921	3.875
	t-value, Sig	−1.58, 0.059	−1.06, 0.145	−1.58, 0.059	−1.19, 0.118	−1.08, 0.143	−0.91, 0.183	−1.45, 0.076	−1.86, 0.033	−1.22, 0.112
Location	Urban	3.692	3.466	3.692	3.515	3.313	3.64	3.715	3.658	3.714
	Rural	3.8	3.642	3.8	3.329	3.718	3.57	3.796	4.021	3.816
	t-value, Sig	−0.499, 0.311	−0.88, 0.189	−0.55, 0.584	0.83, 0.204	−1.995, 0.027	0.298, 0.383	−0.53, 0.363	−1.92, 0.029	−0.45, 0.328

Table 5a. Factor Analysis Displays Component Loading for each Safety Factor: General Traffic

Factor	Safety Item	Route & Stability (F1)	Control Device & Pedestrian (F2)
General Site	GS 1	0.872	0.256
	GS 2	0.805	0.276
	GS 3	0.815	0.359
	GS 4	0.817	0.354
	GS 5	0.763	0.236
	GS 6	0.846	0.181
	GS 7	0.672	0.532
	GS 8	0.233	0.861
	GS 9	0.176	0.870
	GS 10	0.270	0.884
	GS 11	0.441	0.713
	GS 12	0.412	0.666
	Eigenvalue	5.01	4.0
	Explained Variance (%)	41.77	33.32
	Cumulative Explained (%)	75.06
Maintenance and Management	Safety Item	Traffic Management (F1)	Control Device (F2)
	MM 1	0.864	0.292
	MM 2	0.809	0.367
	MM 3	0.885	0.185
	MM 4	0.931	0.091
	MM 5	0.517	0.627
	MM 6	0.911	0.174
	MM7	0.812	0.217
	MM8	0.166	0.900
	MM9	0.135	0.867
	MM10	0.156	0.841
	MM11	0.281	0.791
	Eigenvalue	4.96	3.63
	Explained Variance (%)	45.06	32.96
	Cumulative Explained (%)	78.02

Table 5b. Factor Analysis Displays Component Loading for each Safety Factor: Within the Site

Factor	Safety Item	Staff Training (F1)	Factor	Safety Item	Operation Control (F1)	Safe Operations (F2)
Staff Training	ST 1	0.922	Loading and unloading	LU 1	0.813	0.432
	ST 2	0.896		LU 2	0.865	0.253
	ST 3	0.794		LU 3	0.890	0.280
	ST 4	0.862		LU 4	0.847	0.327
	Eigenvalue	3.03		LU 5	0.810	0.263
	Explained Variance (%)	75.68		LU 6	0.290	0.831
Traffic Operations	Safety Item	Traffic Operation (F1)		LU 7	0.622	0.613
	TO 1	0.751		LU 8	0.363	0.723
	TO 2	0.765		LU 9	0.269	0.765
	TO 3	0.896		LU 10	0.187	0.83
	TO 4	0.904		Eigenvalue	4.29	3.30
	TO 5	0.882		Explained Variance (%)	42.86	32.98
	TO 6	0.912		Cumulative Explained (%)	75.84
	TO 7	0.904
	TO 8	0.902
	Eigen value	6.0
	Explained Variance %	75.09
Site Administration	Safety Item	PB (F1)
	SA 1	0.890
	SA 2	0.876
	SA 3	0.689
	SA 4	0.816
	Eigen value	2.7
	Explained Variance (%)	67.51

Table 6a. Explanatory Factor Analysis: Component Loading for each Factor by respondent Category and safety factor: General Traffic

Factor	Group	PB		GB
	Safety Item	Route & Stability (F1)	Control Device & Pedestrian (F2)	Control Device & Pedestrian (F1)	Control Device & Pedestrian (F1)
General Site	GS 1	0.886	0.120	0.422	0.833
	GS 2	0.844	0.267	0.295	0.851
	GS 3	0.952	0.138	0.756	0.455
	GS 4	0.960	0.145	0.772	0.428
	GS 5	0.941	0.196	0.383	0.566
	GS 6	0.910	0.237	0.169	0.872
	GS 7	0.578	0.642	0.506	0.737
	GS 8	0.111	0.951	0.659	0.417
	GS 9	0.078	0.967	0.672	0.358
	GS 10	0.065	0.950	0.870	0.311
	GS 11	0.481	0.713	0.891	0.206
	GS 12	0.478	0.659	0.759	0.223
	Eigenvalue	5.855	4.245	4.88	3.924
	Explained Variance (%)	48.8	35.38	40.62	32.7
	Cumulative Explained (%)	84.14		73.3
Maintenance and Management	Group	PB		GB
	Safety Item	Traffic Management (F1)	Control Device (F2)	Maintenance and Control (F1)	Traffic Management (F2)
	MM 1	0.861	0.165	0.776	0.54
	MM 2	0.734	0.494	0.506	0.744
	MM 3	0.954	0.09	0.502	0.735
	MM 4	0.898	-.004	0.619	0.633
	MM 5	0.348	0.797	0.861	0.311
	MM 6	0.952	0.184	0.562	0.665
	MM7	0.895	0.112	0.798	0.356
	MM8	-0.494	0.793	0.765	0.418
	MM9	-0.534	0.811	0.909	0.179
	MM10	-0.341	0.911	0.155	0.884
	MM11	-0.005	0.929	0.271	0.804
	Eigenvalue	5.38	4.03	4.70	4.09
	Explained Variance (%)	48.94	36.63	42.7	37.2
	Cumulative Explained (%)	85.57		79.9

Table 6b. Explanatory Factor Analysis: Component Loading for each Factor by respondent Category and safety factor: Within-the-Site

Factor	Group		PB				GB
	Safety Item		Staff Training (F1)				Staff Training (F1)
Staff Training	ST 1		0.952				0.902
	ST 2		0.965				0.860
	ST 3		0.935				0.676
	ST 4		0.923				0.811
	Eigenvalue		3.57				2.68
	Explained Variance (%)		89.13				66.7
Traffic Operations			PB				GB
			Operation				Operation
	TO 1		0.763				0.756
	TO 2		0.836				0.718
	TO 3		0.925				0.885
	TO 4		0.929				0.897
	TO 5		0.963				0.846
	TO 6		0.907				0.919
	TO 7		0.919				0.907
	TO 8		0.930				0.890
	Eigen value		6.46				5.85
	Explained Variance (%)		80.76				73.13
Loading & Unloading Activities	Group	PB					GB
	Safety Item	Safe Operations (F1)			Operation Control (F2)	Safe Practice (F3)	Operation Control (F1)	Safe Operations (F2)
	LU 1	0.901			0.314	0.023	0.347	0.842
	LU 2	0.890			0.331	0.031	0.255	0.859
	LU 3	0.942			0.156	0.142	0.325	0.891
	LU 4	0.943			0.175	0.131	0.576	0.627
	LU 5	0.810			0.014	0.547	0.659	0.509
	LU 6	0.382			0.771	0.227	0.895	0.168
	LU 7	0.602			0.684	0.074	0.793	0.444
	LU 8	0.527			0.489	-0.290	0.823	0.267
	LU 9	0.121			0.287	0.885	0.776	0.422
	LU 10	-0.002			0.884	0.213	0.710	0.403
	Eigen value	4.84			2.43	1.31	4.27	3.53
	Explained Variance (%)	48.4			24.3	13.07	42.71	35.3
	Cumulative Explained (%)	85.8					78.01
Site Administration	Group			PB			GB
	Safety Item			Site Administration (F1)			Site Administration (F1)
	SA 1			0.945			0.839
	SA 2			0.924			0.853
	SA 3			0.617			0.734
	SA 4			0.765			0.846
	Eigen value			2.71			2.69
	Explained Variance (%)			67.80			67.18

Table 7. The impact of sociodemographic factors on the extracted factors: the entire data set

Factor	Site	Group	Location	Gender	Age	Education	Experience	Representativeness	Job
	F-value, sig	t-value, sig	t-value, sig	t-value, sig	F-value, sig	F-value, sig	F-value, sig	F-value, sig	F-value, sig
Route & Stability (F1)	3.08, 0.034	0.86, 0.396	−0.52, 0.605	−0.81, 0.423	0.64, 0.593	2.35, 0.043	1.50, 0.206	0.92, 0.438	1.18, 0.329
Control Device & Pedestrian (F2)	2.22, 0.095	0.24, 0.814	−0.42, 0.676	0.26, 0.795	0.26, 0.856	1.19, 0.325	0.99, 0.435	0.63, 0.598	0.65, 0.665
Staff Training (F1)	3.37, 0.014	1.33, 0.188	−0.53, 0.597	−0.40, 0.694	1.47, 0.229	1.84, 0.104	1.57, 0.179	1.65, 0.187	3.47, 0.005
Traffic Operation (F1)	0.79, 0.539	−0.46, 0.648	−1.94, 0.057	−0.94, 0.353	2.40, 0.078	0.91, 0.495	0.91, 0.483	0.16, 0.921	1.08, 0.79
Safe Operations (F1)	3.41, 0.024	−1.78, 0.093	−2.20, 0.032	−0.65, 0.520	1.48, 0.230	9.13, 0.000	0.79, 0.559	0.17, 0.918	5.84, 0.000
Operation Control (F2)	0.57, 0.638	1.10, 0.276	−1.29, 0.202	−1.23, 0.222	0.92, 0.435	2.60, 0.028	0.38, 0.863	0.22, 0.885	0.70, 0.625
Site Administration (F1)	1.63, 0.178	1.14, 0.260	−0.97, 0.336	−1.40, 0.168	0.60, 0.619	1.81, 0.112	0.14, 0.983	2.94, 0.040	2.01, 0.090
Traffic Management (F1)	5.99, 0.001	1.14, 0.246	−1.00, 0.321	−0.07, 0.943	2.60, 0.062	0.47, 0.757	2.62, 0.034	0.85, 0.472	0.996, 0.429
Control Device (F2)	15.47, 0.000	−0.51, 0.619	−1.69, 0.097	−0.96, 0.342	1.07, 0.371	0.51, 0.728	3.03, 0.018	1.46, 0.235	1.19, 0.325

Table 8. The impact of sociodemographic factors on the extracted factors by respondent Group

Group	Reduced Factor	sociodemographic factors
		Site	Location	Gender	Age	Education	Experience	Representativeness	Job
		F-value, sig	t-value, sig	t-value, sig	F-value, sig	F-value, sig	F-value, sig	F-value, sig	F-value, sig
Project-Based	Route & Stability (F1)	2.52, 0.110		−0.96, 0.354	0.33, 0.805	1.95, 0.149	1.01, 0.450	0.25, 0.859	1.13, 0.388
	Control Device & Pedestrian (F2)	1.52, 0.247		0.85, 0.413	0.10, 0.960	0.35, 0.875	1.12, 0.395	0.51, 0.681	0.48, 0.783
	Staff Training (F1)	3.40, 0.031		−0.36, 0.725	0.70, 0.562	2.46, 0.060	1.51, 0.223	1.20, 0.326	3.24, 0.017
	Traffic Operation (F1)	0.80, 0.514		−1.76, 0.101	1.77, 0.198	0.44, 0.810	0.29, 0.908	0.09, 0.967	0.43, 0.819
	Safe Operations (F1)	0.61, 0.560		−2.03, 0.070	0.46, 0.640	11.84, 0.001	1.85, 0.191	0.30, 0.828	5.59, 0.010
	Operation Control (F2)	1.81, 0.202		−0.72, 0.489	2.33, 0.136	4.26, 0.025	0.40, 0.840	1.40, 0.291	0.29, 0.909
	Safe Practice (F1)	0.10, 0.908		−0.73, 0.481	0.92, 0.424	0.74, 0.61	0.77, 0.593	6.16, 0.009	0.48, 0.784
	Site Administration (F1)	1.54, 0.235		−1.50, 0.151	0.36, 0.782	2.18, 0.099	0.60, 0.699	1.97, 0.149	0.95, 0.469
	Traffic Management (F1)	2.38, 0.132		0.00, 0.998	1.12, 0.380	0.18, 0.906	3.58, 0.042	0.01, 0.998	1.74, 0.211
	Control Device (F2)	10.10, .002		−0.92, 0.379	1.25, 0.335	1.05, 0.407	1.29, 0.331	3.01, 0.072	0.11, 0.975
General-Based	Control Device & Pedestrian (F1)		−0.87, 0.389	−0.21, 0.832	0.51, 0.678	2.54, 0.091	0.10, 0.982	0.51, 0.604	0.61, 0.691
	Route (F2)		−0.84, 0.407	−0.35, 0.727	0.37, 0.772	0.28, 0.759	0.67, 0.615	0.20, 0.817	1.13, 0.362
	Staff Training (F1)		−1.56, 0.127	−0.19, 0.853	0.80, 0.502	1.17, 0.322	1.33, 0.276	0.70, 0.500	1.83, 0.130
	Traffic Operation (F1)		−2.03, 0.048	−0.09,0.93	1.01, 0.399	1.20, 0.311	0.82, 0.522	0.14, 0.872	2.03, 0.098
	Operation Control (F1)		−1.33, 0.190	−1.01, 0.319	1.01, 0.399	1.13, 0.334	0.40, 0.805	0.28, 0.755	2.02, 0.098
	Safe Operations (F2)		−2.15, 0.037	0.87, 0.388	1.73, 0.176	0.35, 0.709	0.49, 0.741	2.29, 0.115	0.79, 0.567
	Site Administration (F1)		−1.90, 0.065	−0.72, 0.476	0.57, 0.641	0.95, 0.397	0.32, 0.861	1.71, 0.195	1.94, 0.111
	Traffic Management & Maintenance (F1)		−1.48, 0.147	−0.99, 0.328	2.59, 0.066	0.20, 0.822	1.24, 0.312	1.27, 0.291	0.90, 0.492
	Safety Measures (F2)		−1.61, 0.114	0.53, 0.598	0.36, 0.782	2.38, 0.105	1.26, 0.304	0.10, 0.901	0.98, 0.446

Table 9. Correlation matrix for observed and extracted variables by respondent group

Table 10. CFA results for the 1^st and 2^nd order Models

Latent Variable	Observed/latent Variable	1^st Order Model		2^nd Order Model		Latent Variable Estimate	Observed Variable	1^st Order Model		2^nd Order Model
		Estimate	Sig (p-value)	Estimate	Sig (p-value)			Estimate	Sig (p-value)	Estimate	Sig (p-value)
General Traffic	General Site			0.958	<.0001	Staff Training	ST1	0.949	<.0001	0.953	<.0001
	Maintenance & Monitoring			0.967	<.0001		ST2	0.957	<.0001	0.962	<.0001
Within the Site	Staff Training			0.984	<.0001		ST3	0.840	<.0001	0.857	<.0001
	Traffic Operation			0.974	<.0001		ST4	0.917	<.0001	0.925	<.0001
	Loading & unloading			0.91	<.0001	Traffic Operation	TO1	0.872	<.0001	0.867	<.0001
	Site Administration			0.954	<.0001		T02	0.842	<.0001	0.839	<.0001
General Site	GS1	0.937	<.0001	0.935	<.0001		TO3	0.945	<.0001	0.942	<.0001
	GS2	0.884	<.0001	0.879	<.0001		TO4	0.951	<.0001	0.955	<.0001
	GS3	0.955	<.0001	0.952	<.0001		TO5	0.938	<.0001	0.942	<.0001
	GS4	0.935	<.0001	0.934	<.0001		TO6	0.953	<.0001	0.957	<.0001
	GS5	0.903	<.0001	0.897	<.0001		TO7	0.931	<.0001	0.936	<.0001
	GS6	0.898	<.0001	0.889	<.0001		TO8	0.938	<.0001	0.935	<.0001
	GS7	0.909	<.0001	0.899	<.0001	Loading & unloading	LU1	0.958	<.0001	0.959	<.0001
	GS11	0.899	<.0001	0.892	<.0001		LU2	0.924	<.0001	0.926	<.0001
	GS12	0.818	<.0001	0.799	<.0001		LU7	0.909	<.0001	0.785	<.0001
	MM1	0.949	<.0001	0.942	<.0001		LU3	0.770	<.0001	0.913	<.0001
Maintenance & Management	MM2	0.912	<.0001	0.901	<.0001	Site Administration	SA1	0.977	<.0001	0.978	<.0001
	MM3	0.949	<.0001	0.942	<.0001		SA2	0.937	<.0001	0.934	<.0001
	MM4	0.973	<.0001	0.968	<.0001		SA3	0.843	<.0001	0.842	<.0001
	MM5	0.854	<.0001	0.835	<.0001		SA4	0.946	<.0001	0.945	<.0001
	MM6	0.921	<.0001	0.912	<.0001
	MM7	0.831	<.0001	0.817	<.0001
Models’ Goodness of Fit
		1st Order Model		2nd Order Model				1st Order Model		2nd Order Model
CMIN	CMIN/DF	2.591		2.618		Baseline Comparisons	NFI	0.592		0.582
	Sig (p-value)	0		0			IFI	0.703		0.693
RMSEA		0.082		0.083			TLI	0.649		0.643
							CFI	0.694		0.685

Figure 8. SEM model: 1^st order model-six latent variables and thirty-six observed variables.

Figure 9. SEM model: 2^nd order model - eight latent variables and thirty-six observed variables.

Sharma, A., Huang, T., Roy, S., & Savolainen, P. T. (2017). Setting work zone speed limits. Centre for Transportation Research and education and smart work zone Development initiative. Institute for Transportation. Iowa State University. Final Report.

 Google Scholar