The Physiological Experimental Study on the Effect of Different Color of Safety Signs on a Virtual Subway Fire Escape—An Exploratory Case Study of Zijing Mountain Subway Station
Abstract
:1. Introduction
2. Materials and Methods
2.1. Case Study
2.2. Virtual Scene Settings
- (1)
- The design of four different color combinations of safety signs
- (2)
- The illumination and brightness Settings
- (3)
- Moving speed Setting
- (4)
- Other Settings
2.3. Participants
2.4. Apparatus
2.5. Experiment Design and Procedure
2.6. Variables
3. Results and Discussion
3.1. Relationship between Color_of_Safety_Sign and Escape Performance
3.2. Relationship between Color_of_Safety_Sign and Eye-Tracking Indicators
3.3. Relationship between Color_of_Safety_Sign and Physiological Indicators
- (1)
- Change of physiological indicators during virtual escape vs. baseline
- (2)
- Relationship between Color_of_safety_sign and SC, HR
3.4. Limitations
- (1)
- Virtual scene
- (2)
- Participants
- (3)
- Single case study
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Standard Name | Standard No. | Notes |
---|---|---|
Fire Safety Signs-Part 1: Signs [38] | GB 13495.1-2015 | China National Standard |
The Passenger Service Signs for Urban Rail Transit [39] | GB/T 18574-2008 | China National Standard |
Safety Way Guidance Systems-Setting Principles and Requirements [40] | GB/T 23809-2009 | China National Standard |
Safety Signs and Guideline for the Use [41] | GB 2894-2008 | China National Standard |
Safety Colors [42] | GB 2893-2008 | China National Standard |
Standard for Fire Safety and Emergency Symbols [43] | NFPA (National Fire Protection Association) 170-2018 | American National Standard |
Name | Description | |
---|---|---|
Hardware | HTC Vive Pro Eye 2.0 (Hongda Communications Co. LTD, Shanghai, China) | The virtual reality Head-Mounted Display (HMD), containing two 3.5-inch 3K AMOLED displays, each with a resolution of 1440 × 1600, a maximum field of view Angle of 110°, and a screen refresh rate of 90 HZ |
PPG (Photoplethysmography) sensor (Kingfar International Inc., Beijing, China), EDA sensor (Kingfar International Inc., Beijing, China) | The real-time physiological data acquisition device, recording participants’ HR and SC (Skin Conductance) data | |
HTC trackpad (Hongda Communications Co. LTD, Shanghai, China) | Participants moving or making turns with it in the virtual subway fire escape | |
Unity3D VR Plugin data synchronization interface adapter (Kingfar International Inc., Beijing, China) | Data in VR scene were transmitted and recorded synchronously by this device | |
CPU (i5-8400), GPU (GTX 1060) | The computer operating environment in the virtual experiment | |
Software | SketchUp (Version of 2018pro, Trimble, Sunnyvale, CA, USA) | The virtual reality scene model was created by it according to the real subway station of Zijing Mountain in Zhengzhou, China, with 1:1 scale |
Photoshop CS6 (Adobe Systems Incorporated, San Jose, CA, USA) | Some images were designed by it as textures in Unity3D | |
Unity3D (Version of 2019.2.11f1, Unity Technologies, San Francisco, CA, USA) | The created model was imported into it for the interactive setting of scene functions | |
ErgoLAB V3.0 man-machine-environment synchronous cloud platform (Kingfar International Inc., Beijing, China) | This software was used for real-time physiological data acquisition and processing, including ErgoLAB wearable wireless physiological recording module (PPG, EDA) and virtual reality eye movement tracking module (Tobii VR) | |
IBM SPSS Statistic 22 (IBM Corporation, Armonk, NY, USA) | This software was used for data analysis |
Variable Name | Meaning | Unit |
---|---|---|
Total_escape_time | Total time that participants took to escape to the ground exits from the escape starting point in the −4F | s |
Total_travel_distance | Total moving distance that participants travel to escape to the ground exits from the escape starting point in the −4F | m |
AOI_Time_To_First_Fixation | Time to first fixation at the safety sign in AOI (Area of Interest) | s |
AOI_First_Fixation_Duration | The fixation duration time of the first fixation point at the safety sign in AOI | s |
AOI_Total_Fixation_Duration | Total fixation duration time for all the fixation points at the safety signs in AOI | s |
AOI_Fixation_Count | Total fixation number (count) for all the fixation points at the safety signs in AOI | n (number) |
Average_Pupil | The average pupil diameter of left and right eyes during the fixation at all the fixation points at the safety signs in AOI | mm |
increase_rate | The growth rate of the variable during escape vs. baseline | dimensionless |
Mean_SC | The mean of the Skin Conductance during escape or baseline | μs |
Mean_HR | The mean of the Heart Rate during escape or baseline | bpm (beats per minute) |
Color_of_safety_sign | Four different color combinations of safety signs: “Green and black”, “Red and white”, “Yellow and black”, and “Blue and white” | - |
Color_of_Safety_Sign | Total_Escape_Time (Mean ± SD) | Total_Travel_Distance (Mean ± SD) |
---|---|---|
Green and black (n = 24) | 220.8875 ± 69.03976 | 267.3625 ± 61.37007 |
Red and white (n = 24) | 251.9750 ± 85.60563 | 279.3542 ± 94.52431 |
Yellow and black (n = 24) | 247.3250 ± 112.72859 | 300.4417 ± 127.57933 |
Blue and white (n = 24) | 249.7583 ± 114.68886 | 305.9625 ± 130.72830 |
Sig. | 0.66 | 0.567 |
Color_of_safety_sign | AOI_Time_To_First_Fixation (Mean ± SD) | AOI_First_Fixation_Duration (Mean ± SD) | AOI_Total_Fixation_Duration (Mean ± SD) | AOI_Fixation_Count (Mean ± SD) | Average_Pupil (Mean ± SD) |
---|---|---|---|---|---|
Green and black (n = 24) | 46.7446 ± 64.12274 | 0.1917 ± 0.16433 | 1.1063 ± 1.25075 | 6.3333 ± 7.32279 | 4.3167 ± 2.12531 |
Red and white (n = 24) | 41.2896 ± 68.69189 | 0.1908 ± 0.16686 | 1.5621 ± 1.53618 | 8.0833 ± 7.76232 | 4.8696 ± 1.63910 |
Yellow and black (n = 24) | 44.6971 ± 61.58409 | 0.2246 ± 0.15959 | 2.4242 ± 3.69194 | 10.7917 ± 14.50031 | 5.5913 ± 1.37096 |
Blue and white (n = 24) | 33.0075 ± 42.15658 | 0.2063 ± 0.14467 | 2.3504 ± 3.21087 | 11.1667 ± 13.51864 | 5.1004 ± 1.79847 |
Sig. | 0.865 | 0.87 | 0.249 | 0.397 | 0.095 |
Color_of_Safety_Sign | Mean_SC_Increase_Rate (Mean ± SD) | Mean_HR_Increase_Rate (Mean ± SD) |
---|---|---|
Green and black (n = 24) | 0.8496 ± 0.60927 | 0.1367 ± 0.13586 |
Red and white (n = 24) | 0.5796 ± 0.88858 | 0.1167 ± 0.11461 |
Yellow and black (n = 24) | 0.8813 ± 0.96647 | 0.0738 ± 0.11912 |
Blue and white (n = 24) | 0.8133 ± 1.10886 | 0.0963 ± 0.17126 |
Sig. | 0.654 | 0.428 |
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Chen, N.; Zhao, M.; Gao, K.; Zhao, J. The Physiological Experimental Study on the Effect of Different Color of Safety Signs on a Virtual Subway Fire Escape—An Exploratory Case Study of Zijing Mountain Subway Station. Int. J. Environ. Res. Public Health 2020, 17, 5903. https://doi.org/10.3390/ijerph17165903
Chen N, Zhao M, Gao K, Zhao J. The Physiological Experimental Study on the Effect of Different Color of Safety Signs on a Virtual Subway Fire Escape—An Exploratory Case Study of Zijing Mountain Subway Station. International Journal of Environmental Research and Public Health. 2020; 17(16):5903. https://doi.org/10.3390/ijerph17165903
Chicago/Turabian StyleChen, Na, Ming Zhao, Kun Gao, and Jun Zhao. 2020. "The Physiological Experimental Study on the Effect of Different Color of Safety Signs on a Virtual Subway Fire Escape—An Exploratory Case Study of Zijing Mountain Subway Station" International Journal of Environmental Research and Public Health 17, no. 16: 5903. https://doi.org/10.3390/ijerph17165903