Idris Jeelani, Alex Albert, Kevin Han. Hazard Recognition â A visual Search Perspective. 60,000fatal injuries are experienced in construction industry world wide ...
Hazard Recognition – A visual Search Perspective Idris Jeelani, Alex Albert, Kevin Han North Carolina State University Introduction
Results
60,000 fatal injuries are experienced in construction industry world wide. 1 every 9 minutes!
R1
Recognizing hazards is the 1st step in safety management Adequate Safety Control
Physical Barrier Recognized
About 50% of hazards remain unrecognized!!
Procedural Barrier Inadequate Safety Control
Not Recognized
Why hazards remain unrecognized? Examine
Visual Search
Hazard Recognition
Hazard Recognition is a visual search Process
Scanpath: person A:
13 Reasons why hazards remain unrecognized
Hazards recognized: 31%
1. 2. 3. 4.
Selective attention Premature termination of search. Visually unperceivable Unassociated with primary task.
5. 6. 7. 8. 9. 10. 11. 12. 13.
Hazards perceived to impose risk. Low prevalence hazards. Unknown potential hazard set. Multiple hazards from single source Hazzard without immediate effect Task unfamiliarity. Operational unfamiliarity. Source detection failure. Latent hazards
R3
R2: What are the parameters of an
unrecognized?
efficient hazard Search?
Exploratory Study with workers
13 factors that lead to unrecognized hazards
Training
𝒄
Hazard Recognition
Training
2500
Eye Tracking overlay on 3D point cloud
2233 2145
Over 90 % accuracy achieved in computing fixations
2000
1453
1500
1355 1125 1028
1017 1000
930
500
𝒃
𝒄′
Longer Search Duration More Number of Fixations Wider Attentional Distribution Longer Fixation Duration
Hazards recognized: 73%
Visual search 𝒂
Scanpath: person B:
Method R1: Why do hazards remain
R2 Characteristics of efficient visual search
Hazard Recognition
0 1
2
𝒄 = 𝒄′ + 𝒂𝒃
3 Manual
4
System
Indirect Effect Validation study
Direct Effect Total Effect
Practical contribution Intervention improved performance by 43%
R3: How to automate eye tracking data analysis?
100%
90%
80%
Personalized hazard recognition Visual cues for systematic hazard recognition performance feedback Personalized Intervention to improve HR
% Hazards Recognized
Exploratory study with Experts
70%
60%
43% Improvement
50%
40%
30%
Before Training
20%
After Training
10%
Personalized eye-tracking Metacognitive prompts to encourage self-diagnosis and correction visual attention feedback
