DEVELOPMENT OF AR BASED SAFETY EDUCATIONSUPPORT SYSTEM IN CONSTRUCTION SITE
Michiyuki Hirokane1, Sho Banba1 and Katsutoshi Ohdo2
1

Faculty of Informatics, Kansai University, 2-1-1 Ryozenji, Takatsuki,
Osaka 569-1095, Japan
2
National Institute of Occupational Safety and Health, 1-4-6 Umezono, Kiyose,Tokyo 204-0024, Japan

In this research, we developed the experience-based safety education support systemthat can assess the risk easily in the construction site. This system can putinformation tag about some dangerous spots where the labour accident such as
falling and colliding are easy to be happened in the real construction sites throughthe tablet typed PC or the smart phone. The accumulated information as thedangerous spots can display in the construction site through the tablet typed PC or
the smart phone. When an information tag indicated on the display is touched, themore detail information about the dangerous spot is displayed and we can do therisk assessment just on site. And also, it is able to share the risk information with all
workers in the construction site through the smart phone. Moreover, various risk
information accumulated by using this system can be confirmed on the map of theconstruction site, and these information can be also shared and utilized for the safety
education in the construction site.

Introduction
Among all the industries, it is said that most fatal accidents occur in the construction industry. In
the past, countermeasures were implemented with the main focus on facilities (Uta et al., 2011).
In order to utilize time and space effectively, more safety education for workers is being
conducted in a classroom. However, it is also true that, from the perspective of construction
companies, safety education should be conducted not only in a classroom but also in a way toimprove workers' awareness of danger more effectively (Okami, 2010). Taking into
consideration the various work schedules and costs, conducting enough safety education on site
regularly is not easy (Hirokane et al., 2008). Without taking work schedules and costs into
consideration, it was reported that the most effective safety education methods on site were safety
training, discussion of accident cases, and collecting and sharing the workers' near-miss stories(Hirokane et al., 2010). Some companies conduct experience-type safety education to increaseawareness of danger by letting the workers experience simulations (Okami, 2010). Experiencetype safety education means to conduct practical training in front of the workers for instancessuch as when steel stock on a construction site falls or a worker falls from a high elevation.
Although this type of training is the most effective to increase awareness of danger, there is aproblem with the amount of time required for preparation of space and equipment. Therefore,
safety education which does not require much time and space but effectively increases on site
awareness of danger in a short time is preferable.

- 139 -In this study, we tried to construct a system to enable easy and experience-type safety
education on site. Concretely, using Augmented Reality (AR) technology on a smart phone ortablet-type device, we registered the accident prone areas. Via the smart phone or a tablet-typedevice, the registered information was shown as a tag on the screen with the actual construction
site as the background. Previously registered information was confirmed by tapping the tag on
the screen. Using this system, we constructed a portable shared system utilizing a smart phone ora tablet-type device.

Outline of AR based safety education support system
This system registers detailed information of dangerous locations together with the mapped
location information taken from a GPS. Utilizing technology to display the results after more
information is added to the registered information using computer and AR technology, disaster
information and information on dangerous locations can be displayed. As the medium, having
taken into consideration the cost, operability and functionality to use the AR technology, thesystem was constructed so that it could work on a tablet-type device, such as a smart phone. A
portion of the registered information is shown in Table 1. This table is actually used for on-siterisk assessment, and the following items can be registered: Date of Inspection, Name of Inspector,
Type of construction/Job name, Risk/Hazard, Possible accident, Estimation, Assessed Rate(probability and severity), Assessment (level and degree of risk), Risk reduction/Removal
method, Measurement for possible accident, Preparation plan, Implementation process, etc. The
information can be reviewed on the screen as detailed.
Table 1. Input items for risk assessment
Date of inspection
Name of inspector
Type of construction / Job name
Assessed rate
Probability
Severity
Assessment
Level
Degree of risk
Risk reduction / Removal method
Plan of measurement action
Situation of measurement action
Evaluation of measurement action

Input method of risk assessment information

In order to register information, we registered accident prone locations on a smart phone which
was loaded with the system constructed in this study. By entering information on each location,
the mapped location information from the GPS was referenced, and the risk information perlocation was recorded. You can register various danger spots, and the registered information canbe shared using tags, greatly simplifying the gathering of information.

Confirmation method of risk assessment information

As detailed information, the information including Date of inspection, Name of inspector andType of construction/Job name is registered (Table 1). Each category can be checked by tapping
the tag. The flow to register detailed information is shown in Figure 1. For Figure 1, Date ofinspection, Name of inspector, Type of construction/Job name to be Assessed, Estimation,Assessed rate (probability and severity), Assessment (level and degree of risk), Implementation
process and Evaluation of implementation are entered first, and then the accidents thought to be arisk or hazard are entered per item. Because the risk or hazard information is the information
added after the accident occurs, the information on Risk reduction/Removal and Implementation
process are entered after the selection. As for Possible accident, it is the information on which- 140 -

type of accident is likely to occur and the information regarding it, such as Measurement forPossible accident and Method of implementation, which should also be registered.
Date of Inspection
Name of Inspector
Type of construction / Job name that is assessed
Estimation
Assessment
Risk / Hazard

Possible accident

Measurement for reducing
the risk / hazard

Measurement for avoiding
the possible accident

Prevention plan

Method of implementation
Implementation process

Evaluation of implementation

Figure 1. Input items and flow of input process

Design of Tags

In this study, additional information is displayed on a projection screen using the camera functionof a smart phone with the image of the actual construction as its background. We made theadditional information easy to understand intuitively and visually using tags. By not displaying
detailed information until the user taps the appropriate tag, we prevented additional informationand the image of the construction site from being highlighted on the screen. Figure 2 shows anexample of the tag display. Figure 2 shows an area where a fall can occur, and the area is easily
checked while walking around the construction site. The tag becomes larger as the user nears thedangerous area so that the user can intuitively understand where the dangerous area is. In order
to inform the user which type of accident can occur depending on the risk type, the tags ofdifferent designs are used.For example, if the risk is slipping or falling, the top two tags ofFigure 3 are used. If the ceiling is low or there is a danger of electric shock, the bottom two tagsof Figure 3 are used. We had the tags designed to represent the most prevalent accidents, but thetype of risk can be added later.

Figure 2. Example of tag displayed on the screen- 141 -Slippery surface

Caution!

Watch your head

Electric shock risk

Figure 3. Design example of some tags

Input screen on a smart phone

On the registration screen, the user registers the information as shown in Table 1, such as Date ofinspection, Name of inspector, Type of construction/Job name, Risk/Hazard, Possible accident,Estimation, Assessed rate (probability and severity), Assessment (level and degree of risk), Risk
reduction / Removal method, Measurement for Possible accident, Preparation plan,Implementation process, etc. By letting the user select the items, we aimed to simplify theregistration and reduce entry errors. Figure 4 shows an example of the registration screen on asmart phone. The Date of Inspection can be adjusted using the "㸩" and "㸫" keys. The Nameof inspector column can be entered freely, and when various situations can be expected such ascountermeasures and the implementation process, this method was utilized. As for Type ofconstruction, we adapted the selection method. Figure 4 shows the screen to select the type ofconstruction after tapping the "Type ofconstruction" box. For Job Title, Risk / Hazard andPossible accident, the selection method is used. Stars are used to show the level of risk visually.
Figure 4 shows the risk level of 3.5. The risk level can be selected from 5 different levels bytapping the screen.

Date of inspection
Ground improvement work
Retaining wall foundation
work

Name of inspector

Connecting road work

TanabeBuilding removal work

Type of construction

Temporary work

Temporary work

Other

Level of risk

Figure 4. A part of input screen on a smart phone- 142 -

Display on the interactive map

In this study, we constructed a system using AR technology to place a tag on the image of theactual construction site taken with the camera function of a tablet-type device. We also added afunction to place a tag to display the registered information of the dangerous areas on the aerial
photograph of the Google Map utilizing the GPS information obtained at the time of registration.
Figure 5 shows an example of a tag being displayed on the aerial photograph based on thelocation information recorded at the time of registration. By tapping the tag, the user can see
detailed registered information as described in the previous section. Using this function, we
made it possible to use it in the pre-education program for workers and show them the dangerous
areas of the construction site before they commenced work.

Figure 5. An example of a tag display on the interactive map

Conclusion
Today, safety education which does not take up much time and space and still can improve thesafety awareness of construction workers effectively in a short time is required on construction
sites. In this study, we tried to construct a system to share safety management information
utilizing AR technology. We believe that our system can provide experience-type safety
education quickly and easily as a part of classroom education, experience-type safety educationand safety training. Unlike existing experience-type safety education, the safety education using
our information sharing system does not require preparation such as equipment. All you have to
do is to ask the workers to hold a smart phone, loaded with our system, and walk around theconstruction site and go through safety training exercises, such as identifying dangerous areas.
Other workers can check the tags by placing their smart phone cameras toward the dangerous
areas previously registered using our system. The tags contain safety information and accident
information. When workers get close to the dangerous areas where the tag is displayed and tap
the tag, they can display the detailed information registered about the area on the screen. By
reading and seeing the registered information regarding the dangerous areas and accident areas
and learning from that experience, workers can visualize the dangerous areas easily. If workers
repeat this operation, they can apply their knowledge to additional areas similar to the dangerous
areas registered. They can improve their safety awareness and recall safety information.
Participating workers can also provide feedback to the registrant on dangerous areas which are
yet to be registered and may find dangerous areas that the registrant did not consider dangerous.
By asking the workers to provide feedback, you can provide an opportunity for them to stayaware of dangerous areas of their own accord. In addition, utilizing the display function with the- 143 -interactive map, we made it possible to use it in the pre-education program for workers and show
them the dangerous areas of the construction site before commencing work. Furthermore, theregistered information can still be utilized after the particular work has finished and can be usedas training material for safety education at an additional construction site.
In the future, we would like to add mode display functions using the interactive map andestablish a connection between the registered information and past accident cases. Not only that,
we would like to utilize the information as part of on-site safety education whereby theevaluation of the utility of our system and modification need to be implemented. Lastly, thisstudy was supported in part by MEXT.KAKENHI (23510213).

References
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Hirokane, M., Shiraki, W. & Ohdo, K. (2010). Hazard prediction activities for safety education.
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