CAUSES AND MEASURES OF FALL ACCIDENTS ON RESTORATIONWORK AFTER THE GREAT EAST JAPAN EARTHQUAKE
Hiroki Takahashi1, Tomohito Hori1 and Yasuo Toyosawa1
1

National Institute of Occupational Safety and Health,
1-4-6 Umezono, Kiyose, Tokyo 204-0024, Japan

Many buildings and structures in the Tohoku region along the Pacific coast weredestroyed by the Great East Japan Earthquake. It is feared that fall accidents willcontinue to occur during the restoration work related to this disaster because such
falls have been the most prevalent form of recent work-related accidents. In thisstudy, we analyse the fall accidents that have already occurred during therestoration work for the Great East Japan Earthquake with the purpose of
preventing future fall accidents. A study of the number and causes of theseaccidents was conducted. Fall accidents have occurred most frequently from a roof
or ladder. The main causes of the accidents are as follows: The operations chief
was not present at the construction site and safety belts were not used on the roof.
To make these findings accessible to the restoration workers, we have compiled theresults into a simple illustrated booklet.

Introduction
The Tohoku Earthquake occurred off the Pacific coast of Japan at 14:46 on March 11, 2011,
followed by tsunamis and aftershocks. Many buildings and structures in the Tohoku region weredevastated by the earthquake, tsunamis, and aftershocks, which together are referred to as theGreat East Japan Earthquake.
During the demolition of a building damaged by an earthquake, there is a high risk that thebuilding will collapse. Moreover, demolition and separate work are undertaken simultaneously at
the same site, therefore increasing the likelihood of work-related accidents. It is feared that fall
accidents will continue to occur during the restoration work related to the Great East Japan
Earthquake because such incidents have been the most prevalent form of recent work-relatedaccidents.
In this study, we analyse the fall accidents that have already occurred during the restoration workwith a view to preventing future fall accidents. A study of the number and causes of these
accidents was conducted. The data used in this study were taken from four days or more during theperiod of March 11, 2012 to September 11, 2013.
For practical use of these results, we have developed illustrations for each accident type andrecommendation.

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Outline of all work accidents
To date, the work accidents of four days or more due to the restoration work after the Great East
Japan Earthquake have involved 642 people (including 36 fatalities) from March 11, 2012 toSeptember 11, 2013. The occurrence of number of accidents according to the number of months
after the earthquake is shown in Figure 1. The most work accidents occurred within the first monthafter the earthquake, affecting 111 people (including 6 fatalities). The work accidents follow adecreasing trend with the lengthening of time after the earthquake. The number of work accidents
after 17 to 18 months was 12 (including 0 fatalities).
The state of the occurrence of accidents by pattern is shown in Figure 2. Falls were the mostcommon type of accident, affecting 271 people (42.2% of all work accidents). The “get between”
group of accidents affected 72 people (11.2%), the “come flying” group of accidents affected 69people (10.7%), and the “fall down” group of accidents affected 45 people (7.0%). These fourtypes of accidents account for 71.1% of all work accidents. Falls mainly occurred during roof work.

Occurrence of number of accidents(people)120
Absences

100

Fatalities

80
60
40
20
0

0-1

1-2

2-3

3-4

4-5

5-6

6-7

7-8

8-9 9-10 10-1111-1212-1313-1414-1515-1616-1717-18

Passage of months (months)

Figure 1. Relationship between occurrence of number of accidents and passage of months

Collapse
3.9%Crash4.2%

Other
8.1%

Fall
42.2%

Take crash
6.2%
Cut
6.4%
Fall down
7.0%
Come flying
10.7%

Get between
11.2%

Figure 2. The state of the occurrence of accidents by pattern- 130 -Outline of fall accidents
The state of the occurrence of the fall accidents that were biggest accident was analysed. An
outline of fall accidents is shown in Figure 3.

FallͲrelatedaccidents(271people)
Roof,beam,purlin,andgirder(77people)

Reroofingandrepairs
(23people)

Otherrepairs(23people)

Puttingupsheetrock(10people)

Ladderandsoon(61people)

Scaffolds(39people)

Theworkerhadhisfootontheinsulatingmaterialandheslippedandfell.

Theworkerslippedwhileputtingupsheetrockandhefell.

Demolitionandgoingup
anddown(21people)

Theworkerslippedonsnowwhileroofdemolition.

Goingupanddown
andsoon(27people)

Whentheworkerwascomingdownaladderfromtheroof,theladderslipped.
Helosthisbalanceandhefellwiththeladder.

Fromstepladder(34people)

Whentheworkerwasrepairingawallusingastepladder,heslippedandfell.

Falsestep,slip(22people)

Whentheworkerwasrepairingaroof,hefalsesteppedfromthefloorofthescaffoldsandfell.

Erectingand
disassembling(8people)

Truck(23people)

Theworkermissedhisfootingontheroofwhilereroofingandhefell.

Whentheworkerwasholdingpartofthescaffoldswhileitwasbeing
disassembled,helosthisbalanceandfell.

Unsafebehavior(9people)

Whenatransferplatformwasmovedwhileaworkerwasstandingonit,he
losthisbalanceandfellfromtheplatform.

Fromplatform(14people)

Whentheworkerwasguidingconstructionmachineryfromtheplatformofthetrucktostowsandbags,helosthisbalanceandfell.

Fromthedriver’sseatorplatform(9people)

Whentheworkersteppeddownfromtheplatformofthetruckwhile
disposingofrubble,heslippedandfell.

Falsestep,slip,thrown
offbalance(11people)

Whentheworkerclimbedupashelfduringrepairworkinawarehouse,his
handslippedandhefell.

Other(9people)

Theworkerfellduringdemolitionworkofahousebecausetheflooronthe
secondstorycavedin.

Openings(8people)

Fromopeningsofasecondfloor(8people)

Whentheworkerputhisfootontheplywoodlaidacrosstheopeningtotheroof,theplywoodbrokeandhefell.

Other(43people)

Collapseofwalls
andsoon(23people)

Thewallcollapsed,andtheworkerfelldownwhilerepairingahouse.

Fromconstruction
machinery(20people)

Theworkerslippedandfellduringdownfromthedriver’sseatofa
constructionmachine.

Building,structure(20people)

Figure 3. Outline of fall accidents- 131 -

Occurrence by causal agentsThe state of the occurrence by causal agents in falls is shown in Figure 4. Figure 4(a) is accidents
that led to an absence from work, and Figure 4(b) is the fatal accidents.
In the occurrence by causal agents of absence accidents, the “roof, beam, purlin, and girder” groupaffected 69 people (27.1%), the “ladder and so on” group affected 61 people (23.9%), the“scaffolds” group affected 37 people (14.5%), the “truck” group affected 23 people (9%), and the“building, structure” group affected 18 people (7.1%). Those five types of accidents comprise
81.6% of all falls.
The “roof, beam, purlin, and girder” group led to the most fatalities (8 people, 50% of fallfatalities). The “openings” group led to 2 fatalities (12.5%), the “building, structure” group led to 2fatalities (12.5%), and the “scaffolds” group led to 2 fatalities (12.5%). Those four types of falls
comprise 87.5% of all fall-related fatalities. The “ladder and so on” group did not cause any
fatalities.

Other
18.4%
Building,
structure
7.1%

Other
12.5%

Roof, beam,
purlin, andgirder
27.1%

Scaffolds
12.5%
Building,
structure
12.5%

Truck
9.0%
Scaffolds
14.5%

Roof, beam,
purlin, andgirder
50.0%

Ladder andso on
23.9%

Openings
12.5%(a) Absence accidents(b) Fatal accidents
Figure 4. The state of the occurrence by causal agents in falls

Occurrence of sick and wounded
The state of the occurrence of sick and wounded due to falls is shown in Figure 5. “Fractures”
were the most common type of fall injury, affecting 201 people (74.2% of all fall-relatedinjuries). Bruising affected 50 people (18.5%), and “sprains and so on” affected 12 people(4.4%). Those three types of injuries account for 97% of all fall-related injuries.

Sprainand so on
4.4%

Wound
1.8%

Other
1.1%

Bruise18.5%

Fracture
74.2%

Figure 5. The state of the occurrence of sick and wounded due to falls- 132 -

Conclusion
Occurrence and causes
In this study, we have analysed the falls related to the restoration work after the Great East Japan
Earthquake with a view to preventing future falls. Falls were the most common type of work
accident, affecting 271 people (42.2% of all work accidents).
In the fatal accidents caused by falls, the most common cause was falling from a roof and being hit
on the head. In relation to absences from the workplace, the “roof” and “ladder and so on” groups
were the most common due to the injuries they caused to the feet, chest, back, etc. The mostcommon causes for these injuries were no operation chief on site, not using a safety belt on theroof, the ladder being set up inappropriately, and the lack of an assistant.

Measure of accidents
Based on our results, the measures of falls during the restoration work after the Great East Japan
Earthquake as follows:
1. You should thoroughly investigate the extent of damage to the building before beginning work.
You should make a work project from those results.
2. You should have conscious of a safety work to each worker.
3. There should be an operations chief for each structure and type of building.
4. When the strength of a building is insufficient, you should review methods for increasingstability.
5. When you work over 2 meters from the ground, you should use work roof such as scaffolding.
When you erect the scaffolding, you should devise measures to prevent falls, such as theinstallation of a net or using a safety belt. The scaffolds use actually a preceding method.
6. When you work in a high place, you should use good flexion and nonslip shoes.
7. The low-rise house is instability because a beam and so on is damaged. Therefore, you should
not much work at high place work.
8. Ladders should be adequately wide and strong, with nonslip steps and a tip-over safety device.
The ladder should be supported by an assistant.
9. For openings, you should use an enclosure, a guardrail, or a cover.

Practical use of the results
For practical use of these results, we have developed illustrations for each accident type andrecommendation (e.g., Takahashi, H., Hori, T., and Toyosawa, Y, 2013). An example of theseillustrations is shown in Picture 1.

Acknowledgment
This work was supported by Construction Industry Workers' Compensation Friendly Society.
The picture was drawn by cartoonist Shinnosuke Tsuchida. We are gratefully acknowledged here.

References
Takahashi, H., Hori, T., and Toyosawa, Y. (2013). Causes and measures of work accidents on
restoration work of the Great East Japan Earthquake [in Japanese]. Tokyo: National Institute ofOccupational Safety and Health, and Construction Industry Workers’ Compensation FriendlySociety.

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(2)

(4)

(5)

(3)

(6)

(1)Thisaccidentoccurredontheroofafterarainfall.
(2)Abluesheetwascoveringadamagedroof,butapartofthesheetwastornfreebytherain andthewind.
(3)Theworkerbegantorepairthesheetontheroof.
(4)Theroofwaswetandslippery.
(5)Theworkerslippedandfell.
(6)Theworkerfellfromtheroofandhithisheadanddied.

Picture 1. The worker fell when he was repairing the blue sheet on the roof

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