Annual Report on High Pressure Gas
Related Accidents(2015 version)

The High Pressure Gas Safety Institute of Japan (KHK)1.

Introduction

This Annual Report analyzes and evaluates accidents relating to the High Pressure Gas Safety Act that occurredfrom January to December 2015, with an aim of contributing toward future high pressure gas safety measures.
Note that among high pressure gas-related accidents; this Annual Report excludes those involving general
consumers, which pertains to the Act on the Securing of Safety and the Optimization of Transaction of Liquefied
Petroleum Gas.

2.

Accidents relating to the High Pressure Gas Safety Act

The number of accidents relating to the High Pressure Gas Safety Act per year remained around 100 until 1999.
Subsequently, it has increased since 2000 and has remained at a high level in recent years. However, fewer
accidents occurred in 2015 than in the previous year.
One of the causes of the increase in number of accidents in recent years is the increase in number of theft andloss of containers (hereinafter, “theft and loss accidents”). However, it is difficult to discuss theft and loss
accidents by statistically treating them along with explosion, leakage, and other ordinary disasters (hereinafter,“disaster accidents”), because of characteristic differences. Thus, this Annual Report summarizes and analyzes
the high pressure gas-related accidents by separating the theft and loss accidents from the disaster accidents.
Also, the accident countermeasures manuals were revised in 2011, resulting in significant changes in thedefinitions of accidents and items of accident causes. Thus, the analysis and evaluation on accident causes andothers below were conducted separately for the years up to 2010 and those after 2011.
2.1

Changes in number of accidents and analysis/evaluation(1) Changes in number of accidents by year
Figure 1 shows the number of the High Pressure Gas related accidents that occurred in the latest decade (2006to 2015).
In the last five years, the number of accidents occurring in 2011 was 1084, and thereafter 957 in 2012, 836 in
2013, 787 in 2014, and 729 in 2015. The number of accidents in 2015 was the lowest of these years.
Here, the increase in the number of accidents in 2011 was mainly due to the report of 94 accidents that causedby the Great East Japan Earthquake.
Also to note is that the number of theft and loss accidents was 300 in 2015 and this number was fewer than thatof 406 in 2014.

Figure 1

Changes in number of the High Pressure Gas related accidents

Copyright © The High Pressure Gas Safety Institute of Japan 1

(2) Numbers of accidents by category
From this section onwards, the focal point of discussion is placed on disaster accidents.
Figure 2 shows the results of statistic treatment of the disaster accidents that occurred in the last two decades(1996 to 2015), according to accident categories. A notable feature is that the number of accidents has been on
the increase since 2000 even though it had been around 100 accidents every year until 1999.
The breakdown of the 429 disaster accidents that occurred in 2015 shows, in decreasing order, 305 disasteraccidents occurring at production works (71%), 80 during consumption (19%), 24 during transportation (6%),
and 20 others (5%).
As can be seen, the majority of disaster accidents had taken place at production works, and the ratios ofaccidents in 2015 were fairly similar compared to those during the last five years. Thus, it is clear that accident
occurrences at production works have remained at a high level.

Figure 2

Changes in number of disaster accidents by accident category

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(3) Analysis and evaluation based on accident causes
Mentioned above, the definitions of accidents and items of accident causes were changed in 2011. Then Table 1and Figure 3 shows the results of the disaster accidents statistics by causes which occurred during the five years
between 2011 and 2015.
Looking at the 429 disaster accidents in 2015, 203 (47%) were caused by inadequate facility maintenance andmanagement, 87 (20%) were caused by inadequate facility design and fabrication defects, and 46 (11%) werecaused by human factors, together accounting for 78% of the total.
It is important to take countermeasures against inadequate facility design and fabrication defects, andinadequate facility maintenance and management, as well as human error prevention measures such as educationand training.
Table 1 Analysis and evaluation based on accident causes in disaster accidents (2011 to 2015)30

13282621203

261940646

41763084429

72

19112926

17174

0

15621

33

639

61639061381

2013

38

142375

77

28

1823

33

19198

0

15

11650

454

3

18

280

49392

2012

35

111056

65

65

828

31

11

208

0

13

11469

1382

1114

43068

428

2011

22

171150

67

66

8

38

28

19226

0

8

1945

44986

763

0 156

490

Total

202

65

87 354 366 208

87 1009257

1069 237

33 270 110

72 236

Total

Total

Total

Inadequate operational standardsInadequate design

Figure 3

58 146 144

Grand total

Others

8586

Theft

Traffic accident

87

19

Natural disaster

Total

2414

Inappropriate actions

Inadequate container management

953

Faulty operation and judgment

Inadequate seal management

54

2014

Year

Inadequate organizational operation

Inadequate transfer management

2015

Fabrication defects

Inadequate inspection

OthersInadequate inspection management

Human factors

Inadequate corrosion control

Inadequate information conveyence

Organizational
defects

Total

Inadequate facility maintenance andmanagement

Inadequate construction management

Inadequate facility
design andfabrication defects

0 418 2120

Analysis and evaluation based on accident causes in disaster accidents (2011 to 2015)

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2.2

Analysis based on phenomenal categories, human damages, and accident classifications(1) Analysis based on phenomenal categories
Figure 4 shows the statistical results of the disaster accidents that occurred during the last two decades (1996 to2015), classified by phenomenon categories.
The number of disaster accidents in 2015 was 429, and looking at accident phenomena, spout/leakage
accounted for 390 accidents (91%), burst/rupture for 17 accidents (4%), explosion for 7 accidents (2%) and firefor 7 accidents (2%), in that order. The majority of these accidents were spout/leakage.
During the last five years, spout/leakage accounted for 1,860 accidents (88%), burst/rupture for 128 accidents(6%), fire for 78 accidents (4%), and explosion for 27 accidents (1%), in that order.

Figure 4

Change in number of disaster accidents by phenomenon category

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(2) Analysis based on human damages
Figure 5 shows the statistical results of the disaster accidents that occurred during the last two decades (1996 to2015), classified by human damages.
The number of accidents resulting in injury or death was 48 in 2015, accounting for 11% of the 429 disasteraccidents. The number of persons suffering injury or death was 68, making the number of casualties per physicalinjury accident 1.42.
The results of the same calculation for the 2,120 disaster accidents, 190 physical injury accidents, and 348
casualties in the last five years indicate a ratio of physical injury accident of 9% and a number of casualties perphysical injury accident of 1.83.
The number of physical injury accidents was 48 in 2015, which was larger than the 30 that occurred in 2014.
On the other hand, the number of casualties decreased to 68 in 2015, from 74 in 2014.
The greatest number of casualties per accident in 2015 was 7 persons, who were injured by the accident
involving the generation of carbon monoxide during LP gas consumption in a food plant.

Figure 5

Change in number of physical injury accidents and casualties in disaster accidents

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(3) Analysis based on accident classifications
Figure 6 shows the statistical results of disaster accidents that occurred during the last two decades (1996 to2015), classified by accident classifications.
No Class A accident occurred in 2015.
Fewer than 10 Class B accidents took place each year until 2005, which increased to 25 in 2006. More than 50
Class B accidents occurred after in 2008, but reduced to 38 in 2015.
The 38 Class B accidents in 2015 consist of 5 cases of Class B1 accidents, and 33 cases of B2 accident.

Figure 6Changes in number of disaster accidents by accident classification
Table 2

Definition of classification by degree of loss
Contents of loss

Class A(1) Deaths

5 or more(2) Deaths plus serious injuries

10 or more

(3) Casualties (death plus injury)

30 or more

(4) Direct property damage

500 million yen or more

(5) Any accident affecting the public, or which could have developed into a large scale disasterClass B Class B1 (1) Deaths

1 to 4(2) Serious injuries

2 to 9(3) Casualties (injury)

6 to 29(4) Direct property damage

100 to 500 million yen(5) Any accident affecting the public, or which could have developed into a large scale disasterClass B2
Class CAccidents repeatedly occurring at the same works during one year
( excluding Class A and Class B1 accidents )Other than Classes A and B

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＜Contact for inquiries related to this document＞

The High Pressure Gas Safety Institute of Japan (KHK)
Information & International Affairs Department
International Affairs Division
4-3-13 Toranomon, Minato-ku, Tokyo 105-8447
TEL: +81-3-3436-2201 FAX: +81-3-3438-4163
Web: http://www.khk.or.jp/english/index.html
MAIL: oversea@khk.or.jp
Copyright© The High Pressure Gas Safety Institute of Japan