Annual Report on Liquefied Petroleum Gas(LPG) Related Accidents(2017 version)

The High Pressure Gas Safety Institute of Japan (KHK)1. Introduction
This Annual Report describes accidents that occurred in 2017 related to facilities for supplies andconsumptions of Liquified Petroleum Gas (hereinafter, “LPG”) at home or on business, which areregulated by the Act on the Securing of Safety and the Optimization of Transaction of Liquefied Petroleum
Gas (hereinafter, the “LPG Act”). This report also describes analyses of the data of the accidents in 2017by comparing with the past.
2. Definitions
2.1 Definition of accidents(1) LPG accidents[1] Leakage
A case in which LPG leaked, but it did not catch fire and cause human damages ofpoisoning and asphyxiation. However, leakage of a very little amount of LPG
from joints as little as soap bubbles formed when those of threaded parts or rubber
tubes are soaked by soap water is excluded.
[2] Leakage andCases in which LPG leaked, and it resulted in an explosion or a fire caused by theexplosion
explosion, as follows.
A. Leakage and explosion, when the explosion resulted from leaked gas only.
B. Leakage, explosion and fire, when a fire broke out following explosion causedby leaked gas.
[3] Leakage andA case in which a fire resulted from leakage of LPG excluding those covered byfire[2] above. This is not limited to that recognized as a fire by the fire department.
Here, a fire without leakage, which is caused by the overheating or the failure of
LPG appliances including their accessories or by spreading of flames from acooking oven, grill, etc., is not classified as a LPG accident.
[4] Poisoning andA case in which human damages of CO poisoning and asphyxiation are caused
asphyxiation
due to incomplete combustion, leakage of LPG, or leakage of exhaust gas fromexhaust pipes, etc., at LPG consumption facilities.
(2) Other accidents (not classified as LPG accidents)[1] Accidents caused by suicide, damage by intention, mischief, theft, or other similar causes[2] Accidents resulting from a natural disaster
Example) Accidents caused by facilities’ damages resulting from collapse of houses due toearthquake
Example) Accidents caused by facilities’ damages resulting from flood and landslide
Even if accidents are resulted from natural disasters, however, those caused by defects in toppling
prevention measures, fallen snow prevention measures (snow shelters, protective boards), or otherinsufficiencies in safety measures, are classified as LPG accidents.
[3] Accidents involving portable cooking stoves and gas cartridges[4] Other accidents not categorized in the LPG accidents of (1) above
2.2 Classification of human damages
Classified as follows according to the level of damage.
Death:
When a person was confirmed to have died within five days from the time ofaccident
Seriously injured: When a person suffered an injury at the time of accident that took 30 days ormore for full recovery
Slightly injured:
When a person suffered an injury at the time of accident that took less than 30days for full recovery

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3. LPG accidents
3.1 Occurrences of accidents in the past

It is noted a characteristic of accidents data in Japan that thenumber of leakage of gas, which has not caught a fire and caused
no casualties due to poisoning or asphyxiation, is counted as a
LPG accident.

Figure 1: Accident occurrences and casualties by year
Table 1: Change in the number of accidents and casualties by year
Year
Number of accidents
Rate to the previous year
Number of deaths
Number of injuries

1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992
112 170 217 217 299 368 540 497 581 638 570 793 761 714 570 559 545 496 515 401 390 306 262 194 146▲3352280382347 ▲81710 ▲1128 ▲4 ▲6 ▲20 ▲2 ▲3 ▲94 ▲22 ▲3 ▲22 ▲14 ▲26 ▲2538694433525974406556726360504351363542293736271331146 236 283 301 398 389 679 543 523 684 640 825 758 723 650 645 529 550 477 381 336 327 233 171 162

Year
Number of accidents
Rate to the previous year
Number of deaths
Number of injuries

1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
1128288 101
687579788790 120 105 105 219 239 234 185 204 227 260 210 187 179 139 185▲23 ▲27715 ▲33105 ▲112333 ▲130 109
9 ▲2 ▲21101115 ▲19 ▲11 ▲4 ▲2233
73121469582472104445113120013583
80 109648266736964
868858789879 148
8388
85
5276
605250

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Figure 1 shows the number of accidents that occurred between 1968 and 2017 and the resulting casualties.
Looking at the data, the number of accidents increased gradually during the 1960s and the 1970s along withthe number of households using LPG and reached a peak in 1979 with 793 accidents, causing 63 casualties.
This was the year that marked the highest number of accidents and casualties. In July 1978, a part of the LPG
Act was revised : measures such as dealer's obligation to general consumers, the establishment of a certified
research institution system, etc. were implemented.
In August 1980, a large-scale city gas explosion took place that resulted in enormous human damages marked
by 15 deaths and 222 seriously and slightly injured persons. In February 1981, Ministerial Ordinance Reform
was carried out : safety standards of the basement were established, installation of gas leak alarm equipmentfor LP gas for the basement and business facilities was obliged, and odor of LP gas concentration
strengthened.
Thereafter, the number of accidents continued declining linearly from the late 1980s, falling below 100 in
1994, to 82. Meanwhile, amendments to Act and Ministerial Ordinances were implemented several times. For
example, in July 1985, the Ministerial Ordinance Amendment was implemented to strengthen the installationof end gas faucets (fuse gas stoppers) with excess overflow safety mechanisms and the connection method ofrubber tubes for eating house.
After that, initiatives for eradicating accidents, such as promoting the deployment of safety devices inconjunction with the public and private sectors, have been promoted.
3.2 Accident situations by phenomenon
Table 2 shows the number of accidents by phenomenon that occurred between 2007 and 2017. Looking atthat of 2017, the number of leakage-only accidents that did not start fire or explosion was more than half oftotal accidents. Compared to the previous year, the number of leakage-only accidents increased by 22, leakage
and explosion (fire) accidents increased by 14.
Table 2. Number of accidents by phenomenon
2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017
Leakage
Leakage andexplosion(Fire)
Leakage and fire(Excluding explosion)
CO poisoning andasphyxiation
Total

113

115

84

76

116

160

113

98

99

84

106

64

53

45

60

55

48

48

59

43

27

41

51

60

4260

45

44

43

27

31

19

35

11

6

14

8

118

6

3

6

9

3

239

234

185

204

227

260

210

187

179

139

185

4. Analysis of accident situations
The following kinds of LPG accidents that have occurred frequently were analyzed.
(1) CO poisoning accidents (excluding asphyxiation)
As shown Figure 2, three CO poisoning accidents occurred in 2017, showing an decreased by six fromthe previous year. Among three, two accidents happened in the industrial facility where industrial
ventilation alarming and CO alarming were not installed.
[1]
Incomplete combustion of a dishwasher. (one case)[2]
Supply and exhaust failure without the operation of Ventilation fan in using rice cooker.
(one case)

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Figure 2: Number of CO poisoning accidents by year and casualties(2) Buried pipes accidents
The pipes that are installed between LPG cylinders and a gas meter are called supply pipes, and are
installed between a gas meter and consumption devices like heaters are called distribution pipes in Japan.
Pipes are installed on the ground or underground. The number of supply pipe accidents is greater thandistribution pipe accidents.
Figure 3 shows that 41 accidents involving buried pipes took place in 2017, a increase of eight from theprevious year.
Causes of accidents include damages in 29 accidents (supply pipes in 23 accidents and distribution pipes
in six accidents) and deterioration due to corrosion in 12 accidents (supply pipes in four accidents anddistribution pipes in eight accidents). In many cases, damage is caused by a construction company
erroneously cutting or breaking in a construction unrelated to gas facilities, causing gas leakage. In sucha case, since people are involved directly and treatment such as gas stoppage is taken relatively quickly,
most of them have not reached a large-scale accident.

Figure 3. Number of buried pipes accidents by year and casualties

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(3) Bulk supply accidents
In 2017, two accidents involving bulk supply (supply facilities only) occurred, showing a decrease of
three from the previous year. The breakdown of these accidents is shown below.
*Bulk supply refers to supply of liquefied petroleum gas into bulk storage tanks from portable LPG
generators (bulk tank trucks). See Figure 4.
[1] Deterioration of a sealing property of a resin plug. (one case)[2] A minute gap of a flange joint. (one case)

Figure 4. Bulk supply system
Protector
Pressure Relief Device
Regulator

Liquid Inlet ValveGas Outlet Valve
Liquid outlet valve

Level Gauge

Filling Port

Figure 5: Bulk Storage Tank

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5. Number of accidents that resulted in death or injured
Number of the accident that described so far contains non death and non injured cases. Of course, most of theleakage only accident didn’t result in death or injured. Table 3 and Figure 6 show the number of accidents that
resulted in deth or injured by phernomenon.
Table 3. Number of accidents that resulted in death or injured by phenomenon
Number of accidents

Leakage

Number of deaths
Number of injuries

Leakage andexplosion (Fire)
Leakage and fire
(ExcludingExplosion)
CO poisoning
and asphyxiation

Number of accidents
Nnumber of deaths
Number of injuries
Number of accidents
Number of deaths
Number of injuries
Number of accidents
Number of deaths
Number of injuries
Number of accidents

Total

Number of deaths
Number of injuries

200820092010

201120122013

2014

20152016

2017

50
7361451512062862
480

00025
139170241438556
4148

1013814917117831664
58300032039
110151113454
188

10227033
10013813746
18500024030
1501763545
352

10138050
902131451
176

10122137
808611437
260

1011602110190
292705210124029
1201530540050

Figure 6: Number of accidents by phenomenon that resulted in death or injured

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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
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