This report is an analysis of gas incidents reported to EnergySafety over a ten year period from 1 July 2004 to 30 June 2014.

The distribution of gas across Western Australia is varied in terms of reticulated natural gas (NG), liquefied petroleum gas (LPG) and bottled LPG.

There were 817 gas related incidents reported in the ten years from 2004/05 to 2013/14. Of these, 74% were related to gas utilisation and 26% to gas supply. Overall gas supply incidents recorded by EnergySafety have shown a higher safety outcome as compared to gas utilisation.

Analysis of workplace and non-workplace incidents indicates that gas supply had more workplace incidents in comparison to gas utilisation where a higher number of incidents occurred in a non- workplace setting.

There were four fatal incidents which resulted in six fatalities over the reporting period. The nature of gas incidents can result in multiple fatalities as was the case in 2006/07 when an incident involving a camping stove being used indoors resulted in the death of 3 people.

There was a fatality in 2013/14 in which the victim was alleged to have been using LPG during the manufacture of an illegal substance. A fire and explosion resulted causing the victim to sustain burns and later succumbed to his injuries.

There were 16 incidents which resulted in serious injury in 2013/14 bringing the total number of incidents in this category to 73 since 2004/05.

There were 107 incidents which resulted in minor injury during the reporting period. 13 such incidents occurred in 2013/14.

The Gas Standards (Gasfitting and Consumer Gas Installations) Regulations 1999 require that an incident involving the sudden discharge of gas or that otherwise relates to gas and causes or is likely to cause injury to a person or damage to property must immediately be reported to the Director of Energy Safety and to the relevant gas supplier where applicable. The Gas Standards (Gas Supply and System Safety) Regulations 2000 specify levels of major discharge of gas in incidents that need to be reported to the Director of Energy Safety.

All reported incidents are recorded on a database maintained by EnergySafety. The information contained within this report has been compiled from this data. This report provides a comparative analysis of trends in terms of frequency of incidents. EnergySafety is the regulator for downstream gas incidents in Western Australia.

The introduction of mandatory reporting of gas incidents in 1999 resulted in a significant increase in the amount of data recorded, indicating a greater awareness of the reporting requirements. This report focuses on the ten year period from 2004/05 to 2013/14.

Gas related incidents can vary from a gas leak to a fatality. This report analyses incidents resulting in fatality, serious injury and minor injury and has been categorised into two major sections based on utilisation and supply of gas. The majority of incidents reported relate to gas utilisation and this segregation allows for a better understanding of the data in identifying trends.

EnergySafety acknowledges the contribution of the Economic Regulation Authority for its permission to utilise and reprint the ‘Gas Licensing Distribution Systems and Trading Locations’ map as sourced from its website.

FAFR – Fatal Accident Frequency Rate 

LPG – Liquid Petroleum Gas

NG – Natural gas

PMP – per million population 

WA – Western Australia

Gas related incident

For the purpose of this report a gas related incident refers to any incident that involves the sudden uncontrolled discharge of gas or that otherwise relates to gas and may or may not cause or be likely to cause injury to a person or damage to property.

FAFR

Fatal accident frequency rate is calculated with the formula:

FAFR =  Number of fatal accidents per year                                         
              Number of people at risk to the exposure of gas (population)

For ease of communication, the FAFR is multiplied by a million. Therefore the figure arrived at is the FAFR x 10⁶. This figure allows a comparison of gas safety performance.

This is also referred to in the report as ‘the fatalities per million population’.

Fatality

An incident in which gas was found to be the cause and that resulted in accidental death.

Serious injury

An incident in which gas was found to be the cause and that resulted in such an injury that hospitalisation was required.

Minor injury

An incident in which gas was found to be the cause and resulted in such an injury that may have required medical attention but did not require hospitalisation.

Other incidents

A gas related incident that has not resulted in injury or fatality.

Major discharge

A major discharge is the unplanned and uncontrolled release inside a building of 10 m³ or more of gas or the unplanned and uncontrolled release in the open air of 1,000 m³ or more of gas.

Limitations of this report

• This report is based on information derived from rigid legacy systems due for replacement in the near future. Parts of the data have been manually noted and then summarised for analysis. While care has been taken in the process of documenting this report, the risk of human error is still present.
• Fatalities where gas was involved but was not found to be the cause of the incident have been excluded from this report.
• The number of incidents in this report may vary in comparison to other documents previously released by EnergySafety. Although legislation requires prompt notification of incidents, there can be extended delays between when an incident occurs and when notification is received and this can impact on the data. This is more evident in cases with low severity. In other instances, some incidents may be found to be non-gas related after investigation and hence not included in the report.

To arrive at the FAFR, the demographic population has been utilised as the number of people at risk to the exposure of gas.

Distribution of gas across the state is varied. The Perth Metropolitan Area, Kalgoorlie, Esperance, Bunbury and Geraldton are serviced by reticulated natural gas. Margaret River, Leinster, Albany and Hopetown have reticulated LPG, while bottled LPG is available and utilised throughout WA.

1 Sourced and reprinted with permission from the Economic Regulation Authority.

There were 817 gas related incidents reported from 2004/05 to 2013/14. The number of reported incidents per million population has been represented in Figure 2 below. The most number of incidents were reported in 2004/05 and although there has been a variation in the numbers reported the overall trend has been declining at a steady rate indicating a positive outlook for gas safety.

Approximately 76% of the incidents occurred in a metropolitan area, which may also be indicative of the concentration of population utilising gas.

In 2013/14 there were 32 gas incidents per million people. Seven incidents per million people resulted in a form of injury. A large number of incidents did not result in any injury.
 
All the incidents recorded can be broadly classified into gas utilisation and supply incidents. 74% of all incidents in the reported period were related to gas utilisation. The high number of reported gas utilisation incidents may be due to the legislative requirement to report gas incidents.

For supply incidents, there is a requirement to report incidents which have a major discharge of gas. Figure 3 below provides information on the number of incidents reported to EnergySafety each year.

 

Within the 2004/05 to 2013/14 period there have been four fatal incidents that resulted in six fatalities.

A fatal incident which occurred in 2006/07 caused the death of a mother and her two children. It resulted from an escape of LPG from a two burner camping gas stove believed to have been left unattended for a brief time. Nearby combustibles caught fire which ultimately consumed the front portion of the house in Karrinyup. The three deceased were found in a bedroom unable to escape the fire.

A fatality which occurred in 2009/10 related to an explosion involving a gas cylinder where cylinder abuse was identified as the cause. The fatality was a result of medical complications relating to burns received from the explosion.

There was a fatality which occurred in 2012/13 due to LPG leaking from a mechanical bolted sleeved coupling on a gas main in the verge, near the residence at 282 Middleton Road, Centennial Park, Albany and permeated into the lower ground floor bedroom of the residence. The presence of LPG as a vapour cloud in the bedroom was ignited by an electrical source. The explosion and fire that followed proved fatal to a resident.

The fatality reported in 2013/14 involved a victim that was alleged to have been using LPG during the manufacture of an illegal substance. There was a fire and explosion in which the victim sustained burns and later succumbed to his injuries.

Figure 4 shows that fatalities arising from gas incidents may impact more than one person in a single incident as is evident from the incident which occurred in 2006/07 involving a camping stove causing three fatalities.

For ease of comparison, the ‘Fatal Accident Frequency Rate’ is utilised to compare gas safety performance in a changing demographic population. This is also referred to as the fatalities per million population.

Table 1 below lists the FAFR over the reporting period and Figure 5 provides a graphical view of the number of fatalities per million population. On average one fatal gas incident has occurred every three years.

Table 1: Fatal Accident Frequency Rate

Year	FAFR x 10^6
2004/05	0.00
2005/06	0.00
2006/07	1.42
2007/08	0.00
2008/09	0.00
2009/10	0.44
2010/11	0.00
2011/12	0.00
2012/13	0.40
2013/14	0.39

 

Since the establishment of EnergySafety in 1994 there has been no gas related fatalities involving a gas worker which suggests that the safety of gas workers is generally maintained at a high level.

Non-fatal gas incidents have been classified into two groups, those causing serious injury requiring hospitalisation and those causing minor injury. Figure 6 below shows the number of incidents resulting in serious injury per million population. Trends indicate an increase in incidents reported in this area.

The majority of incidents resulting in serious injury involved cookers, recreational equipment (predominately barbeques) and water heaters.

Unsafe installation was identified as a major cause of incidents involving cookers and component failure/design fault in recreational equipment. Incidents involving water heaters resulted mainly from improper use of the unit.

Minor injuries resulting from gas incidents show a decreasing trend over the reporting period with a slight increase in the number of incidents in the last two years as indicated in Figure 7.

40% of incidents resulting in minor injury were caused by operational defects related to component failure. A further 30% of incidents were caused by improper use or unskilled interference with gas equipment.

There were 607 gas utilisation incidents reported during the period 2004/05 to 2013/14. 30% occurred within a workplace setting and the remainder within the larger community. Figure 8 below shows the distribution between workplace and non-workplace incidents over the past ten years.

Figure 8A shows the percentage distribution of workplace and non-workplace incidents.

Figure 9 below is a classification of incidents according to broad categories of workers and the general public. Gas workers were involved in 9% of the incidents.

Gas utilisation incidents – by type of gas

Natural gas, LPG (Propane), LPG (Butane) and auto gas are the main types of gas utilised in Western Australia.

Figure 10 below provides a graphical view of incidents in relation to the type of gas. 52% of incidents involved NG, followed by LPG (Propane) at 46%.

The percentage of incidents involving butane and auto gas is low compared to NG and LPG (propane). There have been 6 incidents involving butane and 7 incidents related to auto gas over the ten year period.
 
Figure 11 and figure 12 are a classification of the type of incidents reported to EnergySafety segregated by the type of gas. This breakdown of incident types has not altered by a significant margin over the ten year reporting period. Charts have not been prepared for butane and autogas due to the low number of incidents in those categories.

An analysis of incidents by equipment type has revealed that there is a wide range of apparatus involved in gas utilisation incidents as shown in Figure 13 below.

The most common types of equipment found in utilisation incidents are water heaters (hot water systems) accounting for 26% of the incidents. This was followed by LPG (storage) cylinders at 14% and recreational equipment (which includes gas barbeques) at 13%.

Gas cookers (including stoves and hot plates) are also an area of interest at 11%.

A study of the incidents involving water heaters revealed that most of the incidents occurred while lighting the pilot light. 38% of incidents involving water heaters resulted from component failure and 28% from lack of maintenance.

Component failure was also found to be the cause in 41% of LPG storage incidents and in 62% of incidents involving recreational equipment like barbeques.
 
Figure 14 is an analysis of all gas utilisation incidents from 2004/05 to 2013/14 and indicates that 0.5% have resulted in fatalities, 11.4% in serious injury requiring hospitalisation, 15.7% resulting in minor injuries and 72.5% did not result in any injury.

The same data set has been analysed in terms of damage to property, with an almost even split between incidents resulting in some kind of property damage and those with no impact to property.

 

There were 210 gas supply incidents recorded during the reporting period from 2004/05 to 2013/14. In contrast to gas utilisation incidents, the majority of gas supply incidents occurred within the workplace. Figure 15 displays the number of workplace and non-workplace incidents, with workplace incidents amounting to 82% of all recorded supply incidents. This has increased compared to the previous report analysing the ten years 2003/04 to 2012/13 where 79% occurred in the workplace.

Figure 16 illustrates that supply workers were involved in just 3% of the incidents and gas workers in 5%. Workers from other occupations were found to be involved in 75% of incidents and approximately 14% affected the general public.

 
 
Gas supply incidents – by type of gas

Analysis of the type of gas found in recorded supply incidents reveals 94% of incidents involved NG. In comparison, incidents involving LPG accounted for 6% as displayed in Figure 17 below. However, this figure may be more representative of the size of the distribution system for NG and LPG. Figure 17A depicts the number of incidents per 1,000 customers.

Figure 17: Gas supply incidents – Type of gas

Further analysis of incidents involving NG, as per Figure 18 below indicates that 82% of incidents resulted in a gas leak or release. In contrast to gas utilisation at 57%, just 13% of gas supply incidents involving natural gas resulted in a fire. If explosions and flashovers are considered in the category of a fire (as they do result in a fire) this percentage increases to 15%.

Figure 19 below provides percentages for the different types of incidents but they are minimal in number when compared to natural gas. As the data suggests, the percentage of incidents resulting in a fire (inclusive of flashovers and explosions) is 38%.

Figure 20 below is an analysis of the type of equipment found in gas supply incidents. It was found that the main gas pipe was a factor in 87% of the incidents. Other incidents involved gas service piping (7%) which incorporates the meter box and the piping from the mains to the meter.

Figure 21 below is an indication of the injury types sustained in supply incidents. There were no fatalities recorded in gas supply incidents until 2012/13 when there was one fatality.

Of all gas supply incidents, 1% resulted in hospitalisation and 1% in minor injuries. The large majority of 97% of incidents have resulted in no injury. 9% of incidents resulted in damage to property.

 

The fatal accident frequency rate is declining over the reporting period, but there is an increasing trend in the area of serious injury. Cookers, recreational equipment and hot water systems were found to be most commonly involved in incidents resulting in serious injury. Trends for minor injuries show a decreasing rate over the reporting period.

Analysis of gas utilisation incidents shows that the majority of incidents occur in a non- workplace environment, with natural gas being the primary gas source. The most common types of equipment found in utilisation incidents are water heaters (hot water systems), followed by LPG (storage) cylinders and recreational equipment. Component failure and lack of maintenance were the common causes of most utilisation incidents indicating that more information or education in this area may be necessary to prevent such incidents.

Gas supply incidents show the inverse of utilisation with the majority occurring in a workplace environment. Gas workers accounted for just 5% of these incidents and workers from other occupations accounted for approximately 75% of these incidents. The majority of these incidents are the result of third party strikes or damage to the network by people not residing at the premises nor the owner of the network. Further analysis in this area and the causes of these incidents may help to reduce gas supply incidents in the workplace.

The majority of gas supply incidents were related to natural gas but this is more reflective of the area of distribution piping and the size of the consumer base compared to LPG. Analysis of the number of incidents against consumer numbers indicates that LPG accounts for four times more incidents per thousand consumers when compared to NG.