Gas supply incidents

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.

Gas Report 2013-14 Fig 15
Gas Report 2013-14 Fig 15, by ggodsman

Figure 15

Gas supply incidents – Workplace and non-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 Report 2013-14 Fig 16
Gas Report 2013-14 Fig 16, by ggodsman

Figure 16

Gas supply incidents – Workers and 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

Gas Report 2013-14 Fig 17
Gas Report 2013-14 Fig 17, by ggodsman

Figure 17

Gas supply incidents – Type of gas

Gas Report 2013-14 Fig 17a
Gas Report 2013-14 Fig 17a, by ggodsman

Figure 17A

Gas supply incidents – Percentage of consumers by 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%.

Gas Report 2013-14 Fig 18
Gas Report 2013-14 Fig 18, by ggodsman

Figure 18

Gas supply incidents – Type of incidents resulting from NG

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%.

Gas Report 2013-14 Fig 19
Gas Report 2013-14 Fig 19, by ggodsman

Figure 19

Gas supply incidents – Type of incidents resulting from LPG

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.

Gas Report 2013-14 Fig 20
Gas Report 2013-14 Fig 20, by ggodsman

Figure 20

Gas supply incidents – Equipment type

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.

Gas Report 2013-14 Fig 21
Gas Report 2013-14 Fig 21, by ggodsman

Figure 21

Gas supply incidents – Incidents resulting in fatality, injury or hospitalisation

Gas Report 2013-14 Fig 21a
Gas Report 2013-14 Fig 21a, by ggodsman

Figure 21A

Gas supply incidents – Incidents resulting in property damage