New Zealand Executive Government News Release Archive

Results of testing and investigative work into reported fuel system failures after the introduction of premium unleaded petrol were released today.

The following overall conclusions were reached by the oil industry (BP, Caltex, Mobil, Shell), the motor industry (Motor Vehicle Manufacturers Association, Associated Motor Importers and Distributors of New Zealand, Motor Trade Association, Association of Automotive Parts and Accessories and Repco) and Government agencies (Ministries of Commerce, Transport and Health, New Zealand Fire Service and the Occupational Safety and Health service of the Department of Labour).

Overall outcome of tests and investigative work

The new premium unleaded petrol can be used with the same confidence as other fuels. Test results confirm that with the new 48 percent limit on total aromatics and the voluntary 40 percent limit on toluene and/or xylene, premium unleaded is not expected to cause rubber fuel system parts to fail prematurely.

However, rubber fuel system components do deteriorate with age. People are therefore reminded that, whatever fuel they use, they need to make sure that the fuel systems of their cars, boats and other petrol driven engines are checked regularly and that only approved and warranted replacement parts are used and that these parts are fitted correctly.

Did the introduction of premium unleaded cause an increase in fuel system failures?

In general it does not appear that the introduction of the new petrol led to a significant increase in fuel system problems:

• the New Zealand Fire Service confirms that fuel system related car fires attended by the Service are no higher than in previous years;
• an independent survey of 96 workshops and garages in Auckland, Rotorua, Tauranga, Wellington and Nelson shows no significant increase in overall fuel system repairs in February-March 1996 compared with the same period in 1995.

However, there are some indications that early supplies of high aromatic (over 50 percent) and high aromatic/high toluene (56/54percent) petrol may have contributed to problems with some rubber fuel system parts:

• testing of fuel hoses and fuel system seals by Industrial Research Limited (IRL) shows that the high aromatic/high toluene petrol causes more swelling than other petrols. Depending on the type of component, international standards allow up to 50 percent swell. This was exceeded for some rubber componentry in the high aromatic/high toluene petrol.
• statistical analysis of incidents reported to oil company helplines suggests that the Bay of Plenty and Northland, which received a high aromatic/high toluene shipment in January, experienced a higher level of fuel system problems than other areas;
• there appears to have been a similar increase in service station pump diaphragm failures in these areas.

On the other hand, the survey of workshops and garages showed a lower level of fuel system repair work in the Bay of Plenty in 1996 compared to 1995.

Is there a problem with fuel system parts?

The IRL tests concluded that new and in-service rubber fuel system parts are not expected to fail prematurely in petrol with an aromatic content of 50 percent, which is above the limit now applying (48 percent or less total aromatics and with up to 40 percent toluene plus xylene).

All fuel hoses tested bar one met the international standard for swelling in both premium unleaded and unleaded 91. Further tests are being done on that hose and the supplier is being contacted by the Ministry of Consumer Affairs.

Independent inspection by a senior mechanic, a rubber expert and others of 140 failed fuel system parts concluded that some 20 percent were probably fuel related, but not necessarily related to premium unleaded. A higher proportion of failures were related to age and poor condition.

Have any public health issues been identified?

OSH and the Ministry of Health have concluded that premium unleaded presents no greater hazard to workers or to the general public than other petrols. Sensible precautions must be taken when handling all fuels. Inhalation and skin contact should be avoided.

The Ministry of Health will continue to monitor the levels of benzene and other aromatic compounds in the ambient air and will recommend changes to fuel specifications or emission controls if required.

Further action

The oil industry has confirmed it will maintain its voluntary 40 percent limit on toluene plus xylene.

The Ministry of Commerce will continue to monitor the level of aromatics in petrol sold at petrol stations and in supplies to bulk storage terminals.

Oil industry helplines will continue to respond to calls from customers experiencing fuel problems. The oil industry fund administered by GAB Robins will continue to handle compensation claims into May. After that the oil industry will deal with any claims on an individual company basis.

Officials have been directed by Cabinet to report on whether standards for rubber components for vehicle fuel systems and petrol pump dispensing equipment are adequate and whether checks of fuel systems in vehicle Warrants of Fitness should be enhanced.

Further Information

A summary of the findings of individual elements of the testing and investigative programme is attached. A detailed report will be published in May.

Contact Numbers:

Oil Industry BP Oil New Zealand Limited Beppie Holm, 04 495 5605 (work); 04 568 3226 (home); 026 05 169 (pager)
Caltex Oil (N.Z.) Limited Denise Beazley, 04 495 6066 (work); 04 237 7920 (home) 025 432 954 (mobile)
Mobil Oil New Zealand Limited Rowan Macrae, 04 498 4248 (work); 04 562 8050 (home); 025 457 034 (mobile)
Shell New Zealand Limited Hugh Massam, 04 498 0149 (work); 04 475 7586 (home)

Government Agencies The New Zealand Fire Service Stu Rooney 04 496 3619 (work)
Ministry of Commerce Mike Lear 04 474 2604 (work)
Ministry of Health Lyn Harrison 04 496 2008 (work)
Ministry of Transport Ross Weenink 04 498 0634 (work)
Occupational Safety and Health, a service of the Department of Labour Lyall Mortimer 04 495 4458 (work)

Motor Industry Association of Automotive Parts and Accessories Inc. Barry Hellberg 04 472 1071
Motor Trade Association of New Zealand Inc. Brian Nelson, Chief Executive, 04 385 8859 (work)
Motor Vehicle Manufacturers Association of New Zealand Inc. Perry Kerr, Chief Executive, 04 473
6700 (work). Glenn Johnston, Chairman Technical Committee, 09 266 3400 ext 8718 (work), 09 534 7841 (home), 025 934 983 (mobile)

PREMIUM UNLEADED PETROL
Summary of Testing and Investigative Work
This summary has been prepared by the oil companies, government agencies and motor industry organisations noted below.

1 Introduction

1.1 Background

Premium unleaded petrol first came on sale at two service stations in Auckland and one in Tauranga in November/December 1995. Initial batches of premium unleaded petrol from NZRC began arriving at the Wiri terminal in Auckland in early January. Widespread distribution of premium unleaded began in the Waikato/Bay of Plenty in mid-January.

The oil industry was first notified on 4 March 1996 that premium unleaded may be causing accelerated deterioration of rubber fuel system parts in relation to a home-built aircraft. This attracted considerable media attention. The oil industry also experienced problems with some types of diaphragms in its own petrol dispensing equipment. Widespread reporting of similar problems arising in vehicles began on 7 March.

1.2 Initial Response

The oil industry took steps to advise the public of the possibility that premium unleaded may be affecting rubber fuel system parts and on precautions the public should take. It also made arrangements to compensate people whose vehicles experienced problems that may have been caused by premium unleaded petrol.

In response to concerns that the higher level of aromatics in premium unleaded (38-56 percent compared to 32-52 percent for super 96) may be accelerating the deterioration of rubber fuel system parts, the oil industry imposed a voluntary limit of 50 percent aromatic content on all premium unleaded manufactured in or imported to New Zealand with effect from 13 March. Motor vehicle manufacturers and new vehicle importers confirmed that a 50 percent aromatics maximum would be realistic as overseas manufacturers have been testing rubber fuel system parts at this level for at least the past 10 years, and in most cases longer.

The Government subsequently specified a limit of 50 percent aromatics at the wholesale level with effect from 21 March 1996, reducing to 48 percent with effect from 18 April 1996. The total aromatics content of premium unleaded petrol sold from all service stations has been below 50 percent since special deliveries were completed on 24 March. Many service stations are now selling premium unleaded with aromatics under 48 percent.

With effect from 1 April the oil industry also imposed an interim voluntary limit on two of the aromatic compounds in premium unleaded - toluene and xylene. From that date all premium unleaded manufactured at the Marsden Point Refinery or imported from overseas has contained less than 40 percent toluene plus xylene by volume.

1.3 Testing and investigation programme.

A comprehensive testing and investigation programme was jointly developed by the oil companies, the motor industry and Government agencies. The implementation of the programme has involved extensive consultation locally and with overseas experts. The results of the investigations are summarised below.

1.4 Aromatics Levels

The Ministry of Commerce testing confirmed that average levels of toluene and total aromatics in premium unleaded petrol in 1996 were higher than the levels in super leaded petrol in 1995 for Auckland, Mt Maunganui, and for New Zealand overall. There were no significant increases in levels of xylene from 1995 to 1996.

2 Number of Fuel System Failures Before and After Premium Unleaded

2.1 Survey of Fuel System Repair Work

An independent research company was contracted to conduct a survey of fuel system repair work completed by a sample of 96 Motor Trade Association members during the last two weeks of February and the first two weeks of March in 1995 and 1996. Workshops surveyed were located in Auckland, Rotorua, Tauranga, Wellington and Nelson. This included areas where premium unleaded had been on sale for short and long periods, areas where the aromatics levels in the petrol had exceeded 50 percent and areas where the aromatics levels had been well under 50 percent.

Results indicated that:

• the total amount of fuel system repair work in 1996 did not increase significantly compared with the same period in 1995;
• there was an increase in the fuel system repair work undertaken in the Auckland area, largely in the week when media coverage of the issue peaked;
• there was no relationship between the number of fuel system repairs, the length of time premium unleaded was available in each market or peak aromatic levels. For example there was no increase in fuel system repair work in workshops surveyed in the Bay of Plenty where premium unleaded had been on sale the longest and the high aromatic (56 percent) petrol with 54 percent toluene was sold.

2.2 Analysis of Fuel System Related Fires

The New Zealand Fire Service reviewed the number of fuel system related fires it attended before and after the introduction of premium unleaded petrol and reported that:

• no evidence to indicate that fires are directly related to the new petrol;
• the numeric trend (based over the last 9 years) has not increased for the first quarter of 1996 beyond previous averages for the same quarter in earlier years; in fact the number of fires in the first quarter of 1996 could be slightly less than previous years.

An independent assessment by Environmental Science & Research Ltd (ESR) of the NZ Fire Service car fire data concluded that:

• there has been no increase in the numbers of car fires attributable to fuel system failure either overall, or in the Bay of Plenty area alone, or in cars over 10 years old. Although Fire Service data for the first three months of 1996 are incomplete with a (4-6 week lag in receipt at national HQ), the number of fuel system related fires as a percentage of total car fires has not increased.

2.3 Survey of Sales of Rubber Fuel System Parts

The Association of Automotive Parts and Accessories has discussed concerns over the use of premium unleaded petrol. Whilst no statistical results were available the Association stated that none of their members have had product that has been adversely affected by premium unleaded petrol.

3 Cause of Fuel System Failures After Premium Unleaded Introduced

3.1 Incidents Reported to Oil Company Helplines

GAB Robins, an independent loss adjustor, was contracted by the oil industry to assess all the premium unleaded related incidents reported to oil company helplines.

3.1.1 Number of Incidents

By 3pm Saturday 20 April 1996, a total of 2463 people reporting incidents had been referred to GAB Robins. The incidents dated back to the beginning of the year.

Of the 1029 incidents which have been diagnosed as fuel system related, where the date is known, 11 occurred before February; 55 in February, 776 in March and 187 up to 20 April.

Reported incidents peaked at 214 on 18 March. Since Easter incidents have averaged 40-50 calls per day, falling to around 20-30 per day during the week ending 19 April.

3.1.2 Nature of Incidents

Contact has been made with 2197 of the 2463. The incidents are made up as follows:

Problems with other petrol driven engines - boats, mowers, . . . .

91 percent of the reported fuel system problems and fires involved vehicles that were manufactured before 1987. Problems reported most frequently were failed fuel hoses followed by failed fuel system seals (O-rings) and fuel pumps.

3.1.3 Assessment of Cause of Vehicle Fuel System Fires

Assessments were conducted by loss adjustors and qualified mechanics. In many cases it was difficult to distinguish whether the petrol or the age or condition of a part caused the fuel system to fail. Lack of maintenance was involved in around one third of the fuel system problems reported. Assessments of the vehicle fires are as follows.

3.1.4 Payment of Claims

An oil industry fund, administered by GAB Robins, was established to compensate people for direct costs incurred where premium unleaded may have contributed to vehicle failure.

By 3pm Saturday 20 April offers to settle had been made to 1720 people. Compensation on a 'without prejudice' basis had been paid to 320 claimants. Payments have averaged around $220 per claim.

3.2 Assessment of Failed Parts

People compensated for fuel system related problems have been asked to return the failed parts for assessment. An independent assessment has been undertaken by an experienced automotive engineer, an elastomer (rubber) expert and others.

Age and condition of the parts were considered to have been the most likely cause of failure. Red staining caused by leaking leaded Super petrol (which was dyed red) was also evident in a few fuel pumps, indicating leakage prior to the introduction of premium unleaded petrol.

By 5pm Friday 19 April 140 returned parts had been examined. Cause of failure was summarised as follows:

Note: This sample is not necessarily representative of all failed parts.

3.3 Analysis of Fuel System Related Incidents Reported to Helplines

The oil industry and the Ministry of Commerce analysed the fuel system related incidents reported to the oil company helplines to determine whether there were correlations between the number of incidents in an area, the length of time premium unleaded had been supplied to that area and the levels of aromatics in the petrol supplied.

This analysis concluded that:

• there appears to be some relationship between the higher aromatic fuels and the number of fuel system related incidents;
• the effect is most noticeable on incidents reported in regions receiving the high toluene fuel rather than with overall aromatic levels. In these regions incident rates seem to be between 1.5 to 3 times higher than elsewhere;
• no evidence was found of a relationship with incidents involving fires.

3.4 Analysis of Petrol Pump Diaphragm Failures

The four oil companies reported that they had experienced problems with some types of rubber diaphragms in petrol pumps in the first quarter of 1996. Information was gathered on the number and type of failures by area during the first quarter of 1995 and 1996 (to end March). This was analysed by the oil industry and the Ministry of Commerce to determine whether incorrect parts had been used; whether there was a significant increase in the number of failures in 1996 and whether this related to the introduction of premium unleaded petrol.

The analysis concluded that:

• there is a range of diaphragms of varying performance installed in pumps;
• these diaphragms fail periodically (around 3-4 percent a year);
• there was a significant increase in the number of diaphragm failures in pumps dispensing 96 octane petrol coinciding with the time and location of the high aromatic/ high toluene shipment of premium unleaded petrol;
• this increase was probably exacerbated by the use of inappropriate diaphragms.

3.5 Industrial Research Limited Test Programme

The oil industry contracted Industrial Research Limited to conduct an elastomer test programme to determine the impact different fuel compositions have on a range of fuel hoses and fuel system seals (O-rings) on sale in New Zealand. The programme was developed together with the Ministry of Commerce, Auckland University and the Motor Vehicle Manufacturers Association.

Tests involved standard test fluids and a number of commercial fuel samples with aromatic levels ranging from 28 to 56 percent, including samples with varying levels of toluene and xylene. Testing was conducted on new and good condition used fuel hoses and polychloroprene (Neoprene), nitrile, and fluoroelastomer (Viton) O-rings. Parts were tested in single fuels as well as a sequence of fuels (leaded Super, followed by premium unleaded and then unleaded 91) to replicate conditions experienced in service.

Standard test methodology was used to measure the extent of swell as a predictor of overall performance of the part. Performance was compared with SAE (Society of Automotive Engineers) and ASTM (American Society of Testing Materials) standards. Some components were also tested for swell at high temperatures and for burst pressure.

The elastomer test programme identified that:

• increasing aromatics content increases swell in fuel system parts. Swelling of Viton and nitrile O-rings was within the appropriate ASTM standards on all commercial fuels tested except the 56 percent aromatics fuel containing 54 percent toluene;
• new and old rubber fuel system parts would not be expected to fail prematurely in fuels with total aromatic content of up to 50, or in 48 percent aromatic fuel containing up to 40 percent toluene, plus xylene;
• the amount of swell depends on the type of elastomer with Viton parts swelling significantly less than nitrile parts which in turn swell less than Neoprene parts;
• of the aromatic compounds tested, toluene causes more swell than xylene and mesitylene respectively;
• swell generally stabilises within 72 hours for nitrile and Neoprene but takes more than 168 hours for Viton;
• elastomers such as Neoprene which are not designed for vehicle fuel systems should not be used;
• with one exception, fuel hoses tested met the swell requirements under the SAE J30 standard for carburetted vehicles in all the fuels tested. The one aftermarket hose that failed to meet the standard in all fuels is being investigated further.

This summary was prepared and issued by the following organisations:

Oil Industry
BP Oil New Zealand Limited
Caltex Oil (N.Z.) Limited
Mobil Oil New Zealand Limited
Shell New Zealand Limited

Government Agencies
The New Zealand Fire Service
Ministry of Commerce
Ministry of Health
Ministry of Transport
Occupational Safety and Health Division, Department of Labour
Motor Industry
Association of Automotive Parts and Accessories Inc.
Motor Trade Association of New Zealand Inc.
Motor Vehicle Manufacturers Association of New Zealand Inc.
Associated Motor Importers and Distributors of New Zealand Inc. 

Home || Ministers || Policies || Speeches || Departments