Leading the way in ATEX safety certification

What is ATEX?

ATEX is a recent EU safety legislation based on requirements of the European Directive 94/9/EC for equipment as well as compliance with 99/92/EC for workers. The acronym stands for 'ATmosphère EXplosive' from the original French legislation draft. It sets a framework for controlling potentially explosive atmospheres and establishes guidelines for equipment and procedures to be used in those conditions.

Since July 1 2006, EU operations found to be working without ATEX certification could face fines up to €100,000. If hazardous incidents occur, operations could also face production stoppages and legal prosecution.

There are specific responsibilities placed both on pipeline operators and their service providers. For instance, operation of our ATEX-certified inspection tools anywhere in the world must follow the guidelines or certification will be immediately invalidated for EU operation.

What this means for pipeline inspection

ATEX establishes three explosion-risk zones based on the likelihood of an explosive atmosphere occurring during normal operations. The in-line inspection of oil and gas pipelines falls within the medium-risk zone since an explosive atmosphere can be present during tool launch or receive operations when the pipeline's product, associated vapours or dusts combine with the open air.

1. Safety Strategy:
GE's strategy is to eliminate the presence of ignition sources within the specified zone (within a 3-m radius of the trap door or 1.5 m if the trap is nitrogen purged) by increasing safety precautions for tool electronics and in-field procedures. In-Line Inspection tools contain a number of batteries and sources of static to cause potential risk of explosion: -
  • Potential spark sources on the outside of the ILI tool are removed by ensuring the external electrical connections are either electrically dead during launch/receive or are intrinsically safe.
  • Build-up of potentially explosive atmosphere inside the ILI tool pressure vessel can result through product leakage. Internal electronics contain many potential ignition sources.
  • Electrostatic build-up on the outside of the tool can be caused from wheel bearings, drive cup sliding friction and product relative velocity friction
  • The on-board power source utilises lithium sulfuryl chloride battery cell packs. These have a high energy density to maximize inspection range but can (under electrical load and external pressure) cause fault condition chemical reactions that generate high temperature, high pressure and electrolyte leakage inside the ILI tool vessel. Any safety system has to ensure that battery fault conditions do not destroy the electrical safety circuits inside the battery vessel; otherwise the tool can arrive at the receive trap in an electrically live or thermally hot condition.
  • Lithium cell pack faults can generate high volumes of SO2, which results in high internal pressure. At the receive trap this results in high internal overpressure when the trap is vented. There is danger of ILI tool vessel doors blowing off sometime during the receive operation.
  • ILI tools can remove large amounts of miscellaneous sludge and debris from pipelines that can emit vapours even after traps have been purged with Nitrogen.

2. Design and manufacturing
The first step toward ATEX certification for GE's PII Pipeline Solutions business was a comprehensive quality assurance initiative at our major tool development sites in Germany, Canada and the UK. ATEX Quality certificates (extensions of ISO 9001) were awarded in June 2005, December 2005 and March 2006 respectively - well ahead of deadline. Each site then began an aggressive program of upgrades to our magnetic, caliper and ultrasonic inspection tools.

3. Tool modifications
Compare ATEX legislation to house construction, it lays out parameters for the final structure - but not necessarily for the specific hardware and materials that go into building it.

Take for example the regulations pertaining to battery packs. The typical unit has half a dozen critical components from an ATEX perspective, but there were no established design standards to use as reference. This uncertainty was compounded by the many inspection technologies GE has to offer. So our engineers had to develop individual solutions for each of our technologies.

We reviewed existing standards for electronic components used in various industries and operating conditions, adapted best-case solutions to our specific needs and designed new approaches where existing ones could not address the distinct characteristics of an in-line inspection. Each incremental development was submitted for ATEX approval before proceeding.

4. Personnel and procedures
The final area for ATEX certification involved our in-field personnel and processes. In addition to the guidelines and quality assurance program put in place, all our field crews have ATEX specific training and individual certification. There is also a set schedule for ongoing evaluation and training.

To date, 197 GE personnel have been directly involved in our ATEX certification program. Without it, diminished inspection resources would put the integrity of our customers' pipelines at risk, legally and operationally.

Atex Certification

Customer launch and receive traps are typically assessed as zone 2 or zone 1 potentially explosive environments. Accordingly our inspection tools are designed for zone 1 operation - classified as Group 2B equipment (for non-mining applications) according to 94/9/EC.

Our ATEX safety case is designed to address the risks outlined above. Use of the Intrinsically safe standard EN60079-11 predominates but the safety case cannot be generated solely around this standard. Accordingly a number of strategies outside the ATEX EN60079 standards are used that require independent notified body approval and certification - even for operation in zone 2 environments.

ATEX Certificate

For more information, please contact:

Germany: Wolfgang Markus - wolfgang.markus@ge.com
Canada: Michael Campbell - michael1.campbell@ge.com
UK: Derek Smith - Derek.Smith@og.ge.com