THE TECHNICAL RECORD
ASK THE EXPERTS
Don’t take our word for it.
Over twenty-five years, the AXS material has been examined by testing institutes, universities, a national army, an air force, a defence ministry’s certification contractor, a federal regulator’s advisory committee and a standards body.
Here is what they found, in their own words, with the documents.
Each reference follows the same format: Who they are · What they examined. · What they found. · Results and Conclusions,
01
National Fire Protection Association — NFPA
NFPA 69, Standard on Explosion Prevention Systems — Chapter 14
Who they are
The body whose codes and standards fire marshals, insurers and authorities having jurisdiction in the United States and much of the world apply to flammable-liquid storage.
What they examined.
Whether expanded metal mesh placed inside an enclosure is a recognised method of explosion prevention, and what a mesh must be and do to qualify.
What they found.
The 2024 edition — the current edition of the standard — carries Chapter 14 as first adopted in 2008 and unchanged in substance since. It permits expanded metal mesh for explosion suppression in unoccupied enclosures containing flammable gas or vapour, and names the enclosures:
Results and Conclusions,
Document: NFPA 69 — official NFPA page
02
DO Systems Ltd / Banbury Aviation — UK Ministry of Defence Project
A Summary of Explosive Suppressant for Aircraft — UK MoD Project “eXess” · Report MOD018-001
Who they are
At the time of the report, DO Systems Ltd was a contractor to the United Kingdom Ministry of Defence for special aviation projects. Banbury Aviation carried out aircraft design and certification activities, with testing conducted at RAF Boscombe Down.
What they examined.
A retro-fittable fuel-tank inerting system, including installation, certification, weight, fuel volume, fuel flow and compatibility with the Beechcraft King Air B200 fuel system.
What they found.
The assessment found the eXess mesh an excellent retrofit candidate for explosion prevention and reported that, depending on tank type, minimal or no tank modifications could be required.
Results and Conclusions,
“Depending on the aircraft fuel tank type the retrofit may need minimal or no modifications to the tanks.”
“Approximately 3.9 % more tank volume is available from eXess when compared with foam.”
Document: DO Systems Ltd Report MOD018-001 — AXS Technical Library
03
U.S. Army TARDEC — Fuels and Lubricants Research Facility / Southwest Research Institute
Army Evaluation of JP-8 and Diesel Fuel Exposed to Anti-Detonation Material Filler for Fuel Tank Effects · TFLRF No. 378
Who they are
The U.S. Army TARDEC Fuels and Lubricants Research Facility, operated by Southwest Research Institute in San Antonio under contract to TARDEC in Warren, Michigan.
What they examined.
A Congressionally funded program examining the effect of six fuel-tank filler materials on JP-8 and high-sulphur diesel and the effect of the fuels on those materials. The AXS/eXess material was tested as ADMF Material B.
What they found.
The testing found no adverse effects on the listed fuel properties and no extraction of required fuel additives. The overall evaluation found no particular problems that would preclude use of the materials in the fuel systems examined.
Results and Conclusions,
“Results of extensive testing indicated that additive extraction would not occur.”
Document: U.S. Army TARDEC / SwRI, TFLRF No. 378 — Approved for public release
04
European Commission — Fifth Framework Programme, Project AEROSAFE
Increase of Flight Safety by Development of a New Security System for Fuel Tanks · CRAF-1999-71534
Who they are
An EU-funded research consortium coordinated by eXess, with participating industrial and research organizations including U.L.B.I. GmbH, Lutz Absaug-Technik GmbH, FH Bielefeld, FireEx Consultant and the Vehicle Safety Institute of Graz University of Technology.
What they examined.
Thirty months of material and structural testing including material selection, production, sloshing and abrasion, pressure loss, fuel filling, in-flight testing, filter differential pressure, electrostatic behaviour, explosion testing, mechanical safety and hydrocarbon emissions.
What they found.
Aluminium was identified as the best material of the materials evaluated. The work found very low tank-volume displacement, major sloshing-force reduction, reduced hydrocarbon emissions, explosion protection in the scenarios examined and no requirement for power, sensors or other operating equipment.
Results and Conclusions,
“reduced the fuel sloshing and sloshes forces up the 80 %”
“reduced VOC HC emission and safe environment”
“assure explosion protection in case of projectile punching the tank, fire on board or crash landing”
“require no energy, no sensors and other equipment”
Document: AEROSAFE Final Technical Report
05
United States Air Force — Aero Propulsion Laboratory
Evaluation of Explosafe Explosion Suppression System for Aircraft Fuel Tank Protection · AFWAL-TR-80-2043
Who they are
The United States Air Force research program that carried out a multi-year evaluation of expanded aluminum mesh for aircraft fuel-tank protection.
What they examined.
Approximately three years of combustion-overpressure, ballistic, fuel-compatibility and environmental testing in aircraft fuel-tank configurations.
What they found.
The Air Force work reported strong explosion-suppression performance, ballistic protection and compatibility with the fuel-system and environmental conditions examined.
Results and Conclusions,
“merits serious consideration for application wherever such hazards exist.”
Document: DTIC ADA093125
06
GexCon
Explosion Simulation and Experimental Comparison
Who they are
Norwegian explosion-safety research company based in Bergen and known internationally for explosion modelling and the FLACS explosion-analysis system.
What they examined.
Explosion simulations in a 1.2 m³ vessel using propane-air, compared with measured explosion experiments at different percentages of expanded-aluminum fill.
What they found.
Peak explosion pressure fell from approximately 8 bar in the unfilled vessel to approximately 0.5 bar at full fill in the reported test and simulation results. The computational results closely followed the measured experimental results.
Results and Conclusions,
“Simulation serves as good indication for the behaviour of the gas mixture under different circumstances and allows reasonable prediction of pressure, pressure rise and temperature.”
Document: GexCon AXS Explosion Simulation — PowerPoint presentation
07
TÜV Austria
Explosion Test Reports — 1997 and 1999 · Revalidation — 2015
Who they are
Austria’s accredited testing, inspection and certification organization. The explosion tests were performed by its Electrical Engineering division under European standards for explosion-protected equipment.
What they examined.
1997: acetylene-air testing with and without the expanded-aluminum network. 1999: a 400-litre propane-air vessel test with and without the material. 2015: review of whether the earlier test results remained acceptable under then-current standards.
What they found.
With the material installed, the explosion behavior changed dramatically and the increase in internal pressure was substantially reduced. The 2015 correspondence stated that the earlier results remained acceptable provided material and structure were unchanged.
Results and Conclusions,
“In the scope of the examinations underlying the expertise it could be proved that eXess® explosion protection network possesses reducing efficacy on the occurrence of explosions of gas-air and petrol-air mixtures.”
“The analysis of the eXess® material shows that in the eXess®-area no explosion took place.”
Document: TÜV Austria reports and letters — AXS Technical Library
08
Fauske & Associates — H. K. Fauske and R. E. Henry
Expanded-Metal Networks: A Safety Net to Thwart Gas Explosions · Chemical Engineering Progress
Who they are
H. K. Fauske and R. E. Henry are internationally recognised specialists in process, explosion and nuclear safety.
What they examined.
The physics of expanded-aluminum explosion suppression, including heat absorption, thermal response, flame-quenching length and the relationship between protected volume and deflagration pressure.
What they found.
The expanded-metal network acts as a rapid heat sink and flame-quenching medium, with measured data showing substantial reduction in deflagration pressure as the amount of network increased.
Results and Conclusions,
“inclusion of these means in the next edition of the NFPA 69 standard.”
Document: Fauske & Henry — Chemical Engineering Progress, December 2001
09
United States Senate — Senator Charles E. Schumer
Aluminum Mesh Fuel Tank Liner Program · 15 March 2002
Who they are
The senior United States Senator from New York at the time, writing to the Commanding General of the U.S. Army Tank-Automotive and Armaments Command.
What they examined.
The execution and proposed use of Congressional funding for the Aluminum Mesh Fuel Tank Liner program, including research, development, testing and potential procurement.
What they found.
The letter records continued Congressional support for the Army program and for further testing and deployment of aluminum-mesh fuel-tank liner technology.
Results and Conclusions,
Document: Senator Charles E. Schumer letter — 15 March 2002
10
FireEx Consultant Ltd. — Dipl.-Ing. Richard Siwek
Expertise 50802 — Effect of eXess® Explosion Protection Network in Containers
Who they are
A Swiss fire and explosion protection consultancy led by Dipl.-Ing. Richard Siwek.
What they examined.
Whether containers fully filled with grounded eXess rolls or cylinders could develop electrostatic ignition sources under the conditions described in the Expertise.
What they found.
The Expertise concluded that the specified grounded eXess configuration did not develop electrostatic discharges and therefore did not create electrostatic ignition sources under the standards and conditions cited.
Results and Conclusions,
Document: FireEx Expertise 50802 — AXS Technical Library
11
Federal Aviation Administration — Aviation Rulemaking Advisory Committee
Fuel Tank Foam and Expanded Metal Products Task Group · Final Report — 17 July 1998
Who they are
The FAA’s formal aviation rulemaking advisory body, convened following TWA Flight 800 to examine methods for reducing fuel-tank explosion hazards in transport aircraft.
What they examined.
The feasibility, effectiveness, safety, cost and operational impact of installing reticulated foam or expanded-metal products in transport-aircraft fuel tanks.
What they found.
The Task Group found that expanded-metal products could provide effective fuel-tank explosion protection and noted that aluminum mesh had lower fuel displacement and fuel retention than foam.
Results and Conclusions,
“The aluminum mesh material has a higher weight but lower fuel displacement and retention than foam.”
Document: FAA ARAC Task Group 4 Final Report
12
U.S. Department of Homeland Security — Commercialization Office
Pilot Operational Requirements Document: Blast Mitigation of Fuel Tank Explosions · February 2009
Who they are
The U.S. Department of Homeland Security office responsible for defining operational capability requirements for technologies intended for use by the Department and by state, local and tribal agencies.
What they examined.
The capability gap associated with protecting fuel containers against accidental and deliberate explosion hazards, from vehicle, boat and train fuel tanks to fuel-storage tanks at airports, seaports and service stations.
What they found.
The Operational Requirements Document identified continuous protection without dependence on human intervention, adaptability across numerous fuels, and little or no continuing operation after installation.
Results and Conclusions,
“A solution must work, or be tailorable to work, for all types of conventional and non-conventional fuels to be stored, including but not limited to gasoline, diesel, jet fuel, ethanol, biodiesel, etc.”
“After the initial installation, there is no further operation or maintenance of the solution/product needed.”
Document: DHS Pilot Operational Requirements Document — February 2009
THE RECORD SPEAKS FOR ITSELF.
For more than twenty-five years, expanded-aluminum fuel-tank protection technology associated with AXS/eXess has been subjected to laboratory testing, government research, military evaluation, aviation study, computational modelling, engineering analysis and standards development.
These documents are presented according to their original scope and wording. They include tests, standards, research programs, engineering evaluations, operational requirements and government program records. They are not presented as certification of every individual AXS installation.
