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Explosive Ordnance Storage

Spantech Explosive Storehouses – Earth Covered Buildings to Store High Explosives

Spantech’s most popular Defence building is the Spantech Explosives Storehouse (ESH), an earth-covered building specifically designed to store explosive ordnance (EO) used by Defence forces.

The Spantech ESH is a 7 Bar Type 4 Igloo (as defined by eDEOP101 the Australian Department of Defence’s explosives storage and handling regulations). The buildings can be licenced to store up to 75,000kgs (NEQ) (165,000lbs) of HD1.1 at minimal (D3 and D4) NATO separation distances. The building also meets applicable NATO and US regulations.

For clarification, Explosive Storehouses (ESH) may also be called:

  • explosive ordnance (EO) storage buildings
  • earth covered buildings (ECB)
  • EO stores
  • igloos, or
  • bunkers

Spantech has three standard ESH designs:

  • Spantech 13m ESH
  • Spantech 23m ESH and
  • Spantech 17.5m ESH

All feature the Spantech 300 Series steel panel lining all internal surfaces of an earth-covered reinforced concrete structure. The numerator in the name describes the nominal internal width of the building.

The 13 and 23m feature an internal arch rising from floor level. The arch is a continuous segment of a circle. These buildings have been widely used by the Australian Department of Defence since 1991.

The Spantech 17.5m ESH features a light-weight arched roof supported by vertical side and end walls. This design was developed in 2017 specifically to meet the needs of the Australian Defence Force as they modernise their EO logistics across the nation.

Each ESH is designed to meet different storage requirements:

  • types of munitions and ordnance
  • number of pallets
  • pallet stacking heights
  • type of mechanical handling equipment to be used and
  • siting requirements of the ESH within the EO depot.

In their standard configuration the Spantech ESH can store:

Nominal Width Standard Length Max. Extended length Standard Pallet Capacity* Maximum HD1.1
Spantech 13m ESH 13 m 13 m 25 m 96 75,000 kgs (NEQ)
Spantech 23m ESH 23 m 15.6 m 25 m 220 75,000 kgs (NEQ)
Spantech 17m ESH 17.5 m 21.21 m 25 m 360 75,000 kgs (NEQ)

* Based on 1200 x 1200 x 1200 pallets stacked up to 3 pallets high within a standard length building in a layout which complies with NATO standards. Bulked-out pallet capacity may exceed the listed pallet capacity in the order of 30%. 

Design Options

All current ESH designs can be constructed in a range of lengths from 13m to 25m long to suit individual requirements.

Spantech has the design experience and qualifications to modify most elements of the design to suit a customer’s individual requirements.  For example, Spantech offers a range of options in the the following key areas:

  • main blast door sizes
  • one or two main blast doors
  • blast door operating systems (manual, mechanical or electric, or a combination of these)
  • the number and location of personnel doors (including within the main blast door)
  • blast valves
  • ventilation systems (passive and/or mechanical ventilation)
  • air conditioning and/or dehumidification systems
  • floor heights, slopes and floor finishes
  • line marking options
  • standard pallet racking or bespoke racking for over-sized ordnance and packaging
  • erosion prevention or control systems
  • lightning arresting and earthing systems
  • roof access and fall prevention systems
  • electrical layout options and
  • security system options.

See recent Explosive Storehouse projects.

Spantech ESH Tested in Full-Scale Explosive Trials

20081203104925_00001Spantech Explosives Storehouses have been subjected to seventy-five thousand kilogram (75,000kgs) (NEQ) HD1.1 blasts at minimal NATO separation distances.

The Australian Department of Defence conducted a comprehensive series of full scale donor and receptor trials in 1991 and 1992 at the Woomera Rocket Range in South Australia.

The Second Test

The Second Test video below is available to Defence personnel and those in a related defence industry. Contact us to receive the password for this video…


The aim of the trials was to determine the ability of the cost effective Spantech designs to provide satisfactory protection for their contents and prevent propagation to adjacent storehouses in the event of an accidental explosion occurring within the NATO inter magazine safety distances.

The trials were conducted by the Australian Department of Defence in conjunction with the United Kingdom Ministry of Defence and a division of the United States Army Corps of Engineers.

The Spantech ESH is now the benchmark for ESH projects undertaken by the Australian Department of Defence, Ministry of Defence, New Zealand and many others.

Test Overview

The key stages of the tests were:

Stage I

Three Spantech 13m ESH (receptors) were constructed at D3 and D4 distances from a UK Double Bay Igloo donor.

The donor contained 75,000kgs (NEQ) of HD 1.1 and was wired at 600 points for instantaneous detonation.

All three Spantech 13m ESH receptor buildings survived.

Stage II

Three Spantech 13m ESH (receptors) were subjected to an open air blast with 75,000kgs (NEQ) of HD 1.1 placed on an adjacent concrete slab.  The stack was again wired at 600 points for instantaneous detonation.

All Spantech 13m ESH receptors survived.

Stage III

A Spantech 13m ESH (donor) was filled with 75,000kgs (NEQ) of HD 1.1 wired at 600 points for instantaneous detonation.

A new Spantech 23m ESH (receptor) was constructed for Stage III. The design included an internal double arch stepped to allow additional pallet storage in the rear wall.

All receptors survived.

Stage IV

A Spantech 13m ESH (donor) was subjected to a series of HD 1.2 burns. The largest burn featured over five thousand 105mm shells in a stack comprising 160 pallets.

The donor building suppressed the series of explosions and all Spantech buildings survived.


The Australian Ordnance Council advised, “the Spantech 13m and 23m Spantech Explosives Storehouse designs are acceptable for use and qualified for use as Bar 7 igloos.”

In particular:

  • During all stages of testing the Spantech ESH survived the force of the blast and proved to be able to satisfactorily protect the contents to a serviceable standard.
  • The fragmentation spread of the Spantech ESH was significantly lower than comparable structures, with the fragmentation spread remaining within the recommended NATO safety guidelines.

International Acceptance

Since the successful testing Spantech has constructed over 500 Spantech ESH and other blast resistant defence buildings.

The Spantech 13m ESH and Spantech 23m ESH are now specified and widely used by Defence departments in Australia, New Zealand, the United Arab Emirates and Malaysia.

For more information download the Spantech Defence brochure.

Other Defence Buildings

Also refer to:

Sample Defence Projects