How high can an explosive storage box be stacked underground?

Answer: Two high in a chamber magazine, three in a surface room. The limit is lid clearance, not shell strength.

Can an explosive storage box stay at a holding point overnight?

Answer: Not recommended. Return the balance instead; a fence does not record who walked past it.

Do the two locks have to be different locks?

Answer: Yes. Two locks, two keys, two holders. One person with both is a single lock with extra steps.

Does the body need earthing?

Answer: Only with metal inserts, which take a single-point earth under 4 ohm; a plastic body is checked by surface resistance.

Will the latches seize in a dusty drift?

Answer: They stiffen as dust packs the pivot. Blow it out every two weeks instead of forcing the lever.

Explosive Storage Box Uses: Scenes, Setups and Handover

Quick answer: An explosive storage box appears in four places: the mine magazine, the tunnel or roadbed front, the temporary holding point, and the handover run. Four settings change between them: stacking height, floor and wall clearance, locks and seals, and ledger rhythm.

What the Box Does Inside a Mine Magazine
Tunnel and Roadbed Site Configuration
How to Lay Out a Temporary Holding Point
Handover and the Two-Lock Rule
Configuration Across Five Scenes
FAQ

1. What the Box Does Inside a Mine Magazine

A surface issue room sets the explosive storage box on a steel rack 100 mm off the floor, 200 mm from the wall. Underground, bodies stand in a single row, two high at most, 300 mm below the arch.

An 80 L body measures about 600 x 400 x 340 mm inside, which holds 24 kg of emulsion cartridges. It comes from approved stock divided by the box count, not from shell capacity; a 0.5 kg ledger gap means a recount.

Magazine type	Load per box	Stacking	Clearance
Surface issue room	24 kg max	3 high max	100 mm floor, 200 mm wall
Underground chamber	18 kg max	2 high max	150 mm floor and wall

The box keeps grades apart, one per lid, with a numbered seal across the latch and a desiccant pack weighed every two weeks.

2. Tunnel and Roadbed Site Configuration

A 3.5 m round on a tunnel face runs 60 to 90 kg in two draws. The explosive storage box sits 200 m back from the face, 50 m inside the portal, clear of vent ducts and cable trays, on 150 mm bearers levelled at all four corners.

Explosive storage box: three olive green bodies on outdoor stone, the front left one open showing grey foam dividers, the largest body behind right

Roadbed sections keep two or three holding points and move the box on a trolley without opening the lid. Two 8 mm pins through the base holes anchor it on a slope; above 85 percent humidity the gasket is replaced below 60 percent of its compressed thickness.

3. How to Lay Out a Temporary Holding Point

A holding point is not a magazine. It is where the explosive storage box waits between draws, so dwell time and supervision decide it.

Keep it 50 m from the face, 30 m from open flame, 20 m from distribution boards, combustibles cleared within 3 m. The ground is paved or takes 100 mm of compacted gravel, the body 200 mm clear.

Holding point	Maximum dwell	Distance to face	Supervision
Face point	one shift	200 m min in tunnel	named watch, key carried
Roadbed point	one shift	50 m min	watch or fenced lock

4. Handover and the Two-Lock Rule

Handover is where the explosive storage box changes custody and where the chain usually breaks. Two independent padlocks pass through two 10 mm bores on the front face, one held by the escort, one by the store, so neither party can open it alone. Keep the bores 60 mm apart, or the second shackle rides on the first.

Explosive storage box: black body close up, one stainless latch closed with fingerprints on the lever, textured rubber grip right, a second latch behind

Count the boxes, match seals and ledger, sign, then swap locks, all inside 30 minutes, before the vehicle moves. Below -20 C the gasket hardens, so warm the lid rim rather than prising it up.

5. Configuration Across Five Scenes

The shell does not change from magazine to transfer run; how it is placed, earthed and counted does. A body with metal inserts takes a single-point earth under 4 ohm; a plastic explosive storage box relies on surface dissipation between 10^6 and 10^9 ohm.

Scene	Locks and seal	Earthing	Ledger rhythm
Mine magazine	two locks plus seal	metal inserts earthed, 4 ohm max	daily count, weekly desiccant
Tunnel interior	two locks plus seal	earthed, quarterly surface test	signed at each shift
Roadbed point	two locks	quarterly surface test	logged per draw
Holding point	one lock plus fence	quarterly surface test	cleared same day

Conclusion

Four settings decide the layout: stacking height, base clearance, how many people hold keys, and how often the count is signed. Fix those first, then check wall thickness, latch count and gasket section against them. Ask where the explosive storage box will stand and who watches it.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.