Risk Attribute

Compressed Gas Cylinder Storage

Expert-reviewed Updated: 2026-09-03 Expert-reviewed: 2026-09-04 (Guido Hesse, Hesse Group Holding AG) Version 0.1.0

Compressed gas cylinder storage records the number and type of compressed, liquefied or dissolved gas cylinders held on site, as queried in property insurance proposal forms.

Category
Hazardous materials · Stück/units
Data type
Number
Risk drivers
Severity, Accumulation
Underwriting impact
Premium, Condition/Warranty, Sublimit

Typical proposal-form questions

  • How many compressed, liquefied or dissolved gas cylinders are stored on site, and of which gas types (flammable, oxidising, toxic, inert)?
  • Is storage located outdoors, in a dedicated ventilated enclosure, or inside production and storage buildings?
  • Are flammable and oxidising gases segregated, and are cylinders secured against falling and protected from heat sources?

Evidence

  • Gas cylinder inventory with gas types and quantities
  • Storage area layout and ventilation documentation
  • Segregation and cylinder-securing procedure

Why it matters for underwriting

Compressed gas cylinders combine a fire and explosion hazard with a projectile risk: a cylinder exposed to fire can fail catastrophically and become a missile capable of penetrating walls and injuring occupants over a wide radius, while flammable or oxidising gas releases can rapidly intensify an existing fire. Underwriters need the number, gas type and storage arrangement to gauge the accumulation exposure at a single location and to judge whether the site’s fire protection concept adequately addresses this specific hazard.

Capturing the attribute and evidence

Proposal forms ask how many cylinders are stored on site and of which gas type, distinguishing flammable, oxidising, toxic and inert gases, together with whether storage is outdoors, in a dedicated ventilated enclosure, or inside occupied buildings. Underwriters corroborate the declaration with the gas cylinder inventory, the storage area layout and ventilation documentation, and evidence of segregation between incompatible gas classes and of physical securing against cylinders falling; larger inventories typically prompt a risk engineering survey.

Effect on coverage, premium and conditions

Small quantities stored outdoors in a segregated, secured and well-ventilated area generally attract standard rating. Larger inventories, storage of flammable gases near occupied buildings, or mixed storage of incompatible gas classes commonly result in premium loadings, fire sublimits, or conditions requiring segregation, securing and distance from ignition sources; significant undeclared quantities discovered during survey can lead to condition breaches or requirement for immediate remediation before cover continues.

Mitigation measures

Recommended measures include storing cylinders outdoors or in a dedicated, well-ventilated enclosure away from occupied buildings, segregating flammable and oxidising gases from each other and from combustible materials, securing cylinders upright against falling with chains or stands, and protecting storage areas from heat sources and direct sun exposure.