Are high-bay ASRS fire safe?

Yes, high-bay automated storage and retrieval systems (ASRS) can be fire-safe when fire protection is engineered as an integral part of the warehouse design. Automation alone does not establish fire safety. Achieving reliable protection requires coordinated engineering that accounts for stored products, rack geometry, suppression technology, and detection systems working together as a unified design.

The distinction matters because a high-bay ASRS introduces conditions that differ fundamentally from conventional flat storage. Storage heights can exceed 30 metres, airflow patterns within racks influence fire behaviour, and the density of stored goods creates challenges that off-the-shelf fire protection cannot address without careful analysis. Below, we examine how fire protection integrates into an ASRS, why warehouse configuration drives safety performance, and when fire protection planning should begin in a project.

How Is Fire Protection Integrated Into a High-Bay ASRS?

Fire protection in a high-bay ASRS is integrated through a combination of detection, suppression, and prevention measures that are engineered to match the specific storage arrangement, product characteristics, and building geometry. No single component provides adequate protection on its own; the system works as a coordinated whole.

Detection systems form the first layer. Smoke detection, linear heat detection, or aspirating systems are selected based on ceiling height, airflow conditions, and the types of products stored. In a high-bay environment, where ceilings may be 30 metres or more above the floor, detection technology must account for the time it takes smoke or heat to reach sensors and the dilution effects of large air volumes.

Suppression systems form the second layer. Options include wet-pipe or dry-pipe sprinkler systems and, in certain applications, oxygen-reduction systems. In-rack sprinklers are one integrated arrangement used to position suppression closer to stored goods rather than relying solely on ceiling-level activation. Full-scale research on rack-storage fire suppression by Xin et al. (2017) demonstrated that SMART sprinklers provided effective protection for a specified cartoned-plastic commodity in tested storage arrangements up to 12.2 metres high. These results confirm that suppression performance is validated for specific configurations, not assumed universally.

Equally important is the passive protection layer: fire-rated compartmentation, structural fire resistance of the racking itself, and the selection of non-combustible or fire-retardant materials where feasible. Maintenance programmes ensure that all active and passive systems remain operational throughout the warehouse lifecycle. Each of these elements must be designed in concert, because a change in one variable can affect the performance requirements of another.

Why Does Warehouse Configuration Affect Fire Safety Performance?

Warehouse configuration affects fire safety performance because storage height, rack geometry, product type, and packaging materials all influence how fire develops and how suppression systems respond. A fire protection design validated for one configuration does not automatically apply to another.

Storage Height and Rack Geometry

Storage height is one of the most significant variables. As height increases, the vertical flue spaces between stored units create chimney effects that accelerate upward fire spread. Research on sprinkler performance in rack storage by Kung et al. (2011) tested a K363 sprinkler across different discharge pressures, storage heights, ceiling clearances, and ignition positions. Results varied with test conditions, reinforcing that sprinkler performance is configuration-dependent. Rack depth, lane width, and the presence or absence of transverse flue spaces further shape fire dynamics and determine where suppression must be positioned to be effective.

Stored Products and Packaging

The products themselves matter as much as the structure that holds them. Paper rolls, steel coils, and finished tyres each present different fire hazard classifications. Paper and tyre products are combustible, while steel coils are not, but their packaging and dunnage may be. The commodity classification drives the required suppression density, the type of sprinkler head, and the spacing of in-rack protection. Packaging materials such as stretch wrap, cardboard, and wooden pallets add fuel load that must be accounted for in the fire protection design.

This is why fire safety performance cannot be assessed in isolation from the warehouse design. Every decision about rack configuration, product mix, and storage density has a direct consequence for the fire protection system that must serve it.

When Should Fire Protection Planning Start for an ASRS Project?

Fire protection planning should start at the earliest stage of ASRS project design, ideally during the concept and simulation phase, before rack geometry, building dimensions, and material flow layouts are finalised. Retrofitting fire protection into a completed design is more costly, less effective, and often requires compromises that reduce both safety and operational performance.

When fire protection engineers work alongside warehouse designers from the outset, suppression and detection requirements can influence rack spacing, building height, compartmentation, and material selection before these parameters are locked. This coordinated approach ensures that the automated storage system and its fire protection function as a single, optimised design rather than two competing systems forced to coexist.

Pesmel’s approach to fire-protection options for high-bay warehousing reflects this principle. Working in close cooperation with customers in the pulp and paper, steel and aluminium, and tyre manufacturing industries, Pesmel integrates fire protection considerations into the project verification and simulation process. This early coordination helps ensure that the final system meets both operational and safety objectives without unnecessary compromise.

If you are evaluating a high-bay ASRS investment, coordinate warehouse design and fire protection planning from the start. Contact Pesmel’s team to discuss how fire safety integrates into your specific material flow and storage requirements.