Logistics Warehouse Sprinkler Systems
Automatic fire extinguishing systems in logistics warehouses adopt standards and mechanisms significantly different from general office buildings to prevent the rapid spread of fire fueled by high ceilings and massive quantities of stored goods (cardboard, plastics, etc.).
A sprinkler head is automatically activated when the heat-sensitive part melts or bursts upon reaching a certain temperature (primarily around 72°C to 96°C), allowing pressurized water in the piping to spray out.
Basic Types of Sprinkler Systems
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Closed Wet-pipe (Most Common):
The piping is constantly filled with pressurized water, and water is discharged immediately when a head opens due to the heat of a fire. It is a highly reliable system with a simple structure. -
Closed Dry-pipe (For cold storage/cold regions):
To prevent freezing, the piping is filled with compressed air; when a head opens, the air is released first, followed by the supply of water. -
Pre-action (To prevent accidental discharge):
A mechanism that discharges water only when both the detection by a fire detector and the activation of a sprinkler head occur. It is introduced in warehouses where one wishes to avoid water damage to cargo as much as possible.
Installation Points Unique to Logistics Warehouses
| Installation Method | Overview and Main Purpose |
|---|---|
| In-rack Sprinklers | In high-rise rack warehouses (shelving warehouses), water from ceiling installations alone will not reach the lower tiers, so this method incorporates heads into each tier of the racks. |
| ESFR (Early Suppression Fast Response) | Sprinklers that blast large volumes of large water droplets at high speed directly at the fire source. It can sometimes eliminate the need for in-rack piping, offering flexibility for layout changes. |
| Criteria for Ceilings Exceeding 10m | In large-space warehouses with high ceilings, it takes time for heat to reach the ceiling in the initial stages, making highly sensitive heads and linked detectors mandatory. |
In logistics facilities, the requirements under the Fire Service Act change significantly depending on whether the stored goods fall under "designated combustibles," as well as the height and layout of the racks.
Fundamental Differences in Approach by System (In-rack vs. ESFR)
Both in-rack sprinklers and ESFR (Early Suppression Fast Response) sprinklers are used as fire countermeasures in high-rise logistics warehouses, but their "approach to fire" and "warehouse usability/cost" differ greatly.
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In-rack Sprinklers:
Sprinkler heads are placed on each tier of the racks (shelves) to extinguish the fire locally from the position closest to the source. While it can reliably discharge water onto the fire source even with high ceilings, it requires piping to be run throughout every shelf. -
ESFR Sprinklers:
Installed only on the ceiling, they react to the heat of the initial fire at ultra-high speed (the heat-sensitive element is thin and responds quickly). They force a large volume of large water droplets through from the ceiling with intense momentum to crush the fire source on the floor or inside the racks in its early stages (the goal is "suppression/extinguishing" rather than "control").
Major Comparisons (Specifications, Cost, Workability)
| Comparison Item | In-rack Sprinklers | ESFR Sprinklers |
|---|---|---|
| Installation Location | Ceiling + Inside each tier of racks | Ceiling only |
| Extinguishing Mechanism | Heads near the fire source activate individually for local extinguishing | Blasts large volumes of large water droplets from the ceiling |
| Layout Changes | Difficult (Piping work is required when removing/moving racks) | Easy (The floor becomes free space) |
| Water Damage Risk | Tends to be limited only to the area around the fire source | Due to the large volume of water discharged, the area getting wet is wide, including the surroundings |
| Pump/Water Source Equipment | Standard | Requires ultra-high pressure/large volume pumps and large water tanks |
| Initial Cost | Piping labor is extremely high, making construction costs relatively expensive | Piping length is short, but the cost for large-volume pumps and water sources is high |
| Maintainability | High effort for maintaining piping and dealing with head damage from cargo contact | Because they are only on the ceiling, daily management effort is low |
Which Should You Choose?
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Cases where ESFR is suitable:
- Logistics warehouses where there is a possibility of layout changes in the future, such as rearranging racks or introducing automated guided vehicles (AGVs, etc.)
- Rental logistics facilities (multi-tenant type) with ceiling heights up to about 12m to 13.7m
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Cases where In-rack Sprinklers are suitable:
- Extremely tall fixed automated warehouses (e.g., heights exceeding 15m, which exceed the limits of ESFR)
- When the installation space for pump equipment and receiving tanks is limited, making it impossible to install large-volume equipment for ESFR