In brief
In yarn, fabric and garment warehouses, fire grows quickly because of porous material with a large surface area, packaging and high stacks. Fire load increases with the mass and calorific value of the stored material; doubling the stack height in the same area doubles the load. Fibre dust building up on the ceiling, light fittings and motors allows fire to spread along surfaces. Because a sprinkler system is designed for a specific stack height, it will not work as designed if the stacking limit and the clearance below the heads are not maintained.
Why does a textile warehouse fire grow so fast?
In textiles, one of Bursa's dominant sectors, the warehouse often covers an area as large as production: yarn bobbins, fabric rolls, cartons of garments, packaging material. What increases textile warehouse fire risk is the common properties of these materials:
- Large surface area and porosity: Fibre, yarn and fabric have a large surface in contact with air; flame spreads quickly across an ignited surface.
- Packaging: Cardboard cartons, stretch film and plastic bags add extra fuel to the fire.
- High stacks: Material piled vertically lets flame accelerate upwards and reach the ceiling.
- Accumulated fibre dust: Fibres suspended in the air in production and storage settle on surfaces over time and carry fire through the warehouse.
This article focuses on the warehouse. For the fire risk of stenter machines in finishing plants, see our article on stenter machine fire risk, and for weaving halls, OHS in weaving businesses.
How is textile fire load calculated?
The Regulation on the Protection of Buildings from Fire (BYKHY) defines fire load as the sum of the mass of each combustible material in a compartment multiplied by its net calorific value, divided by the total floor area of that compartment. Its unit is MJ/m².
Fire load = Σ (mass × net calorific value) / floor area
The Regulation classifies occupancies as low, medium and high hazard according to fire load and combustibility (Art. 19). In Annex 1/B, cotton spinning mills and fabric and clothing factories are listed in the medium hazard group. The capacities of the fire water tank, pumps and extinguishing systems are determined according to this classification.
The practical lessons of the calculation are clear even without figures:
- Stack height directly increases the load. In the same 1,000 m² area, if stacks rise from 3 metres to 6 metres, the stored mass, and therefore the fire load, roughly doubles. The extinguishing system, however, may have been designed for the load in the first case.
- The type of material matters. The calorific value of polyolefin-based fibres such as polypropylene is markedly higher than that of cellulose-based fibres such as cotton. When the product mix in the warehouse changes, the fire load changes too.
- Packaging counts. Cartons and plastic packaging can create as much fire load as the product itself.
The calorific values for a real calculation are taken from the material's technical data and the fire protection design. When the use of the warehouse changes (a yarn store becomes a garment store, stacks rise), whether the fire protection design covers this use should be reassessed.
Fibre dust build-up: the invisible fuel
Fibre dust is the most commonly underestimated fire source in textile facilities. Airborne fibres settle on roof trusses, cable trays, the tops of light fittings, motor cooling fins and the engine compartments of forklifts. This accumulated layer can ignite from a small spark, and the flame races along the surface and spreads through the warehouse.
To manage fibre dust build-up:
- Write a cleaning schedule. It should be clear which areas, including high surfaces, are cleaned how often, by whom and how it is recorded.
- Use vacuum instead of compressed air. Blowing with compressed air lifts dust into the air and carries it to other surfaces.
- Clean heated surfaces first. The tops of light fittings, motors, panels and chargers are where build-up can ignite.
- Check forklifts at the end of the shift. Fibre packed into the engine compartment and around the exhaust comes into contact with hot surfaces.
- Carry out an explosive atmosphere assessment. If fine dust concentrates in the air, the explosive atmosphere risk is assessed in the ATEX document. For the mechanism of dust explosions, see our article on dust explosion risk.
Stack height and sprinkler clearance
Art. 96 of the BYKHY lists the buildings where an automatic sprinkler system is mandatory. Annex 8/B of the Regulation states that TS EN 12845 is to be used as the basis for sprinkler design in storage areas and occupancies with different characteristics. We covered which warehouses fall within the scope of sprinklers in our article on sprinkler requirements.
A yarn warehouse sprinkler system works for the stack height and arrangement it was designed for. This assumption is what most often breaks down on site:
| Checkpoint | Why it matters | Recommended check |
|---|---|---|
| Maximum stack height | Sprinkler design is based on a specific stack height | Mark the design value with a line on racks and walls |
| Clearance below sprinkler heads | Water distribution must reach the top of the stack unobstructed | Maintain the clearance set in the design and standard; do not stack up to the ceiling |
| Covers on top of racks | Plastic or tarpaulin covers stop water reaching the stack | No covers are laid on top of racks |
| Changes to rack layout | A new rack can invalidate the existing sprinkler layout | Consult the fire protection designer before changing racks |
| Aisles and access | Access to hydrants, hose reels and extinguishers | Kept marked and clear |
| Heat sources | Light fittings and heaters must not touch the stack | A gap is left between stacks and light fittings |
The numerical value of the clearance to be left between the sprinkler head and the top of the stack, and of the maximum permitted stack height, depends on the standard the system is based on and the design calculation. So take the value not from a general rule but from your warehouse's approved sprinkler design, and give it to the warehouse manager in writing. For the safety of the racking system itself, see our article on industrial racking safety.
Fire installations (extinguishing, sprinklers, hydrants, detection) are subject to periodic inspection at least once a year under Annex III of the Regulation on Work Equipment. You can enter inspection dates into the OHS calendar tool.
Separate ignition sources
There is always fuel in a warehouse; what can be done is to separate ignition sources from the fuel:
- Electrical: Panels, socket groups and cable trays are checked regularly; no material is stored in front of or around panels.
- Charging area: Forklift and pallet truck charging is done in an area separate from stored material. For risks specific to lithium batteries, see our article on lithium battery charging area safety.
- Hot work: Jobs such as rack installation, roof repairs or welding do not start without a hot work permit; a fire watch is kept after the work is finished.
- Packaging machines: Shrink tunnels and heat-sealing machines are positioned away from stacks.
- Smoking and heaters: No smoking in the warehouse; no portable heaters.
Fire training and the emergency plan
Because fire grows quickly in a textile warehouse, the emphasis of the emergency plan is on early detection and fast evacuation. Specific to the warehouse, the plan should state that escape routes must not be narrowed by stacks, that fire doors must be kept clear, how a fire will be detected in an empty warehouse at night and at weekends, and through which gate the fire brigade will enter. For the general structure of the plan, see our article how to prepare an emergency plan.
Art. 129 of the BYKHY requires teams to be trained in fire prevention, extinguishing, rescue and first aid, and at least one extinguishing and evacuation drill to be held in buildings each year. The most valuable training for warehouse staff is learning hands-on how to use an extinguisher on a real fire and when to stop and evacuate. We include this practice in our theoretical and practical fire training, and we prepare a warehouse-specific plan through our fire training and emergency plan services. For other risks in the textile sector, see our textiles page.
Frequently Asked Questions
How high can stacks be in a fabric warehouse?
There is no single general limit. In a warehouse with sprinklers, the maximum stack height is set in the sprinkler design prepared according to the standard the system is based on. Take this value from the design, mark it on racks and walls, and make ensuring it is not exceeded a written duty of the warehouse manager.
Can fibre dust be cleaned with compressed air?
It is not recommended. Compressed air lifts dust into the air, carries it to other surfaces and can create an ignitable dust cloud. Vacuum cleaning and a regular cleaning schedule are preferred.
How can the fire load of a textile warehouse be reduced?
Limiting stack height, separating packaging material from the storage area, reducing excess stock and dividing the warehouse into separate areas with fire compartments reduce the fire load or the area over which a fire can grow. When the use changes, the fire protection design needs to be reassessed.
How often are drills held in a warehouse?
Under Art. 129 of the BYKHY, at least one extinguishing and evacuation drill is held in buildings each year. The drill under the emergency plan is also held at least once a year, and a drill form is completed.
Fire classes, choosing the right extinguisher, hands-on extinguishing in a safe open area and an evacuation drill, all in one training.
Bursa SİSTEMER OSGB Technical Team — written from the field experience of our OHS specialists and workplace physicians. Legal information is valid as of the publication/update date; contact us for an assessment specific to your business.