An automotive component plant is not one facility but several risk profiles under one roof: machining with cutting oils, hydraulic presses, welding cells, aluminium die casting, heat treatment, a paint line and high-bay parts storage. OEM supplier specifications and insurer requirements often push the protection level above the regulatory minimum.
Hazard classification: NFPA 13 and EN 12845
In the NFPA 13 example lists, metalworking and machine shops are OH2, areas using combustible hydraulic fluids and die casting are EH1, and open oil quenching is EH2. Under EN 12845 Annex A, metalworking is usually OH1–OH2, while paint application and plastic part manufacture sit higher. The final class depends on process and oil inventory.
| Area | NFPA 13 (typical) | EN 12845 (typical) | Note |
|---|---|---|---|
| Machining, assembly | OH2 | OH1–OH2 | Cutting oil and plastic part quantity |
| Hydraulic press line | EH1 (combustible fluid) | OH3–HHP | Less-flammable fluid may lower the class |
| Aluminium die casting | EH1 | OH3–HHP | Molten metal and water contact |
| Heat treatment, oil quenching | EH2 (open oil quench) | HHP | Local protection over tanks |
| Paint line and booths | EH2 + NFPA 33 | HHP + special system | Booth, duct and filter protection |
| Parts and packaging store | Storage criteria | Storage criteria | Plastic totes and parts decide |
For a first pass use the NFPA 13 hazard classification tool and the EN 12845 hazard class finder.
Process-by-process system selection
Hydraulic presses and power units
A leak from a high-pressure hydraulic line that sprays onto a hot surface creates a spray fire. Measures:
- Where possible, use an approved less-flammable hydraulic fluid; this substantially reduces the protection requirement.
- Sprinklers in press pits and around power units, with local foam-water if needed.
- Automatic shutdown of the hydraulic pump on fire detection.
Machining and CNC
- In-machine CO₂ or similar local suppression for enclosed machines using oil-based coolant.
- Cleaning of deposits in oil mist extraction ducts, with in-duct protection where needed.
Casting and metal dust
- Molten metal zones carry a water contact risk; plan sprinkler layout and drainage accordingly.
- Explosion measures for aluminium and magnesium dust and swarf collection: aluminium casting (NFPA 484) and metal dust (NFPA 484).
Paint line
Booths, exhaust ducts, filters and the paint mixing room need their own protection: automotive spray booths (NFPA 33). Booth sprinklers must be protected against overspray.
Welding cells
Sparks from robotic welding cells ignite nearby plastic totes and cable trays. Limits on combustibles around the cell and a hot work permit procedure (NFPA 51B) matter as much as sprinklers.
Storage
Metal parts stored in plastic totes pull the commodity class towards plastics. ESFR is common in high-bay racking; check suitability with the ESFR suitability checker. More detail: logistics warehouse fire protection. If EV components or lithium-ion cells are stored, a separate risk assessment is needed: lithium-ion battery fires.
Water supply and pumps
- The governing scenario is usually the ESFR store or the paint line; whether two scenarios must run at once is decided by risk analysis.
- Tank volume: fire water tank sizing; diesel pump fuel: diesel fire pump fuel tank calculator.
- Industrial estate mains are often not accepted as a reliable source; a dedicated tank and pump set is normal. Check suction with the NPSH calculator.
- Include the hydrant ring and foam firefighting capability (for paint and oil areas).
Detection, alarm and smoke control
- Large production halls: beam or aspirating smoke detection, with devices suited to dusty and oil-mist zones.
- Paint booths and press pits: flame detection or the system's own detection; conveyor, fan and pump interlocks on discharge.
- Smoke ventilation: roof vents and smoke curtains divide the hall into reservoirs; for an initial size use the smoke vent area calculator. Where vents are combined with ESFR, choose the opening logic (heat-operated or delayed) so it does not impair sprinkler performance.
- Sprinkler monitoring: zone valves, flow switches and pump status reported to the fire panel and the plant SCADA.
Turkey: points under the BYKHY
The BYKHY sets sprinkler requirements for industrial buildings by hazard class, compartment area and quantity of flammable materials, with additional provisions for paint and solvent stores. OEM supplier specifications and insurers usually ask for NFPA or FM Global based design.
Common site mistakes
- Press lines protected at general machining density. Hydraulic spray fires are ignored.
- Hydraulic pumps keep running in a fire. No interlock.
- Booth sprinklers coated in paint. Protective bags are not fitted or not replaced.
- Parts in plastic totes classified as metal parts.
- Crane runways and conveyors obstructing sprinklers. Conveyors added later leave unprotected areas below.
- Swarf and oil build-up. Under machines and inside ducts.
- Fire design not updated when lines are added. New lines run on the old hydraulic calculation.
Design checklist
| Check | What to look at |
|---|---|
| Classification | Machining, presses, casting, heat treatment, paint and storage separately |
| Hydraulic fluid | Fluid type, press pit protection, pump interlock |
| Paint line | Booth, duct, filters, mixing room; NFPA 33 |
| Metal dust | Dust collection explosion measures, NFPA 484 |
| Storage | Plastic tote effect, ESFR suitability, in-rack need |
| Obstructions | Protection under crane runways, conveyors and platforms |
| Water supply | Governing scenario, tank, pump redundancy, hydrants |
| Detection and smoke | Hall detection, vent logic, SCADA reporting |
| Management of change | Design revision for every new line or layout change |
In automotive supply, the fire design is a living document. Model changes alter line layouts, storage heights and tote types. Every layout change should trigger a fresh check of the fire protection.
Frequently Asked Questions
What hazard class is a hydraulic press line?
In the NFPA 13 examples, areas using combustible hydraulic fluids are around EH1. An approved less-flammable fluid can reduce the requirement; decide together with the insurer.
Are sprinklers enough for a paint line?
No. Booths, exhaust ducts, filters and the mixing room are protected separately following NFPA 33, with detection and conveyor and fan interlocks as part of the system.
How are metal parts in plastic totes classified?
Because the tote is combustible, the commodity class shifts towards plastics. Even if the parts do not burn, protection is chosen by tote material and arrangement.
Can smoke vents be used with ESFR?
Yes, but the vent opening logic must be chosen so it does not impair sprinkler performance. Confirm this against the standard and the insurer's requirements.
SprinkCalc — Fire Sprinkler Design Across Three Standards
SprinkCalc covers hazard classification, design density and area, K-factor selection, water demand and hydraulic calculations for NFPA 13, FM Global and BS EN 12845 in a single iOS app, and exports a professional PDF report.
Download SprinkCalc on the App StoreNFPA 13, NFPA 33 (spray application), NFPA 484 (combustible metals), NFPA 51B (hot work), NFPA 72, NFPA 204 (smoke venting), EN 12845, FM Global data sheets (hydraulic fluids, storage), Turkish BYKHY. Confirm values against the current edition and the insurer. The findings here are typical defect patterns, not an account of events at any particular site.