Article 94(b)(5) of the Turkish Regulation on Fire Protection of Buildings (BYKHY) requires a design flow of 100 l/min and a design pressure of 400 kPa for hose reels with a round semi-rigid hose and no fire brigade outlet inside; if the pressure at the nozzle inlet exceeds 900 kPa, a pressure reducer is used. The same article limits the semi-rigid hose length to 30 m, gives separate values for layflat hose cabinets (400 l/min, at least 400 kPa, at most 20 m) and sets the 60 m reach rule for the fire brigade outlet line.
The two installations of Article 94
Article 94(1) defines two installations inside the building: the fire brigade outlet line (for fire brigade personnel and trained staff) and hose cabinets (for the occupants of the building to control a small fire).
Fire brigade outlet line (Article 94(a))
| Rule | Value | Paragraph |
|---|---|---|
| Where mandatory | High-rise buildings; shopping centres, car parks and similar with a floor area of more than 1,000 m² | 94(a)(1) |
| Location of the outlets | Protected spaces such as an escape stair or a fire lobby | 94(a)(1) |
| Floors with one dimension exceeding 60 m | A hose cabinet and a fire brigade outlet are provided (Guide explanation: in the whole structure) | 94(a)(1) |
| Distance to an outlet | At most 60 m from any point | 94(a)(2) |
| Hose connections | Storz type to fire brigade standards, 50 mm or 65 mm | 94(a)(3) |
| Connection point | If on the fixed pipework supplying the sprinkler and hose cabinet system, directly from the main risers | 94(a)(4) |
Hose cabinets (Article 94(b))
| Rule | Value | Paragraph |
|---|---|---|
| Hose length (hose reel with round semi-rigid hose in buildings without trained staff or fire brigade personnel, TS EN 671-1; hose TS EN 694, diameter 25 mm) | At most 30 m; the nozzle must be able to shut off, spray, jet or do all three | 94(b)(4) |
| Design flow (round semi-rigid hose, no fire brigade outlet) | 100 l/min | 94(b)(5) |
| Design pressure | 400 kPa | 94(b)(5) |
| Nozzle inlet pressure | Pressure reducer if it exceeds 900 kPa | 94(b)(5) |
| Layflat hose cabinet: where used and standard | In buildings required to employ trained firefighting personnel; TS EN 671-2 | 94(b)(6) |
| Layflat hose | Nominal diameter at most 50 mm, length at most 20 m; the nozzle must be able to shut off, spray, jet or do all three | 94(b)(6) |
| Layflat hose cabinet design flow and pressure | 400 l/min; at least 400 kPa | 94(b)(6) |
| Nozzle inlet pressure (layflat hose) | Pressure reducer if it exceeds 900 kPa | 94(b)(6) |
The 100 l/min value applies only to hose reels with a round semi-rigid hose. A layflat hose cabinet (Article 94(b)(6)) may be used in buildings required to employ trained firefighting personnel; its design flow is taken as 400 l/min and its design pressure as at least 400 kPa.
Link to the water tank
Article 92(6): where the only water-based extinguishing system in the building is hose cabinets, the water capacity in systems complying with TS EN 671-1 and 671-2 is the Article 94 design flows multiplied by the hazard class duration (30/60/90 min). If the use is not in the high hazard class and there are hose cabinets only, they may be connected to the building's domestic water system and no separate system is required; according to the Guide explanation, the Article 92(1) requirement of at least one reliable water source must still be met in this case. For layflat hose cabinets, the 400 l/min of Article 94(b)(6) is used as the flow.
Consistency check with Q = K x √P
The regulation does not define a K-factor; it gives the 100 l/min and 400 kPa values directly. The designer checks that at least 100 l/min is delivered at 400 kPa by applying Q = K x √P with the manufacturer's K value for the selected nozzle. The K value is taken from the manufacturer's data sheet; no K value is given in this article.
Field note
The two most common commissioning findings: 400 kPa not achieved at the most remote and highest hose reel, and no pressure reducer fitted on the lower floors even though 900 kPa is exceeded. Both are direct breaches of Article 94(b)(5); the hydraulic calculation report should show the most critical and the most favourable hose reel together.
Checklist
- Have 100 l/min and 400 kPa been calculated at the most critical hose reel (Article 94(b)(5))?
- Is there a pressure reducer on floors where pressures above 900 kPa occur?
- Does the semi-rigid hose not exceed 30 m (Article 94(b)(4)) and the layflat hose 20 m (Article 94(b)(6))?
- If there is a layflat hose cabinet, is the building required to employ trained firefighting personnel; does the cabinet comply with TS EN 671-2 and has it been calculated with 400 l/min and at least 400 kPa (Article 94(b)(6))?
- In a high-rise building or a shopping centre/car park above 1,000 m², are the fire brigade outlets in a protected space (Article 94(a)(1))?
- Is the distance from any point to an outlet at most 60 m (Article 94(a)(2))?
FAQ
What are the hose reel design flow and pressure under BYKHY?
Under Article 94(b)(5), hose reels with a round semi-rigid hose and no fire brigade outlet inside must have a design flow of 100 l/min and a design pressure of 400 kPa. If the pressure at the nozzle inlet exceeds 900 kPa, a pressure reducer is used.
Where is a fire brigade outlet line mandatory?
Under Article 94(a)(1), in high-rise buildings and in shopping centres, car parks and similar places with a floor area of more than 1,000 m², fire brigade connection outlets are left on a wet or dry fixed pipe system; these are located in protected spaces such as an escape stair or a fire lobby. The distance from any point to an outlet cannot exceed 60 m.
How is the water tank calculated for hose cabinets?
Under Article 92(6), if the building has hose cabinets only, the water capacity is found by multiplying the Article 94 design flow values by a duration of 30, 60 or 90 minutes according to the hazard class; if the use is not high hazard, the hose cabinets may be connected to the domestic water system.
References
- Turkish Regulation on Fire Protection of Buildings (BYKHY), Official Gazette 19.12.2007/26735 and amendments; Articles 92, 94 (94(a)(1)–(a)(4), 94(b)(4), 94(b)(5), 94(b)(6)). Amendments: OG 09/09/2009-27344; OG 05/04/2012-28255; OG 09/07/2015-29411; Council of Ministers Decision 2017/10459 of 14/06/2017 (in force 29/06/2017); Council of Ministers Decision 2018/11347 of 05/02/2018 (in force 15/03/2018); OG 04/11/2020-31294 (Presidential Decision 3167); OG 20/11/2021-31665 (Presidential Decision 4825); OG 01/07/2025-32943 (Presidential Decision 10026). Current text (mevzuat.gov.tr)
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Download MEP Calc on the App StoreSources are listed in the References section at the end of the article. Quotations from the regulation are unofficial English translations of the Turkish text. This article is for general information; for article numbers, thresholds and exemptions, the current regulation and standard texts published in the Official Gazette govern, and design must be carried out by an authorised engineer.