Technical terms in fire protection and piping are used in English in specifications and drawings, and in Arabic on site and in correspondence, and translations vary from person to person. This glossary gathers 71 common terms with one consistent Arabic equivalent and a one-line definition, in four groups.
Key points
- 71 terms on valves, grooved fittings, systems, and approvals and testing.
- The Arabic equivalent is the one used throughout our guides and product pages.
- Each main term has a detailed guide in our technical library.
Valves
| Term | Arabic | Definition |
|---|---|---|
| Gate valve | محبس بوابة | Opens and closes with a gate moving across the flow; used for full isolation. |
| OS&Y (Outside Screw & Yoke) | محبس بوابة بعمود صاعد | The thread is outside the body and the stem rises on opening, so its position is visible. |
| NRS (Non-Rising Stem) | محبس بوابة بعمود ثابت | The stem does not rise; used with an indicator post or supervisory switch. |
| Resilient wedge / seat | بوابة مغلّفة بالمطاط | A rubber-encapsulated wedge that seals without a cavity at the bottom. |
| Butterfly valve | محبس فراشة | A disc that turns a quarter turn; light and short face to face. |
| Check valve | محبس عدم رجوع | Lets water pass in one direction only. |
| Swing check valve | محبس عدم رجوع متأرجح | A hinged disc that swings open with the flow. |
| Wafer check valve | محبس عدم رجوع ويفر | A thin valve clamped between two flanges. |
| Alarm check valve | محبس الإنذار | A check valve that triggers an alarm when water flows in a wet system. |
| Deluge valve | محبس غمري | Opens on a signal to supply a network of open sprinklers. |
| Pressure reducing valve (PRV) | محبس خفض الضغط | Reduces outlet pressure to a set value. |
| Pressure relief valve | محبس تنفيس الضغط | Opens to discharge water when a set pressure is exceeded. |
| Y-strainer | مصفاة Y | Traps debris ahead of valves and equipment. |
| Ball valve | محبس كروي | A bored ball turned a quarter turn; common in small sizes. |
| Test and drain valve | محبس الاختبار والتصريف | Used to test a floor’s flow and drain the system. |
| Post indicator valve (PIV) | محبس بعمود مؤشر | A buried valve operated from an above-ground post that shows its position. |
| Wall indicator valve (WIV) | محبس بمؤشر جداري | Operated from an indicator mounted on a wall. |
| Air release valve | محبس تنفيس الهواء | Expels air trapped in the pipework. |
Grooved fittings and couplings
| Term | Arabic | Definition |
|---|---|---|
| Grooved coupling | جلبة محززة | A two-piece housing and gasket joining two grooved pipe ends. |
| Rigid coupling | جلبة ثابتة | Prevents movement between pipes, behaving like a weld. |
| Flexible coupling | جلبة مرنة | Allows limited deflection and expansion. |
| Reducing coupling | جلبة نقاص | Joins two pipes of different sizes. |
| Mechanical tee | قسام ميكانيكي | Takes a branch from a run pipe through a drilled hole, without welding. |
| Grooved flange adaptor | محوّل فلنجة محزز | Turns a grooved end into a flange to connect a valve or equipment. |
| End cap | سدة نهاية | Closes the end of a line. |
| Elbow | كوع | Changes line direction by 90°, 45° or another angle. |
| Tee | مشترك (تي) | Takes a branch at a right angle. |
| Concentric reducer | نقاص متحد المركز | Transitions between two sizes on the same axis. |
| Eccentric reducer | نقاص لامركزي | Transitions between sizes with one flat side; prevents air pockets. |
| Gasket | جوان (حلقة إحكام) | A rubber ring that seals the joint; usually EPDM for water. |
| Roll grooving | تحزيز بالدرفلة | Forms the groove by pressing, without removing metal. |
| Cut grooving | تحزيز بالقطع | Forms the groove by removing metal from the pipe wall. |
| Ductile iron | حديد مرن (دكتايل) | Cast iron with spheroidal graphite; stronger and less brittle. |
| Malleable iron | حديد قابل للطرق | The usual material for black and galvanised threaded fittings. |
| NPT / BSPT | سن أمريكي / سن بريطاني | Two tapered pipe thread standards; not interchangeable. |
Systems and components
| Term | Arabic | Definition |
|---|---|---|
| Wet pipe system | نظام رطب | Pipes are always full of water. |
| Dry pipe system | نظام جاف | Pipes hold compressed air; for areas exposed to freezing. |
| Pre-action system | نظام سابق التشغيل | Fills with water after a detector signal. |
| Deluge system | نظام غمري | Open sprinklers that all discharge together. |
| Sprinkler | رشاش | Opens with heat and spreads water over a set area. |
| K-factor | معامل K | Relates sprinkler flow to pressure: Q = K × √P. |
| Riser | صاعد | The vertical pipe that feeds the floors. |
| Cross main | خط رئيسي أفقي | Feeds the branch lines. |
| Branch line | خط فرعي | The line on which sprinklers are installed. |
| Fire pump | مضخة حريق | Raises water pressure to supply the system. |
| Jockey pump | مضخة موازنة الضغط | A small pump that maintains system pressure. |
| Fire department connection (FDC) | وصلة الدفاع المدني | Lets fire engines feed the system from outside. |
| Fire hydrant | حنفية حريق | An outdoor water outlet for fire crews. |
| Landing valve | محبس خرطوم | An outlet for a fire hose inside the building. |
| Water flow indicator / flow switch | مؤشر تدفق المياه | Sends a signal when water flows in the pipe. |
| Supervisory (tamper) switch | مفتاح مراقبة | Alerts if an isolation valve’s position changes. |
| Pressure switch | مفتاح ضغط | Operates when pressure reaches a set value. |
| Anti-vortex plate | مانع الدوامة | A plate at the suction outlet that prevents an air vortex. |
| Puddle flange | فلنجة عبور (بادل فلانج) | A flange on a pipe passing through a concrete wall to stop leakage. |
| Hazard classification | تصنيف الخطورة | Classing an area (light, ordinary, extra) to set water density. |
| Design density | كثافة التصميم | Water quantity per unit area. |
| Hydraulic calculation | حسابات هيدروليكية | Calculating pressure and flow to confirm the supply is adequate. |
Approvals and testing
| Term | Arabic | Definition |
|---|---|---|
| UL Listed | مدرج لدى UL | Tested by UL and shown in its listings for a specific use. |
| FM Approved | معتمد من FM | Tested and approved by FM Approvals. |
| Submittal | ملف اعتماد المواد | Documents submitted to the consultant to approve a material. |
| Compliance statement | بيان المطابقة | A table comparing the specification with what the material offers. |
| Working pressure | ضغط التشغيل | The highest rated pressure for continuous use. |
| Hydrostatic test | اختبار هيدروستاتيكي | Testing the network with water above working pressure. |
| Flushing | غسيل الشبكة | Running water through to remove debris before service. |
| ITM | الفحص والاختبار والصيانة | The periodic maintenance programme under NFPA 25. |
| AHJ (Authority Having Jurisdiction) | الجهة المختصة | The body with approval authority, such as Civil Defense. |
| PN16 | ضغط اسمي 16 بار | A European pressure rating for valves and flanges. |
| Class 150 / Class 125 | فئة 150 / فئة 125 | American pressure classes for flanges. |
| DN (Nominal diameter) | القطر الاسمي | A number that names the size, not a measured diameter. |
| OD (Outside diameter) | القطر الخارجي | The pipe’s actual outside diameter. |
| Schedule (Sch) | سماكة الجدار (سكجول) | A number that indicates pipe wall thickness. |
Note
When writing a specification or submittal in Arabic, put the English term beside the Arabic on first mention, so the designer, supplier and inspector read it the same way.
Frequently asked questions
What is the difference between DN and outside diameter?
DN is a nominal size number; the outside diameter is the actual measurement. For example DN100 corresponds to 4″ with an outside diameter of 114.3 mm. See the size converter.
Are OS&Y and NRS different kinds of valve?
Both are gate valves; the difference is how the stem moves. See the detailed comparison.
What is the difference between UL Listed and FM Approved?
They are two independent bodies that test and approve products. See how to verify approval.
References
- NFPA 13 — Standard for the Installation of Sprinkler Systems.
- NFPA 25 — Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems.
- SBC 801 — Saudi Fire Code.
Definitions are shortened for clarity; the formal definition of each term is in its own standard.
Part of a complete guide
This article is part of The Complete Guide to Sprinkler Systems in Saudi Arabia: Types, Components and Testing.
