4.18 [RD021] [CUP Sprinkler 3mm] [LPCB, VdS, CE] - Brass LR.jpg 4.18 [RD021] [CUP Sprinkler 3mm] [LPCB, VdS, CE] - Black LR.jpg

RD021 CUP Conventional Sprinklers Quick Response

  • LPCB Logo Mid grey 566d-02.jpg
  • VdS Logo mid grey 2.jpg
  • CE Logo Mid Grey 144.jpg
  • SBSC Grey.jpg
  • gost logo 300.jpg
K factor 80 (5.6)
Standard Orifice Size 15mm (½”)
Standard Thread Size ½” NPT
Response Quick Response
Bulb 3mm
Maximum Working Pressure 12.1 bar (175 psi)
Finish Brass, chrome and white paint finish. Special RAL colours available on request
Approvals LPCB, VdS, CE, SBSC, Gost

The Rapidrop model RD021 are Conventional, Quick Response frangible glass bulb automatic sprinklers. CE marked, VdS and LPCB approved .
They are standard orifice fire sprinklers for installation in fire sprinkler systems designed in accordance with standard installation rules, e.g. EN12845 or the requirements of the authority having jurisdiction.
Conventional sprinklers produce a spherical water discharge pattern. In a fire condition the heat causes the fluid in the glass bulb to expand which shatters the glass
and releases the spring seal assembly. Water flows from the orifice onto the sprinkler deflector which diffuses the water into a uniform spray pattern which extinguishes or controls the fire.

K factor K80 (K5.6)
Standard Office Size 15mm (½”)
Thread Size ½”NPT
(R½” – ½”BSPT available on special order
Max. Working Pressure 12 bar (175 psi)
Min. Operating Pressure 0.5 bar (7psi)
Factory Pressure Test 100% at 34 bar (500 psi)
Weight 57grams (2oz.)
Fitted with Bulb Protector Remove after installing sprinkler

Operating Temperatures

Nominal Operating Temperature Bulb Colour
57ºC (135ºF) Orange
68ºC (155ºF) Red
79ºC (175ºF) Yellow
93ºC (200ºF) Green
141ºC (286ºF) Blue


RD021 Design Coverage 

Conventional for installing in pendent or upright position giving a spherical discharge with a proportion of water being thrown upwards towards the ceiling. For sprinkler coverage area and placement refer to NFPA 13 standards or other installation rules for automatic sprinkler systems as required by the authority having jurisdiction.  The following details are provided for information only.

Rapidrop RD021 CUP Fire Sprinkler HeadRD021 CUP Sprinkler Design Coverage


Rapidrop K80 (K5.6) Sprinkler Flow Characteristics


Minimum Operating Pressure K80 Sprinkler Heads