Showing 0 products
Frequently Asked Questions
Do all the sprinklers go off at once in a fire?
No - each head operates individually when its own thermal element reaches its temperature.
The element is a glass bulb or a fusible link that holds a plug in the waterway.
Only heads exposed to enough heat operate, which in most fires is one or a small number.
That is why sprinkler water damage is far less than people expect, and far less than the fire would have caused.
Deluge systems are the deliberate exception: they use open heads and discharge from all of them at once when a detection system releases the valve.
The common belief comes from film and television rather than from how the technology works.
What does the colour of the glass bulb mean?
It indicates the temperature rating on most designs, and the colour coding is broadly consistent across manufacturers.
The bulb contains a liquid that expands as it heats until the bulb bursts.
Ratings are chosen so the head operates in a fire but not from the normal maximum temperature of the space.
Areas near heaters, in roof voids, in kitchens or in direct sun need higher-rated heads for that reason.
A head rated too low causes nuisance operation; too high delays operation in a real fire.
Fusible-link heads carry the same ratings, usually marked on the link or the frame rather than colour-coded.
What is the difference between quick-response and standard-response?
The speed the thermal element reacts, not the temperature it reacts at - they are separate properties.
A quick-response head has a thinner bulb or a more thermally sensitive link, so it absorbs heat faster.
That matters most where life safety is the objective and early operation keeps a room survivable.
Standard response is used where the objective is controlling a fire's growth, particularly in storage.
Mixing response types within one design area is generally not permitted, because the hydraulic calculation assumes a consistent operating pattern.
Which type is required for which occupancy is set by the standard in force.
Can sprinkler heads be painted or decorated?
Never - a painted head is a head that will not work, and it looks entirely normal.
Paint insulates the thermal element, delaying or preventing operation.
It can also glue the plug into the waterway so the head cannot open even if the element fails.
The same applies to hanging anything from a sprinkler, which can damage the element or the seal.
Where a head must match a ceiling finish, factory-finished heads and concealed heads with matching cover plates are available.
A painted or damaged head is replaced rather than cleaned, and this is one of the most common defects found at inspection.
What obstructs a sprinkler?
Anything between the head and the floor it is meant to protect - and storage is the usual culprit.
Standards specify a minimum clearance below sprinkler heads for exactly this reason.
Stacked goods, new partitions, suspended equipment, ductwork and light fittings all create shadows in the spray pattern.
Changes made long after installation are the common cause, because nobody involved is thinking about the sprinkler design.
A racking layout change can invalidate a system designed for a different storage arrangement entirely.
Obstruction is one of the most frequent findings at sprinkler inspection and one of the easiest to correct.
How are sprinklers matched to what is being protected?
By hazard classification, which drives head type, spacing, density and water supply - and it is a design decision.
Standards classify occupancies by how fast and how intensely a fire is expected to develop.
A light hazard office, an ordinary hazard workshop and a high-piled storage warehouse need very different systems.
Storage introduces its own variables: height, commodity type, packaging and rack configuration all change the answer.
Changing what a building is used for can invalidate a sprinkler design that was correct when installed.
Classifications, densities and design methods differ between markets, so a design from one jurisdiction should not be assumed valid in another.
Can sprinkler heads be reused after they have operated?
No - an operated head is replaced, and heads are never reconditioned or reinstalled.
The thermal element is destroyed by operation, and the seal will not reseat.
Heads that have been exposed to fire conditions without operating are also replaced, since their element may have been degraded.
Spare heads of each type in the system, plus the correct wrench, are normally required to be kept on site.
Replacement heads must match the type, rating, response and finish of the original, which is why the spares stock matters.
Older heads are also subject to periodic sample testing in many regimes, and some types have been the subject of manufacturer recalls.