Why you should inspect your fire sprinkler heads in exhaust ducts!

Fire sprinkler heads in kitchen hoods and exhaust ducts are required to be inspected every year for an excessive accumulation of grease or any other foreign matter. Checking these fire sprinkler heads is a task that is not regularly completed by inspectors let alone even knowing where these sprinkler heads are located in a building. In this article we will explain what are the requirements and how to identify sprinkler heads that need to be replaced.
Russ Porteous
CEO, Firewize
17 Feb, 2021
Sprinkler Head Contaminated in Duct

Buildings fitted with a required automatic fire sprinkler system designed to Australian Standard AS 2118.1 that include a commercial kitchen will also incorporate cooking equipment, kitchen hoods and associated ventilation systems (including exhaust ducts).

Unfortunately over time kitchen hoods and exhaust ducts accumulate oil, grease and other byproducts of cooking in kitchens.  This accumulation can lead to a fire and promote the spread of fire.

An automatic fire sprinkler system is installed in kitchen hoods and ducts to protect these locations from a fire or help prevent the spread of fire through a building.

These systems are designed to Australian Standard AS 2118.1. The Standard requires sprinkler heads to be installed at specific locations;

  1. under kitchen hoods, not more than 3.6 meters apart; and
  2. in horizontal ducts 4 meters apart;1 or
  3. at the head of a vertical rising duct.

Where the cooking equipment includes a deep fat fryer, there are other considerations that installers and maintainers MUST take into consideration.

Inspection & Maintenance Requirements

The inspection and maintenance requirements for automatic fire sprinkler heads in ducts is set out in Australian Standard AS 1851 in Table 2.4.2.3 as described below;

Item No. Item Action required and pass/fail requirement
3.14 Kitchen hoods and ducts INSPECT all sprinklers inside kitchen hoods and ducts and CLEAN if necessary to remove accumulated grease and any other foreign matter and verify that the sprinkler head is appropriate for this application.
3 Contaminated Fire Sprinkler Heads in Exhaust Duct

Where automatic fire sprinkler heads are installed to protect the kitchen hood or exhaust duct, building owners should ensure contractors are competent to conduct an inspection and that the person undertaking the yearly survey of the automatic fire sprinkler system are included in the yearly survey scope of work.

Ideally this item, including the number of fire sprinkler heads to be inspected should be included in any contract scope and terms.

There are an array of defects that may be observed by inspectors including;

  • excessive accumulation of contaminants such as grease;
  • physical damage to the frangible element or deflector;
  • incorrect sprinkler head response time index;
  • missing or damaged mechanical protection;
  • no access for inspection.

If you are responsible for a commercial kitchen with fire sprinkler heads fitted and you observe any of the defects and excessive accumulation of grease or debris around your fire sprinkler heads, then ask us for a free quotation.