Inert gas fire extinguishing

Inert gas fire-extinguishing systems use colourless, non-corrosive gases normally found in the atmosphere: ARGON and NITROGEN.

They are considered clean agent systems because their use ensures quick and clean extinguishing, without releasing any residue into the area where the agent is dispensed and allowing rapid resumption of activities after use.

The easy availability of components, the absence of environmental impact, the lack of constraints on actual discharge tests of the systems, and the low maintenance and recharging costs make inert gas systems a good choice for protecting even sites where delicate and valuable objects are kept.

Correct design of the system makes it possible to safely distribute the gas evenly in the environment, without causing harm to people or damage to objects in the room.

Inert gas automatic fire-extinguishing systems are triggered when the fire detection system sends an alarm signal to the control unit, which takes the action for which it has been programmed, extinguishing the fire in a very short time.

In order to ensure their effectiveness, it is essential that the checks required by the standards, which detail all the activities and maintenance schedules, be performed by specialised personnel.

Maintenance phases and frequency

Documentation to be acquired prior to starting maintenance activities

• User and maintenance manual;
• As-built designs and documentation of the system;
• Manufacturers' test procedure;
• Test equipment;
• Electronic instruments suitable for the tests to be performed.

Initial inspection

To be performed by the Maintenance Technician

Preliminary Inspection

• Verification that the system corresponds to the executive plan; Installation in conformity with the standard;
• Visual inspection of the system;
• Checking the cylinders and related calculations.

Functional Check

• Verification that the system logics correspond to the project requirements and the operating documents as well as the user and maintenance manual;
• In the presence of other interconnected systems (active or passive protection or technological systems), check that the system logics are consistent with the project requirements.

Monitoring

To be completed by the Assigned personnel

What?

• Visual inspection;
• Checking the condition of cylinders, nozzles, goosenecks, etc., at least monthly.

When?

• Daily, weekly, monthly depending on the type of check to be carried out and the size of the system.

Increase frequency in the case of:

• Installations in environments with a high density of personnel;
• Installations in environments with frequent temperature changes;
• Installations in environments with high humidity or presence of vapours;
• Specific requirements of the manufacturer or designer.

Periodic inspection

To be performed by the Maintenance Technician

What?

• Check that the initial inspection documents are on hand;
• Check that no actions have been taken or structural changes made in the protected environment;
• Verification of the state of the system.

How?

Conventional systems:

-

100% testing of devices

Analogue Systems:

0-6 years

Over a period of 12 months a functional check must be performed on 50% of all devices in all detection zones (twice per year)

7-12 years

Over a period of 12 months a functional check must be performed on 100% of all devices (twice per year)

beyond 12 years

After 12 years the system must undergo a general review

General system check

To be performed by the Maintenance Technician

When?

• At least once every 12 years.

What?

• Verification of the availability of spare parts;
• Verification that the system has not changed (if substantial modifications have been made, the technical documentation must be acquired in the new as-built configuration).

How?

• Factory overhaul;
• Replacement with new detectors;
• Execution of physical test.