Between Fire Suppression Service Visits: What a Kitchen Supervisor Can Check Without Touching Anything

Pictured above: electrostatic filter cells lifted out of a hood during a clean on one of our projects (Sushi Go, VivoCity). It is not a suppression job. It is reused here because a hood opened up for cleaning is the one moment the nozzles and links above the cooking line are in easy reach, and that is the moment most kitchens never use.

A kitchen hood suppression system is serviced on a schedule by a technician. Between those visits it sits above the cooking line for months, in the greasiest air in the building, and nobody on the kitchen team is asked to look at it. Then a menu changes, a fryer gets moved, a crate gets stacked in the wrong corner, and by the time the technician returns, the system on the wall no longer matches the kitchen underneath it.

This post is for the supervisor or owner who wants a short, safe routine for the gaps between visits. It is not a replacement for the service, and it does not ask anyone to touch the agent, the detection or the cylinder. It is about looking: five minutes, no tools, nothing opened, and a note of what you saw. It does not give a price, because servicing is quoted after an inspection of the actual system.

The short answer

You cannot service a suppression system yourself, but you can notice when something has changed around it. Look at the manual pull station, the nozzle caps, the cooking line against the nozzles, the grease on and around the nozzles and links, the gauge, and the signage. Write down what you saw and the date. Anything that looks different from last time goes to whoever services the system, not to the next shift.

Why the gaps between visits are where it goes wrong

A suppression system fails quietly. Nozzles clog with grease. Fusible links foul. Cylinder pressure drifts. Detection drifts out of position. None of that is visible from the floor on the day it matters, which is why the service visit exists. But a lot of what goes wrong between visits is not inside the system at all. It is the kitchen changing around it.

The grease is the link to everything else in the hood. The same build-up we remove during an exhaust clean also fouls the nozzles and coats the fusible links, and a link that is greased over can fail to release at the temperature it was rated for. A system is not a box on the wall that stays clean on its own. It lives in the dirtiest part of the kitchen.

The five-minute walk-round

Do it with the line cold and the fan off, at the end of the night or before the prep shift. Stand where you can see the hood and the line together.

1. The manual pull station: can you reach it, and can everyone? The manual pull station is there so staff can trigger the system by hand if they see a fire first. Look at where it is, and whether anything is stacked, hung or parked in front of it tonight. Look at the signage too: if it is missing, faded or covered, a new hire will not know where to go. Ask one new member of the team to point to it without being told.
2. The nozzle caps: are they all there? Nozzles carry blow-off caps that keep grease out of the opening. A nozzle without its cap clogs with grease and may not discharge properly. You are not removing anything. You are looking up at each nozzle over the line and noting any that has no cap, or a cap that looks damaged or caked.
3. The line against the nozzles: is every appliance still under one? A suppression system is built around the cooking line, with nozzles aimed at specific appliances in specific positions. Stand at the hood and ask: is every appliance that is cooking today still where the system was designed to cover it? Has a fryer been swapped for a bigger one, a griddle moved a hand's width, a new appliance squeezed in at the end? If yes, say so to your suppression servicer before the next visit, not at it. Our post on adding cooking equipment to an existing hood explains why a move that looks small can leave an appliance outside the coverage.
4. Grease on and around the nozzles and links. Do not wipe, scrape or spray anything near them. Just look. If the nozzles over the line are caked in grease, or the links above them look coated in cooking residue, the hood is overdue for a clean and the suppression components are being fouled along with it. Photograph what you see with your phone. A fusible link is a heat-sensitive trigger: it is not a thing for the kitchen team to touch, clean or replace.
5. The gauge: write down what it reads. The service visit checks the pressure gauge and the condition of the cylinder, so there is charge behind the nozzles. You are not judging whether the reading is right. You are writing it down with the date, so that if it ever looks different from last month, someone notices. A reading on paper is a baseline; "it looks about the same" is an opinion.

Add the date of the last exhaust clean to the note. Our published guidance is a clean every one to three months for most commercial kitchens, monthly for heavy wok, grill and deep-frying kitchens and quarterly for lighter ones. The longer the hood goes between cleans, the more grease reaches the nozzles and links.

What the kitchen team can do, and what it must leave alone

Some basic checks, such as making sure the nozzle caps are in place and the filters are clean, are within reach of a trained kitchen supervisor. That is the list above. Anything involving the agent, the detection circuit, the fusible links or the cylinder belongs to a specialist.

• Do: look, photograph, write down, keep the pull station clear, and tell the servicer when the line changes.
• Do not: wipe or spray the nozzles, bend or knock a link, tape over a nozzle to keep grease off, hang cloths or utensils from the pipework, or reset or test anything. A tampered system is worse than a dirty one, because it looks fine.
• Do not run a full line under a hood with a missing nozzle cap or a blocked pull station and call it a note for later.

What should be on paper, and where it should live

Every service visit is documented, so you have a dated record of upkeep to show SCDF, your landlord, your insurer or an auditor. Your walk-round note is the other half: it shows what the kitchen did in the months between visits. Keep both in the same folder as your exhaust cleaning records. A documented service history, kept alongside your cleaning records, covers the full fire-safety picture SCDF expects of a commercial kitchen.

A simple note is enough: date, who looked, pull station clear (yes or no), caps present (yes or no), any appliance moved since the last visit, grease visible on nozzles or links (yes or no), gauge reading, a photo. Five lines on one page, kept by the kitchen supervisor.

When to ring the servicer between visits

• A nozzle cap is missing, damaged or caked in grease.
• An appliance has been added, swapped or moved since the last visit.
• The pull station is blocked, damaged, or someone cannot say where it is.
• The gauge reading looks different from your last note.
• There has been a flare-up under the hood, even a small one that staff put out themselves, because the detection links above the flare may have been exposed to heat.
• The hood is well overdue a clean and the nozzles and links are visibly coated.

If the system has discharged, that is a different procedure. What to do when a restaurant fire suppression system goes off is set out in a separate post.

Questions to ask at the next service visit

1. Is every nozzle still aimed at an appliance that is actually under the hood today?
2. What did the gauge read, and is the reading written down?
3. Were the fusible links replaced, and when are they next due?
4. Was the gas and electrical shut-off interlock verified, so a discharge cuts fuel and power to the cooking line?
5. What was replaced, and what was left as it was?
6. Does the report match what you can see over the line? If the report says everything is fine and the nozzles are caked in grease, ask again.

What a service visit should leave you with is covered in a separate post, along with the questions worth putting to any servicer.

Why suppression and exhaust cleaning belong on one visit

Grease is the enemy of both systems. Servicing the suppression and cleaning the exhaust on one coordinated visit means one team sees the whole cooking line: the nozzles and links get looked at while the hood is open, and neither job gets skipped. We service suppression systems whoever installed them. If you have inherited a system with an unknown service history, we inspect it, tell you honestly what condition it is in, and set up a schedule from there.

The full list of what a visit covers is on our fire suppression maintenance page, and the system itself, how it works and what it protects, is on fire suppression systems.

What to send us

If your walk-round finds something, or you are not sure what you are looking at, WhatsApp BC Air on 8989 2833 with a photo of the pull station and the nozzles over the line, what you cook, the date of the last service and the date of the last clean. We are on 24/7 standby. We give no price in a post: every kitchen is different, and the quotation follows an inspection of the actual system.

The short version

• Between service visits, the kitchen cannot service the system, but it can notice when something has changed around it.
• Five minutes, line cold, nothing touched: pull station clear, caps present, every appliance still under a nozzle, no visible grease build-up on nozzles and links, gauge reading written down.
• Agent, detection, fusible links and cylinder are for the specialist. Wiping, taping or hanging things on the pipework makes it worse.
• Any change on the line, or any flare-up, goes to the servicer the same day.
• Keep the walk-round note with the service reports and the cleaning records.

Related reading: what a suppression service visit should leave you with · when the suppression system has gone off · adding cooking equipment to an existing hood · hood, fan, gas and suppression interlocks