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CO2 Safety Guide

Find the NFPA 55 compliant detector for your venue — sized in 60 seconds

CO2 Safety Systems for Restaurants, Bars, and Breweries

Answer 4 quick questions — we'll surface the detector kit that matches your venue, code, and sensor count.

Step 1 of 4 ~60 seconds

1. What's your situation?

2. What type of venue is this for?

3. What's your CO2 source size?

4. How many sensor points do you need?

2. What do you currently have?

3. Why are you replacing?

4. How many sensor points will the replacement cover?

Based on your answers:

LogiCO2 MK9 CO2 Safety System Kit — 3 Sensors

Modular multi-sensor controller, scales to 8 sensors. Standard pick for multi-room restaurants and small breweries.

LogiCO2 Mk9 CO2 Safety System Kit – 3 Sensors, Central Unit & Horn/Strobes

NDIR · 0–5% CO2 · 1.5% warn / 3% alarm · 24V DC · Expandable to 8 sensors

 

In stock · Ships same-day
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Anatomy of a CO2 Safety System

What an NFPA 55 compliant install actually looks like

CO2 is heavier than air, so it pools at floor level. Six numbered components — sensor low, alarms high, signage visible — are what an inspector signs off on.

1

Bulk dewar / CO2 tank

The source. Bulk dewar, 20 lb cylinders, or both — NFPA 55 §13.10.1 pulls any indoor beverage CO2 over 100 lb into scope, and most fire marshals require detection on any indoor CO2 regardless of size.

2

CO2 sensor — mounted low

NDIR sensor, 12–18" off the floor on the wall closest to the tank. CO2 is 1.5× heavier than air and pools at floor level — a sensor at eye height alarms too late.

3

Low-voltage signal cable

Runs sensor to central unit through conduit where exposed. ~30 ft max on a standard run; longer needs the manufacturer's extended-cable kit. Exits the protected room through the wall, not the door.

4

LogiCO2 central unit

The controller that reads sensor signals, drives alarms, and logs events. Mounted outside the protected room at eye level so staff see status before they enter.

5

Strobe + horn

Audible/visible alarm mounted high above every entrance to the protected room. A worker approaching the door must see and hear the alarm before opening it. Code-required, not optional.

6

DANGER signage

"CO2 Alarm — Do Not Enter When Flashing" placard adjacent to the strobe, plus central-unit ID sign and emergency-contact info. AHJs check every one of these on inspection.

Side-by-side Specs

CO2 Safety Systems, Compared

The four systems commercial operators most often install through us — specced for the exact compliance and sensor-count questions our tech line hears every week.

Specs
Your match
LogiCO2 Mk9 CO2 Safety System Kit
LogiCO2 MK9 Kit3 sensors + central unit
Your match
LogiCO2 MK90 Stand-Alone CO2 Safety System
LogiCO2 MK90Stand-alone single-sensor
Your match
Analox Ax60+ Commercial CO2 Leak Detector
Analox Ax60+Universal wall-mount
Your match
LogiCO2 Scout Glow Portable CO2 Detector
Scout GlowPortable spot checker
Best for Multi-room restaurants & small breweries Single-room bar walk-in or small kitchen Vendor-neutral spec or non-LogiCO2 site Pre-entry spot checks & walk-arounds
Sensor points 3 (expandable to 8) 1 1 (modular add-ons) 1 (handheld)
Expandable Up to 8 sensors Via add-on kit Modular sensor add-ons No
Sensor type NDIR NDIR NDIR NDIR
Detection range 0–5% CO2 0–5% CO2 0–5% CO2 0–5% CO2
Alarm thresholds 1.5% warn / 3% alarm 1.5% warn / 3% alarm 1.5% warn / 3% alarm Audible + LED at threshold
Built-in horn/strobe Separate horn/strobe included ✓ Built-in External horn/strobe Onboard buzzer + LED
Wired / wireless / portable Wired Wired Wired (PoE or AC) Portable / battery
NFPA 55 compliant ✓ ✓ ✓ — (supplement only)
Made in Sweden Sweden UK Sweden
Stock status In stock In stock In stock In stock
Price — — — —
Shop More info → More info → More info → More info →

Spec sheets, install drawings, NFPA 55 reference card, and a sensor-count worksheet are bundled in the free compliance PDF — or call 888-964-4239 for a custom system spec.

Pre-install Checklist

Before you order: 7 things the install crew will ask you

If you can answer these before the system ships, install drops from half a day to under two hours.

1
Confirm room volume (cubic feet) for every space CO2 piping runs through.

Sensor count is driven by room volume, not floor area. Length × width × ceiling height per room — give us the number for each.

2
Identify every CO2 source on the site.

Bulk tanks, 20 lb cylinders, soda dispensers, and carbonators each count separately for NFPA 55 §13.10.1 totals. Stack them up — the threshold is more than 100 lb installed.

3
Mark each sensor mount location 12–18" off the floor near the CO2 source.

CO2 pools low. Mount on the wall closest to a likely leak point — tank valve, manifold, regulator — not the opposite wall. Avoid dead corners and shelf shadows.

4
Plan strobe + horn placement outside the entry door.

Visible and audible to anyone approaching the room. Eye-level on the outside wall is standard; some AHJs require a second annunciator inside the room.

5
Run 24V DC power to the central unit location.

Non-switched, not shared with the walk-in compressor or any cycling load. Nuisance trips kill the system the day you need it.

6
Plan cable route from sensor to central unit (max 30 ft typical).

Conduit where exposed. Protect from water in coolers and ice rooms. Longer runs need the manufacturer's extended cable kit — confirm before you mount.

7
Order required signage to match your local fire code edition.

"CO2 Alarm — Do Not Enter," central-unit ID, beacon and siren placards. Cheap to order, expensive to skip — inspectors check every one.

CO2 Safety FAQ

Questions we get on the tech line every week

Does my restaurant really need a CO2 detector?
If you have any indoor or below-grade CO2 — bulk tank, cylinders, soda dispenser, or carbonator — odds are yes. NFPA 55 §13.10.1 sets the explicit threshold for beverage CO2 at more than 100 lb installed, but the IFC and most fire marshals require detection in any room where a leak can collect, regardless of cylinder size. A 20 lb tank fully released into a small basement bar is a lethal exposure. Confirm with your local AHJ, but plan on monitoring as the default for any indoor system with staff in a confined space.
What's NFPA 55 and does it apply to me?
NFPA 55 is the model code for compressed gases and cryogenic fluids — the document most authorities having jurisdiction lean on for CO2 storage and use. Chapter 13 governs beverage CO2 specifically. §13.10.4 requires emergency gas detection and alarm for any CO2 storage indoors or anywhere a leak can collect, and §13.6.2 sets the OSHA PEL (5,000 ppm) and STEL (30,000 ppm) as the alarm thresholds. Most states adopt NFPA 55 or the parallel IFC §5307.3, sometimes with amendments. If you serve beer, soda, or carbonated water in a permitted commercial space, it almost certainly applies.
How many sensors do I need?
One sensor per room or below-grade enclosure where CO2 piping runs. A single sensor does not cover two cellars connected by a doorway, a walk-in plus a bulk room, or a kitchen plus a basement. Most multi-room restaurants and small breweries land on 2–3 sensors. Bulk-storage rooms, mezzanines, and stairwells where CO2 can settle each need their own. Send us a room-by-room cubic-footage list and we'll mark up the count.
Where should the sensor be mounted?
12–18" off the floor, on the wall closest to where a leak is most likely — typically near the tank valve, manifold, or distribution piping, not the opposite wall. CO2 is 1.5× heavier than air and pools at floor level. A sensor at eye height over a doorway is decorative — it will alarm too late. Avoid dead-air corners, behind shelving, or directly above floor drains where airflow patterns can mask a leak. Both the IFC and the NBIC explicitly call out the 12-inch height in the area where gas is most likely to accumulate.
How do I function test the system annually?
Use the manufacturer's function-test gas injection tool to drive the sensor reading past each alarm threshold. Confirm the warning alarm triggers at the low set point (1.5% / 15,000 ppm), the high alarm triggers at the high set point (3% / 30,000 ppm), the horn and strobe activate, and any tied solenoid valve closes. Log the test date, sensor ID, technician, and result. Run a function test at commissioning, after any service, and at least annually. Most AHJs and insurance carriers want the log on file.
What if my CO2 tank is outside?
Not necessarily exempt. NFPA 55 and the IFC both call out below-grade outdoor locations as needing gas detection because CO2 pools in pits, areaways, and stairwells. If your indoor distribution lines run through an enclosed cellar, the cellar still needs monitoring. The tank being outside reduces but does not eliminate the leak risk inside the building.
Does my fire marshal really check?
Yes, increasingly so since 2016. Inspectors are looking for sensor placement (within 12 inches of the floor), correct alarm thresholds (5,000 ppm warning, 30,000 ppm high), audible-visible alarms at the entrance, signage, and documented annual function tests. Failure to comply has produced citations, occupancy holds, and in some jurisdictions refusal to issue or renew permits. The compliance cost is small; the cost of failing inspection mid-build is not.
How much does compliance cost end-to-end?
A single-sensor stand-alone (MK90) for a typical bar walk-in lands in the low four figures all-in with signage, install, and the function-test tool. Multi-sensor MK9 builds for restaurants, breweries, and grocery stores scale from there based on sensor count and central-unit placement. Ongoing cost is limited to annual function testing and sensor replacement on the manufacturer's published schedule (typically 5 years). Email us your floor plan and we'll send a fully specced bill of materials with install labor estimate.
CO2 Compliance Guide

Get the free CO2 compliance guide

8-page PDF. NFPA 55 walkthrough, sensor placement, install checklist, and the cheapest compliant kit per occupancy class. Sent to your inbox instantly.

No spam. Unsubscribe any time. Compliance updates only when codes change.

Still not sure? Talk to our tech line.

Talk to a real tech, not a chatbot. Mon–Fri 9am–4:30pm CT. Tell us your venue type, room volumes, and CO2 sources and we'll spec the full bill of materials back to you — sensors, central unit, alarms, signage, and the function-test gas tool. Usually within one business day.

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