Significant quantities of carbon dioxide are generated during fermentation. Escaping CO₂ in enclosed production areas can collect in low-lying zones and displace oxygen, presenting an invisible hazard to personnel. The source CETCI application note recommends simultaneous continuous monitoring of CO₂ and O₂ for winery fermentation rooms.
Two parameters indicate different facets of the same risk: elevated CO₂ and declining O₂.
Why Does CO₂ Accumulate in Wine Fermentation?
The reference document lists pits, sump areas, storage tanks, and bottling lines—alongside fermentation rooms—as areas warranting attention for elevated CO₂ levels. Because CO₂ is denser than air, it can form “gas pockets” in low-lying areas.
Why Are CO₂ and O₂ Monitored Together?
CO₂ accumulation can displace oxygen, causing O₂ levels to drop. For this reason, the reference system deploys the LPT-A-O₂ electrochemical oxygen transmitter alongside the AST-IS18 NDIR CO₂ transmitter. This renders both gas accumulation and oxygen deficiency visible.
Measuring Ranges in the Reference System
According to the document, the LPT-A-O₂ measuring range is 0–25% vol O₂, whilst the AST-IS18 CO₂ measuring range is specified as 0–4% vol CO₂ . These represent model configurations in the reference document; current product selection must be verified independently.
Sensor Mounting Height
It is recommended to install the oxygen transmitter at breathing zone height, approximately 4–6 ft level and in close proximity to fermentation tanks. In the source example, the CO₂ transmitter is positioned nearby to monitor the same zone. On site, the heavy-gas behaviour of CO₂ and pit/low-elevation areas must be evaluated separately.
QCC Alarm and Ventilation Logic
The QCC is positioned outside the entrance. If O₂ drops below a safe threshold or a CO₂ alarm is triggered, beacons/sounders can be activated; mechanical ventilation or other safety procedures can be initiated via relays. A QCC-RDM remote display is recommended for secondary entrances.
High-Risk Areas in Wineries
| Area | Potential risk | Measurement approach |
|---|---|---|
| Fermentation room | High CO₂ + O₂ depletion | Continuous CO₂/O₂ monitoring |
| Pit / sump | CO₂ accumulation | Low-elevation risk analysis |
| Tank perimeter | Fermentation gas | Close-proximity area monitoring |
| Bottling area | Process CO₂ may be present | Process-based CO₂/O₂ evaluation |
| Room entrance | Viewing atmospheric conditions beforehand | External controller/remote display |
Which CO2 and Oxygen Detectors Should Be Selected for Wineries?
In fermentation areas, an appropriate infrared sensor for CO₂, an electrochemical O₂ sensor for oxygen, and centralised display outside the entrance should be evaluated in unison. NOVEL reviews measuring range, washdown conditions, alarm levels, and mechanical ventilation integration on a project-by-project basis when specifying fixed gas detectors and control systems. View Fixed Gas Detectors.
Let Us Select the Right Gas Detector for Your Application Together
Share your target gas, expected concentration, area layout, and automation requirements. The NOVEL Technical Team will conduct a technical assessment for sensor type, installation location, and system architecture.
Frequently Asked Questions
Why is a CO2 detector required in a winery?
Substantial quantities of CO₂ can be generated during fermentation and accumulate in enclosed spaces.
Is a CO2 sensor sufficient on its own?
The reference application recommends monitoring O₂ levels alongside CO₂, as CO₂ accumulation can displace oxygen.
In what range does the oxygen sensor measure?
A measuring range of 0–25% vol is specified in the reference LPT-A-O₂ configuration.
What technology is used in the CO2 sensor?
The source states that the AST-IS18 transmitter utilises an NDIR (non-dispersive infrared) CO₂ sensor.
Can ventilation be operated in the event of an alarm?
Yes. The reference QCC relays can be utilised to trigger mechanical ventilation and remote alarm signalling devices.
Is it possible to view gas levels before entering the room?
By positioning the QCC or QCC-RDM outside the entrance, internal ambient levels can be verified prior to entry.
Reference and Technical Note
The application architecture and model-specific technical details in this article have been compiled from an application document provided by Critical Environment Technologies Canada Inc. . As source materials may be superseded, current product codes, certificates, measuring ranges, and local regulations must be independently verified prior to project design or procurement.
Author: NOVEL Technical Team
Publication date: 7 September 2026