Insulated gloves holding a block of dry ice

Services · CO₂ Sensors

CO₂ Sensor Installation & Monitoring

Dry ice turns into carbon dioxide gas that you can't see. PA Dry Ice installs CO₂ sensors for facilities and vehicles that store, handle, ship or use dry ice.

Request a Sensor Consultation How monitoring works

of CO₂ gas from 1 lb of dry ice as it sublimates (approx., at room temperature): ≈8.8 ft³; of CO₂ gas from 1 lb of dry ice as it sublimates (approx., at room temperature)
heavier than air, so CO₂ tends to collect near the floor: ≈1.5×; heavier than air, so CO₂ tends to collect near the floor
OSHA permissible exposure limit for CO₂ (0.5%), 8-hour time-weighted average: 5,000 ppm; OSHA permissible exposure limit for CO₂ (0.5%), 8-hour time-weighted average
oxygen level below which OSHA considers air oxygen-deficient: 19.5%; oxygen level below which OSHA considers air oxygen-deficient

The hazard

Why CO₂ Build-Up Is Dangerous

Cold chain shipping boxes packed with dry ice

CO₂ at high concentrations can cause headaches, dizziness, loss of consciousness and asphyxiation. Around dry ice, three things make it easy to miss:

It never stops sublimating

Stored dry ice turns into CO₂ gas around the clock — overnight, in transit and in closed rooms.

It sinks and collects

CO₂ settles in low areas: floors, pits, basements, cargo beds and the bottom of walk-in freezers.

You can't see the risk

Fog from dry ice is condensed moisture, not CO₂. The gas itself is colorless and practically odorless.

Where monitoring matters most

Walk-in freezers and cold rooms holding dry ice
Delivery vans and truck cargo areas
Packing bays where dry ice is weighed and boxed
Basements, pits and other low or enclosed spaces
Labs with open dry ice baths or storage bins
Tanks, molds and rooms used for dry ice blasting

How it works

Fixed Sensors, Portable Monitors, Alerts & Ventilation

Most programs combine continuous room monitoring with portable devices for people on the move.

Fixed sensors

Mounted in the room for continuous monitoring, typically low where CO₂ collects and near where people work.

Portable monitors

Worn or carried for vehicles, confined spaces, spot checks and anyone moving between areas.

Alerts

Depending on the equipment, audible and visual alarms can warn people before they enter or stay in a space with rising CO₂.

Ventilation

Where the system design allows, a fixed sensor can signal exhaust fans or ventilation to clear the air.

CO₂ vs. oxygen monitors

Why an Oxygen Monitor Isn't Enough

Oxygen monitors alarm when oxygen falls below 19.5%. Displacing enough air to reach that point takes roughly 6–7% CO₂, which is far above CO₂ exposure limits.

Dedicated CO₂ sensor

Measures carbon dioxide directly
Responds at levels relevant to CO₂ exposure limits (ppm)
Gives early warning around dry ice storage and handling

Oxygen-deficiency monitor only

Measures oxygen, not CO₂
Alarms only after a large amount of air is displaced
CO₂ can already be at hazardous levels before it alarms

Many facilities use both. Your safety professional can confirm what your space needs.

Not sure what your space needs? Start with a consultation.

Request a Sensor Consultation

Installation

How Installation Works

A typical installation follows these steps. The equipment, scope and which steps PA Dry Ice performs for your site are confirmed with you during the consultation.

Step 1
Site assessment
Review rooms, dry ice quantities, airflow and how people use the space.
Step 2
Sensor placement
Choose locations and mounting heights for where CO₂ is likely to collect.
Step 3
Configuration
Set alarm points based on your facility's requirements; connect alerts or ventilation where the system supports it.
Step 4
Testing
Check that sensors read and alarms trigger as intended at installation.
Step 5
Maintenance
Follow the calibration and testing schedule the sensor manufacturer specifies; ongoing service options are discussed with your quote.

Industries served

Where Dry Ice Calls for CO₂ Detection

These are the most common places dry ice creates a CO₂ risk. Expand each one to see practical examples.

Using dry ice for blasting? See Why Choose Dry Ice Blasting?

Cold Chain Logistics & Last-Mile DeliveryVehicles and freight areas carrying dry-ice-packed shipments.

Truck cargo areas and delivery vans, where sensors can alert drivers to gas build-up before they open doors or enter.
Airport cargo holding rooms and freight hubs handling dry-ice-packed vaccines and biologicals.

Pharmaceuticals, Medical Labs & Life SciencesUltra-cold storage and lab sample handling.

Biobanks, hospitals and pharmaceutical distribution centers storing samples in walk-in freezers with dry ice; low-mounted sensors can be tied to exhaust ventilation.
Enclosed labs with open dry ice baths or bins, where personal or fixed monitors help keep exposure below OSHA limits.

Dry Ice Manufacturing & StorageProduction, storage silos and packing areas.

Pellet and block production, where converting liquid CO₂ to dry ice releases significant gas; ambient sensors protect plant workers.
Bulk storage and packing areas that sublimate constantly, often with floor-level monitors wired to ventilation.

Dry Ice BlastingIndoor and confined-space cleaning with dry ice pellets.

Automotive, manufacturing and power facilities where pellets are blasted indoors.
Blasting inside tanks, molds or enclosed rooms, where portable CO₂ monitoring is essential and typically part of a confined-space program.

Food & Beverage Processing / CateringKitchens and fulfillment bays packing with dry ice.

Airline catering and event kitchens packing large numbers of meal boxes on open assembly lines.
Frozen meat, seafood and ice cream fulfillment bays where dry ice is weighed and boxed by hand.

Planning

What Affects Installation Requirements & Pricing

Number of rooms, vehicles or zones to monitor
Size, layout and airflow of each space
How much dry ice or CO₂ is stored or used
Fixed sensors, portable monitors, or both
Connecting alarms or ventilation
Mounting, wiring and power at each location
Your safety program, insurer and local code requirements

Pricing is quoted after we understand your space; we don't publish standard pricing. This page is general information, not a safety assessment — monitoring requirements vary by facility, application and jurisdiction.

FAQs

CO₂ Sensor Questions

Where should CO₂ sensors be placed?

Because CO₂ is heavier than air, sensors are generally mounted low, near where gas collects and where people work or enter. Exact locations and heights depend on the room, airflow and how dry ice is stored, and are confirmed during the site assessment.

What happens when an alarm goes off?

Alarms are meant to warn people to leave or stay out of the space and to ventilate it before re-entry. Your facility should have a written response procedure. Alarm points are configured to your facility's requirements and applicable exposure limits.

Can I just use an oxygen monitor?

Not on its own. CO₂ reaches hazardous levels well before oxygen drops to the 19.5% level that triggers a standard oxygen-deficiency alarm. A dedicated CO₂ sensor measures the gas that is actually building up.

How often do sensors need inspection or calibration?

It depends on the sensor. Follow the manufacturer's calibration and testing schedule; we'll cover maintenance considerations for the equipment recommended for your site.

Is CO₂ monitoring required for my facility?

Requirements depend on your facility, how much dry ice or CO₂ you handle, local codes and your insurer. Many facilities that store or handle dry ice in enclosed spaces choose continuous monitoring. Confirm specific obligations with your safety professional or the authority having jurisdiction.

Is my facility a good candidate?

If dry ice is stored, packed or used in a closed room, cold storage unit, vehicle or low area, monitoring is worth discussing. Tell us about your space and we'll talk through options.

Talk to us about CO₂ monitoring

Tell us your facility type, location and what you need to monitor — the PA Dry Ice team will follow up.