Need help choosing the right monitor?
Talk to a SpecialistProtect Personnel from Oxygen Deficiency
with continuous, low-maintenance monitoring
The AMI Model 221R continuously monitors for both oxygen-deficient and oxygen-enriched conditions, helping protect personnel in industrial and laboratory environments. Designed for industrial and laboratory applications, the 221R combines long-life zirconium oxide sensor technology with reliable performance to reduce maintenance while helping facilities meet OSHA oxygen monitoring requirements.
Long sensor life reduces maintenance and replacement costs.
Independently tested for reliable operation.
Real-time oxygen monitoring with visual and audible alarms.
No frequent sensor replacement associated with electrochemical technology.
Flexible sensor placement for application-specific monitoring.
Supports oxygen deficiency and oxygen enrichment monitoring requirements in industrial environments.
Trusted Where Oxygen
Deficiency Risks Exist
Applications Across Critical Industries
Where nitrogen, argon, helium, carbon dioxide, or other inert gases are used, oxygen levels can become dangerously low without warning. The Model 221R provides continuous oxygen deficiency monitoring to help protect personnel and maintain safer operations.
Have questions about the right oxygen monitoring solution?
Talk to a SpecialistWhy Facilities Choose the 221R
Reliable, Long-Lasting, OSHA Compliant Protection
Lower Maintenance Costs
The 10-year zirconium oxide sensor dramatically reduces routine maintenance and minimizes downtime compared to traditional electrochemical sensors.
Stable, Reliable Readings
Zirconium oxide technology provides excellent long-term stability with minimal sensor drift, reducing nuisance alarms and improving confidence in oxygen measurements.
Backup Battery Protection
Built-in battery backup helps keep the monitor operating during power interruptions, providing continued oxygen monitoring when it’s needed most.
Watch Video >Audible and Visual Alarms
Continuously monitors for oxygen-deficient and oxygen-enriched conditions, with audible and visual alarms when unsafe levels are detected.
Built for Industrial Environments
Designed for demanding industrial and laboratory applications where reliability is essential.
Washdown-Ready
Engineered for facilities that must perform washdowns for sanitary compliance. Sensor and electronics are protected from indirect water spray.
Easy Installation & 2-Year Warranty
Flexible installation options plus a 2-year warranty covering parts, labor, and zirconium oxide sensors.
Watch Video >OSHA Compliant Protection
Helps facilities meet OSHA oxygen safety requirements by continuously monitoring for oxygen levels below 19.5%.
Why Zirconium Oxide?
The Advantage of Zirconium Oxide Sensor Technology
Many oxygen deficiency monitors rely on electrochemical sensors that require frequent replacement. The Model 221R uses zirconium oxide technology to provide:
- Longer sensor life
- Lower maintenance requirements
- Excellent long-term stability
- Reduced calibration frequency
- Lower total cost of ownership
- Reliable operation in demanding environments
Competitive Comparison
How the 221R Compares
| Feature | AMI 221R | Typical Electrochemical Monitor |
|---|---|---|
| Sensor Life | Up to 10 Years | 1-3 Years |
| Maintenance | Low | Frequent |
| Sensor Drift | Very Low | Higher |
| Long-Term Stability | Excellent | Moderate |
| Total Ownership Cost | Lower | Higher |
| Industrial Reliability | Excellent | Good |
Installation & Maintenance
Designed for Easy Ownership
The Model 221R is designed to minimize ongoing maintenance while providing dependable monitoring throughout its service life.
Highlights- Simple 3-step installation process
- 10-year life zirconium oxide sensor
- Annual calibration required
- Simple air calibration procedure
- Washdown-ready enclosure
- 2 year warranty covering parts, labor, and the zirconium oxide sensor
Easy 3-Step Installation
Frequently Asked Questions
How much does the Model 221R cost?
The Model 221R starts at $2,033. Pricing may vary depending on configuration and accessories.
How quickly does the Model 221R ship?
Contact AMI for current lead times. The 221R is built to help facilities get critical oxygen monitoring in place quickly.
When should I use the remote probe option?
The remote probe allows the sensor to be placed separately from the monitor, making it ideal for hard-to-reach or remote monitoring locations. The probe can be located up to 300 feet from the control unit.
What outputs and relays does the 221R provide?
The 221R includes a 4-20 mA output and alarm relays for integration with external equipment such as ventilation systems, beacons, and other safety devices.
How often does the 221R require calibration?
The long-life zirconium oxide sensor is designed for excellent stability and low maintenance. Periodic calibration is recommended to ensure accurate performance.
Where should the Model 221R be installed?
The 221R should be installed in areas where inert gases could displace oxygen, including laboratories, cryogenic storage areas, MRI rooms, gas production facilities, and other enclosed or poorly ventilated spaces.
What is covered by the 2-year warranty?
The Model 221R includes a 2-year warranty covering parts, labor, and the zirconium oxide sensor against defects in materials or workmanship. The sensor's up to 10-year expected life refers to its service life and is separate from the warranty period.
Why choose zirconium oxide instead of electrochemical sensors?
Zirconium oxide sensors offer significantly longer service life, excellent stability, and lower maintenance requirements, reducing long-term operating costs.
Is the 221R OSHA compliant?
The 221R is designed to support facilities in meeting OSHA oxygen deficiency monitoring requirements. Proper installation and maintenance should follow applicable regulations and site-specific safety procedures.
What maintenance is required?
Routine inspections, periodic calibration verification, and general system maintenance help ensure reliable long-term operation.
Trusted by Safety Professionals
6000+
Units Shipped
USA
Assembled in the USA
UL
Certified
Protect Your Facility with Reliable Oxygen Deficiency Monitoring
Whether you’re designing a new facility or upgrading an existing safety system, our engineers can help you select the right oxygen monitoring solution.
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