MH series Nafion® gas humidifiers for precision applications
Active membrane humidification with superior accuracy and stability
The Perma Pure MH series delivers reproducible gas humidification up to 98% RH for calibration, sensor development and OEM measuring systems. Based on patented Nafion™ membrane technology with an active water source.
Key advantages for OEM applications
- Accurate humidity control: stable RH values within milliseconds, reproducible over a wide flow range (up to 20 L/min)
- No contamination: zero aerosols, no condensation, gas composition remains fully intact
- Maintenance-free design: no moving parts, corrosion-resistant, long service life
- Fast response time: first-order kinetics for an immediate response to flow and temperature changes
- Widely applicable: suitable for analytical instruments, laboratory setups and industrial calibration
Operating principle: selective water permeation through a Nafion™ membrane
The MH series works on the tube-in-shell principle with active water-to-gas humidification:
Process step by step:
- Dry process gas flows through the Nafion™ tubing (tube side)
- Deionised water is supplied on the shell side
- Water is absorbed into the molecular structure of the Nafion™ membrane
- Water vapour diffuses selectively into the gas stream
- The humidified gas stream leaves the unit at the set RH value
Waarom Nafion™ superieur is:
- Only water vapour passes through the membrane: no liquid carry-over
- No loss of analytes or gas components
- No droplet formation or atomisation
- Chemically inert and resistant to aggressive environments
First-order kinetics: fast and stable humidity control
Moisture exchange in the MH series follows a first-order kinetic reaction, which ensures:
- Direct response: humidification rate proportional to the difference in water activity
- Millisecond equilibrium: moisture equilibrium is reached virtually immediately
- Stable output: reproducible RH values, even at variable flows
- Predictable performance: ideal for analytical and calibration applications
These kinetics make the MH series ideally suited for applications where precision and reproducibility are critical, such as sensor calibration, leak detection equipment and analytical measuring instruments.
Technical specifications and performance
Performance curves MH-070
Test conditions:
- Water supply: 5 inch water column static pressure (no flow)
- Water temperature: controlled as indicated on the curve
- Housing: insulated
- Process gas: air at atmospheric pressure, 24°C, dew point < -40°C
- Measuring method: EG&G chilled mirror dew point meter
Note: for consistent performance, the humidifier must be kept at a constant temperature, or the water must be circulated with temperature control. Evaporation is an endothermic process that extracts heat.
Product specifications
Technical features
- Humidification range: up to 98% RH
- Flow capacity: up to 20 L/min (depending on model)
- Humidity control: via water temperature or gas flow
- Response time: milliseconds (first-order kinetics)
- Pressure drop: low, depending on model (MH-110 has the lowest ΔP)
- Water type: deionised water required
- Materials: corrosion-resistant construction
- Maintenance: no moving parts, low-maintenance
Important design considerations
- Temperature control is essential: insulate the unit or use a temperature-controlled water circulation system
- Water-to-gas mode: for gas-to-gas humidification, the FC or MD series are more suitable
- Sterile applications: suitable for cleanroom and sensitive analytical environments
Fields of application
The MH series is widely used in:
- Calibration laboratories: reference RH generation for sensor validation
- OEM-meetinstrumenten: Geïntegreerde bevochtiging in analytische systemen
- Sensor development: R&D for humidity-dependent sensors
- Leak detection equipment: stable RH for carrier gas conditioning
- Respiratory/medical analysis: contamination-free gas humidification
- Industrial process monitoring: reproducible test conditions
Ordering matrix and configuration options
Dimensions and installation
Why choose the MH series?
Technical superiority
- Patented Nafion™ technology with a proven track record
- First-order kinetics for the fastest response time in the industry
- No competing technology combines accuracy with reliability
OEM-friendly
- Compact dimensions for easy integration
- Maintenance-free design lowers total cost of ownership
- Long service life ensures product field reliability
Proven in practice
- Widely installed base in laboratories
- Local technical support available
- Meets European quality and safety standards
Request product information right away
Want to integrate the MH series into your OEM system or laboratory setup?
Our application engineers are happy to advise you on:
- Model selection based on your specifications (flow, RH range, pressure drop)
- System integration and temperature control - customisation options for OEM applications
- Lead times and technical documentation
Contact us for:
- Detailed technical datasheets
- Application-specific performance curves
- A tailored quotation for your project
- Samples for evaluation (if available)
