POLi MP400P – Confined Space Entry Monitors


The POLI multi-gas detectors (MP400/MP400P/MP400S/MP400H) offer 4- or 5-gas monitoring of oxygen (O2), combustibles (LEL), numerous toxic gas options, carbon dioxide (CO2), and volatile organic compounds (VOCs). The MP400 is a basic 4-gas model with diffusion sampling, often configured with O2, LEL, carbon monoxide (CO) and Hydrogen Sulfide (H2S) for confined space entry compliance. The MP400P has pumped sampling and offers a full range of over 30 sensor options, including electrochemical (EC), pellistor, non-dispersive infrared (NDIR) and photo-ionization detector (PID). With 4 sensor slots the use of combination sensors allows up to 6 gases to be measured. The MP400S and MP400H are used in wireless communication systems for real-time monitoring of gas readings and alarm status, including man-down alarm, from remote locations for better visibility and faster response. One MP400H head monitor communicates with up to 7 MP400S Soldiers. Contact us for larger wireless systems with up to 32 monitors


Diffusion sampling
• Battery operation 16 hours
• Durable double shot outer case
• 360-Degree LED alarm bar
• Man-Down alarm
• USB Micro charger & communications cable
• Flip screen
• Integrated calibration cup
• Smart sensors carry ID and calibration
• 6 Months continuous datalogging
• Modular design


• Industrial hygiene
• Oil and gas
• Fire ground “Toxic Twins” detection
• Environmental
• Chemical
• Pharmaceutical
• Telecommunications



General Specifications

Size5.74 x 3.31 x 1.65 in (140 x 84 x 42 mm)
Weight13.5 oz (384 g)
Sensors• Electrochemical for O2, CO and H2S • Pellistor for LEL
BatteryRechargeable Li-ion pack: ≥16 hours
Direct Readout• Real-time reading of gas concentration • visual compliance indicator • battery status • datalogging on/off • STEL, TWA, peak and minimum values • Man-Down alarm on/off
Display128 x 128 graphical LCD, 1.77 x 1.73 in (45 x 44 mm), with LED backlight for enhanced display readability. Automatic screen “flip” feature
Keypad2 Operation keys
CalibrationManual calibration. CaliCase option allows automatic bump test and calibration on up to 4 units simultaneously
Alarms• Audible (90 dB @ 30 cm) • Visual (flashing bright red LEDs) • Vibration • On-screen indication of alarm conditions • Man-Down alarm
DataloggingContinuous datalogging (6 months for 4 sensors at 1 minute intervals, 24 hours/day and 7 days/week)
Charging and CommunicationCharging, data download, instrument setup and firmware upgrades on PC or laptop via PC comm, cradle, travel charger, or CaliCase
Temperature-4° to 122°F (-20° to 50°C)
Humidity0% to 95% Relative humidity (non-condensing)
IP RatingIP-67
Safety CertificationsClass I, Div 1, Group ABCD (pending) T4, -20°C ≤ Tamb ≤ +50°C Ex ia IIC T4 Ga (pending) II 1G Ex ia IIC T4 Ga (pending) European Conformity (pending) UL Listed
EMC/RFIEMC directive: 2004/108/EC
Warranty2 Years including sensors
VersionSesor/RangePart Number
4-GasLEL 0.1 - 100% O2 0.1 - 30% H2S 0.1-100 ppm CO 1 - 1000 ppmM004-0001-000
3-GasLEL 0.1 - 100% O2 0.1 - 30% H2S 0.1-100 ppmM004-0002-000
2-GasLEL 0.1 - 100% O2 0.1 - 30%M004-0005-000
1-GasLEL 0.1 - 100%M004-0009-000

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