The POLI MP400 is a 4-gas detector with diffusion sampling designed for worker safety during confined-space entry and hazardous location work.
The POLI MP400 is a basic 4-gas detector designed for worker safety in hazardous locations, featuring sensors for oxygen (O₂), combustibles (LEL), carbon monoxide (CO), and hydrogen sulfide (H₂S). A hydrogen cyanide (HCN) version and 5-gas version with sulfur dioxide (SO₂) are also available. The monitor features extremely rugged construction with a robust double-shot outer case, diffusion sampling with no moving parts, and simple 2-button operation for ease of use and reduced training time. It includes a rechargeable Li-ion battery lasting 16+ hours, unique Man-Down alarm feature to notify workers if the user becomes incapacitated, 360-degree LED alarm bar, flip screen, 6-month continuous datalogging, and modular design. Equipped with USB Micro charger/communications cable and integrated calibration cup.
| Performance | |
| Sensors | Electrochemical forO2,CO,H2S和HCNPellistor forLEL |
| ResponseTime(t90) | 15 s(LEL/CO/H2S/O2)30 s(CO/H2S combination sensor)60 s(HCN) |
| Display | 128x128graphicalLCD,1.77x1.73in(45x44mm),withLEDbacklightforenhanceddisplayreadabilityAutomatic screen"flip"feature |
| Alarms | Audible(95dB@30cm)Visual(flashingbrightredLEDs)VibrationOn-screenindicationofalarmconditionsMan-Downalarm |
| Power | |
| Battery | RechargeableLi-ion pack:≥16 h |
| Physical | |
| Size | 5.74x3.31x1.65in(140x84x42mm) |
| Weight | 13.5oz(384g) |
| Connectivity | |
| Datalogging | Continuousdatalogging(6monthsfor4sensorsat1minuteintervals,24 h/dayand7days/week) |
| Approvals & Warranty | |
| IP Rating | IP-67 |
| SafetyCertifications | ClassI,Div1,GroupABCDT4,-20°C≤Tamb≤+50°CExiaIICT4GaII1GExiaIICT4GaEuropeanConformity |
| Warranty | 2Yearsincludingsensors |
| Other | |
| Keypad | 2Operation keys |
| Temperature | -4°to122F(-20°to50℃) |
| Humidity | 0%to95%Relativehumidity(non-condensing) |
| EMC/RFI | EMC directive:2014/30/EU |
Calibration, repair and maintenance for your detection instruments.



