Environmental Monitoring Equipment & Supplies • Sales, Rental & Service by Enviro-Equipment — Charlotte, North Carolina USA

RAE Systems MultiRAE Plus 4 Gas Meter with PID
  • O2, LEL, PID and any two plug-in “smart” toxic sensors: CO, H2S, SO2, NO, NO2, Cl2, HCN, NH2, PH2
  • 0 - 2000 ppm measurements of VOCs
  • Measure more chemicals than with any other PID
  • Drop-in Battery
  • Strong, Built-in sample up draws up to 100 ft.
  • Audible alarms

This item is no longer available.

Designed as a "building block" system, the MultiRAE can be configured from a simple, inexpensive Oxygen/LEL combustible gas monitor all the way to an affordable five gas monitor for total protection in toxic environments. The MultiRAE is easily reconfigured and upgraded to meet your changing needs. MultiRAE's versatility allows it to replace a wide range of monitors, saving training and maintenance costs. The MultiRAE is quickly and easily changed from a sophisticated technician instrument to a simple text or display only monitor. The monitor can be used as personal monitor, a hand-held sniffer, or area monitor.

Most confined space monitors provide less than total protection because they miss many toxic vapors and gases. LEL sensors measure explosivity, not toxicity. Many Volatile Organic Compounds (VOCs) are potentially toxic at levels that are well below the sensitivity of the LEL sensors found in most multi-gas monitors. For example by the time that LEL sensors even respond to gasoline vapors the air is already toxic!

The MultiRAE accurately measures low levels of VOCs without the annoyance of false alarms that are so prevalent with other "broad-band" sensors. Its patented VOC monitor, measures 0 - 2000 ppm of VOCs' while providing continuous display and alarms for worker protection. Alarms can also be set for Short Term Exposure Levels (STEL), Time Weighted Average (TWA), Peaks and Minimums.

The MultiRAE displays the exact airborne VOC levels so that you do not have to guess when to put on respiratory protection. With the MultiRAE you work safer, more efficiently and more comfortably because you can go longer without respiratory protection with complete confidence you are working in clean air.

The MultiRAE Plus 4 gas detector comes standard with the oxygen sensor (O2), combustible sensor (LEL), and photoionization detector lamp (PID). These additional sensors are available:

  • carbon monoxide sensor (CO sensor)
  • hydrogen sulfide sensor (H2S sensor)
  • sulfur dioxide sensor (SO2 sensor)
  • nitric oxide sensor (NO sensor)
  • nitrogen dioxide sensor (NO2 sensor)
  • chlorine sensor (Cl2 sensor)
  • hydrogen cyanide sensor (HCN sensor)
  • ammonia sensor (NH3 sensor)
  • phosphine sensor (PH3 sensor)

Gas Monitor




0 - 30%


Combustible Gas

0 - 100% LEL

1% LEL

Carbon Monoxide

0 - 500 ppm

1 ppm

Hydrogen Sulfide

0 - 100 ppm

1 ppm


0 - 200 ppm
200 - 2000 ppm

0.1 ppm
1 ppm

Sulfur Dioxide

0 - 20 ppm

0.1 ppm

Nitric Oxide

0 - 250 ppm

1 ppm

Nitrogen Dioxide

0 - 20 ppm

0.1 ppm


0 - 10 ppm

0.1 ppm

Hydrogen Cyanide

0 - 100 ppm

1 ppm


0 - 50 ppm

1 ppm


0 - 5 ppm

0.1 ppm


4.65"L x 3.0"W x 1.9"H (11.8 x 7.6 x 4.8 cm)


16 oz.with battery (454g)

Direct Readout

  • Oxygen as percentage by volume
  • Combustible gas as percentage of lower explosive level (LEL)
  • Carbon Monoxide, Hydrogen Sulfide and VOCs as parts per million (ppm)
  • High and low values for all gases
  • STEL and TWA values of toxic gases and VOCs
  • Battery and shut down voltage
  • Date, time, elapsed time, temperature


Lithium-ion battery pack with internal smart charging, 120V AC/DC wall adapter

Operating Hours

14 hours continuous with Li-ion (typical), unit will run and charge simultaneously


2 line, 16 digit LCD with LED backlighting automatically in dim light or alarm condition


-4° to 113 °F (-20 to 45°C)


0% to 95% relative humidity (non-condensing)


90 dB buzzer and flashing red LED to indicate exceeded preset limits:

  • High: 3 beeps and flashes per second
  • Low: 2 beeps and flashes per second
  • High and low values for all gases
  • STEL and TWA: 1 beep and flash per second
  • Additional diagnostic alarms and display messages for low battery and pump stall


Highly resistant to EMI/RFI. Compliant with EMC Directive 89/336/EEC

IP Rating

IP-55: protected against dust, protected against low pressure jets of water from all directions

Data Logging

80 hours, 5 channels at one minute intervals download to PC with serial number of unit, user ID, site number, and calibration date


Zero & Span Calibration (programmable)

Sampling Pump

250 cc/min

Low Flow Alarm

Auto shut-off pump at low flow condition

Hazardous Area Approval

  • US and Canada: UL, cUL, Classified as Approval Intrinsically Safe for use in Class I, Division I Groups A, B, C, D, T3C
  • Europe: ATEX II 2G EEx ia d IIC T3 & T4


Durable yellow boot with belt clip and wrist strap; Shoulder strap; optional tripod/wall mounting bracket