The reliability of the IRmax hydrocarbon detector has been proven in hot, cold, wet and saline environments, making it ideal for offshore. 
IRmax’s unique Stay Clir optical components are treated with a highly durable coating that completely prevents faults due to condensation. As IRmax contains no components for artificially heating optical surfaces, power consumption is dramatically reduced, requiring only 1W of power.

Simple to install

  • Compact size – requires less space, effort and time to install
  • Various installation options – can be wall mounted, fitted to a 50mm (2 inch) pipe or connected to an auxiliary junction box using a choice of mounting accessories
  • Industry standard 4-20mA output – compatible with virtually any control system
  • Options for HART communications and RS-485 Modbus

Easy maintenance

  • Remote non-intrusive calibration – the remote display can be mounted up to 30 metres from the IRmax and test gas can be applied without requiring direct access to the detector
  • Hand-held Intrinsically Safe (I.S) calibrator – IRmax fixed gas monitors fitted with an I.S barrier module can be checked and calibrated using an I.S handheld display
  • STAY-CLIR optics – prevents condensation on optical components

Low cost of ownership

  • Low power – only consumes 1W of power, enabling small power supplies and battery back-up systems to be used
  • Automatic optical obscuration monitoring – minimal routine maintenance keeps costs down
  • Annual proof-test interval


IRmax IRmax with Fixed IR display IRmax with IS Barrier Module Remote IR Display
Size 158 x 75 x 57mm (6.2 x 2.9 x 2.3ins) 230 x 75 x 57mm (9 x 2.9 x 2.3ins) 261 x 75 x 57mm (2.3 x 2.9 x 2.3ins) 60 x 54 x 48mm (2.3 x 2.1 x 1.9ins)
Weight 1.58kg (3.5lbs) 2kg (4.4lbs) 2.4kg (5.3lbs) 0.2kg (0.4lbs)
Ingress protection IP66
Enclosure material 316 stainless steel
Power 12-30 Vdc. < 1W
Connection One M20 or 1/2” NPT cable gland entry
Electrical output 4-20mA current sink or source
2mA dirty optics warning (at 75% obscuration, configurable)
0mA detector fault signal (at 90% obscuration, configurable)
RS-485 Modbus (optional), HART 7 (optional)
Operating temperature -40°C to +75°C (-40°F to 167°F)
Humidity 0 to 95% RH non-condensing
Pressure range Atmospheric +/- 10%
Repeatability +/- 2% FSD
Zero drift +/- 2% FSD per year maximum
Response time T-90 <4 seconds
Functional safety Validation to IEC61508, EN50402 SIL 2
Approvals Ex II 2 GD
Exd IIC T6 Gb (Tamb -40to+50°C),
T4 (Tamb -40to+75°C)
Ex tb IIIC T135°C Db (Tamb -40 to +75°C)
Ex II 2 G
Exd ia IIC T4 Gb (Tamb -40to+75°C)
Ex II 2 GD
Exd ia IIC T4 Gb (Tamb -40to+75°C)
Ex tb IIIC T135°C Db (Tamb -40 to +40°C)
EMC compliance Directive 2014/30 EU: EN50270, FCC CFR47 Part 15B, ICES-003
Zones Certified for use in Zone 1 & 2.


Safety Integration LevelHART communications protocolStay-Clir


Below is a small selection of the accessories available for the IRmax.

Sun Shade/Collector Cone


Stainless steel accessory protects against elevated temperatures due to direct sunlight and extends the detector footprint for detecting lighter than air gases.

Sun Shade


Stainless steel accessory protects against elevated temperatures due to direct sunlight and extends the detector footprint for detecting lighter than air gases.

Mounting bracket kit


Enables mounting to a wall or 2″ (50mm) pipe. Comprises: bracket, straps/nuts/bolts for pipe-mounting. (Not required if IRmax is being fitted to a junction box using a spigot gland.) Wall-mounting fixings must be supplied by the installer.

Stainless steel pipe mounting bracket kit


Supplied with stainless steel u-bolts to enable IRmax to be rigidly mounted to a 50mm (2″) pipe.

Spigot gland (M20)


Enable IRmax to be connected to an auxiliary junction box. 5-wire, ATEX and IECEx certified.

Duct mounting kit


Enable monitoring of ducts measuring from 300mm to 3 metres wide, air-flows from 4 to 20 metres per second. Supplied with mounting flange (stainless steel) and tube which is to be cut so that it protrudes half-way across the duct.

Remote calibration box (GRP)


Suitable for use in offshore environments and enables remote calibration of IRmax via connection of a hand-held IR Display and test gas. GRP (glass-fibre reinforced polyester) enclosure fitted with lead connectors and a retaining clip for an IRmax remote calibration pipe. Requires an I.S. connecting lead, and the IRmax detector must be fitted with an I.S. Barrier Module.

Calibration cap


Fits over the standard weatherproof cap to enable calibration where local air speed exceeds 2 metres per second.

Flow adaptor


Replaces standard weatherproof cap for gas sampling applications.

PC Communications kit


Communications module supplied with a software CD and USB cables for PC and IRmax detector connection. Enables zeroing, calibration, gas type changes etc. Not suitable for use in a hazardous area.

316 stainless steel Exd junction box


Enables IRmax to be connected on an RS-485 Modbus network. Two cable gland entries, five terminals suitable for 2.5mm2 cables. A Spigot Gland is required if IRmax is to be connected directly. ATEX/IECEx certified for Gas and Dust hazardous areas.

GRP Exe junction box


Provides compliance with NORSOK standards, which stipulate detectors must have an Exe cable termination area. GRP Exe junction box with one cable gland entry on the left-side, fitted with a six-way terminal block suitable for 2.5mm2 cables. A Spigot Gland is required if IRmax is to be connected directly.