The Crowcon T4 and T4x are personal 4 gas monitors for the four most common gas hazards: oxygen depletion, flammable gas, hydrogen sulphide and carbon monoxide. We supply both models, with the bump test gas and calibration that keep them ready for every shift.
| Gases and ranges | Oxygen 0 to 30% vol, flammable 0 to 100% LEL, hydrogen sulphide 0 to 100 ppm, carbon monoxide 0 to 1000 ppm |
|---|---|
| Configurations | 2, 3 or 4 gas |
| Battery | Rechargeable Li-ion. T4: up to 18 hours. T4x: up to 35 hours with the MPS sensor fitted. 5.5 hour recharge |
| Ingress protection | Independently tested to IP65 and IP67 |
| Durability | Drop tested to 4 m onto concrete, integrated rubber boot as standard |
| ATEX and UKCA | T4: II 2 G Ex db ia IIC T4 Gb. T4x: II 1 G Ex ia IIC T4 Ga. Both -20°C to +55°C |
| IECEx | T4: Ex db ia IIC T4 Gb. T4x: Ex ia IIC T4 Ga |
| Weight | 282 g |
| Bump and calibration | Bump/calibration plate included. I-Test automated bump test and calibration station available separately |
| Data logging | 130 hours at 10 second intervals, 3,500 events |
Crowcon built the T4 to cover the four gases most often found on site in one simple device. It can be set up as a 2, 3 or 4 gas monitor:
Both share the same size, weight and controls. The differences are in the sensors, the battery and the hazardous area approval.
The T4x can be fitted with Crowcon’s MPS flammable sensor, which Crowcon says has zero risk of poisoning and can identify over 15 different flammable gases. It also offers a long-life oxygen sensor and a dual toxic sensor for CO and H2S. With the MPS sensor fitted, Crowcon quotes up to 35 hours of run time, double the original T4, so multiple or longer shifts can be worked between charges.
The T4x is Crowcon’s Zone 0 approved personal monitor, marked ATEX II 1 G Ex ia IIC T4 Ga. The T4 is marked II 2 G Ex db ia IIC T4 Gb. Our guide to ATEX zones explains what those categories mean for where a monitor can be used.
Crowcon calls the T4 its toughest portable. It is drop tested to 4 m onto concrete, independently tested to IP65 and IP67, and comes with an integrated rubber boot. A clip-on filter plate protects the sensors in dusty conditions. The large single button and simple menu work with gloves on.
The T4 also has a TWA Resume function. It keeps toxic gas exposure calculated across a whole shift, even if the monitor is switched off for a break or while travelling between sites. For what a 4 gas monitor needs to do before and during entry into tanks and chambers, see our page on confined space gas monitors.
Every T4 and T4x comes with a bump/calibration plate. For larger fleets, Crowcon’s I-Test station automates bump tests and calibration. We supply the bump test gas and regulators to suit your sensor setup, and we provide gas detector calibration with a certificate for each unit, including T4s bought elsewhere.
A portable detector that measures oxygen, flammable gas as % LEL, carbon monoxide and hydrogen sulphide at the same time. These are the hazards most often found in tanks, chambers, sewers and plant rooms. The Crowcon T4 and T4x are both 4 gas monitors.
Crowcon quotes up to 18 hours for the T4. The T4x runs for up to 35 hours with the MPS sensor fitted. Both recharge in 5.5 hours.
Yes. Crowcon’s I-Test station runs automated bump tests and calibration for the T4 range. A manual bump/calibration plate also comes with every unit.
Yes. Our engineers service and calibrate gas detectors from many manufacturers. Tell us the model and how many units you have when you book.
Tell us how many monitors you need and what work they will be used for, and we will recommend the T4 or T4x with test gas to match. Call 01 289 7720 or email info@vistec.ie.
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Descriptions
