ATEX radios: zones, marking and Motorola models

What ATEX and IECEx are

ATEX is the European framework for equipment used in potentially explosive atmospheres (Directive 2014/34/EU). IECEx is the equivalent international certification scheme. A radio certified to ATEX and IECEx is designed and tested so that, within the limits of its marking, it cannot cause ignition.

The Motorola DP4401Ex and DP4801Ex are "intrinsically safe" (Ex ib): they limit the energy in their circuits so that neither a spark nor heat reaches a level that ignites a flammable mixture.

The zones in plain words

For gases, vapours and mists, areas are classified as zone 0 (explosive atmosphere present continuously or for long periods), zone 1 (likely in normal operation) and zone 2 (unlikely, and if it occurs, only briefly). For combustible dust, the matching zones are 20, 21 and 22.

Each zone allows equipment of a certain category: category 1 for all zones, category 2 for zones 1/21 and 2/22, and category 3 only for zones 2/22. Your site’s classification is made by the safety officer and is the basis for every choice.

How to read the marking

The Motorola DP4401Ex and DP4801Ex carry the marking II 2G Ex ib IIC T4 Gb. II means equipment for use outside mines, 2G category 2 for gases (zones 1 and 2), Ex ib intrinsic safety, IIC the most demanding gas group (such as hydrogen and acetylene), T4 a maximum surface temperature of 135 °C and Gb the equipment protection level for zone 1.

For dust they carry II 2D Ex ib IIIC T130°C Db: category 2 for zones 21 and 22, group IIIC (conductive dust, the most demanding) and a maximum surface temperature of 130 °C. The marking I M2 Ex ib I Mb covers mines. The R7Ex is certified for gas zones 1/2 and dust zones 21/22.

The models

The DP4401Ex is Motorola’s core ATEX radio: 32 channels without a display, IP67, Man Down, Lone Worker, GPS and, according to Motorola, up to 19 hours in digital mode. We sell it on VHF and UHF. The DP4801Ex has the same base with a five-line colour display, a keypad and 1000 channels, for supervisors and large sites. The R7Ex is the newest, with audio up to 108 phon, AI noise suppression, IP66/IP68, Bluetooth 5.2, Wi-Fi and four satellite positioning systems.

Batteries, accessories and charging

In a hazardous zone, use only the ATEX batteries and accessories the manufacturer specifies for that model. For the DP4401Ex and DP4801Ex we sell the NNTN8359 2075 mAh IMPRES ATEX battery. An ordinary earpiece or battery is not covered by the radio’s certification.

Follow the manufacturer’s instructions on where charging and battery changes are allowed; they usually ask for this to be done outside the hazardous zone.

EETT licence and programming

ATEX radios are DMR radios on licensed VHF or UHF frequencies, so you need a frequency assignment from EETT. We help with the application and deliver the radios programmed with your frequencies, so they also talk to the site’s other radios on the same channels.

Which ATEX radio for whom

For shift staff who need a simple radio with few channels, the DP4401Ex, on your licence band. For supervisors, emergency teams and large sites with many groups, the DP4801Ex with its display and keypad. For very noisy places, such as pump houses and compressors, the R7Ex with audio up to 108 phon and AI noise suppression. All three talk to the site’s other MOTOTRBO radios on the same channels.