This glossary is designed to be your essential one-stop shop for demystifying the complex terminology and abbreviations that define the hazardous area landscape.
We’ve organized the most critical concepts into a logical flow to help you understand the key concepts, and how they pertain to the mobile technology that powers your field operations.
This section defines the legal and international frameworks that mandate safety standards in hazardous locations.
|
Term |
Category |
Detailed Definition |
|
ATEX |
Regulatory |
The European Union framework (Directives 2014/34/EU and 1999/92/EC) for equipment and worker safety. Mandatory for products sold in the EU. |
|
IECEx |
Regulatory |
An international certification scheme based on IEC standards. It aims to harmonize "Ex" standards globally to facilitate international trade. |
|
Hazardous Area |
Environment |
Any location where flammable gases, vapors, mists, or dusts can mix with air to create an explosive atmosphere under atmospheric conditions. |
|
Notified Body |
Authority |
An independent, accredited organization (e.g., Intertek, SGS, UL, CSA) that audits manufacturers and issues "Ex" certificates. |
Zones are the first step in risk assessment. They define how likely an explosion is to occur based on time and frequency.
|
Zone (Gas) |
Zone (Dust) |
Occurrence Frequency |
Frequency Detail |
|
Zone 0 |
Zone 20 |
Continuous |
Hazard is present constantly or for long periods (>1,000 hours/year). |
|
Zone 1 |
Zone 21 |
Occasional |
Hazard is likely to occur during normal daily operations (10–1,000 hours/year). |
|
Zone 2 |
Zone 22 |
Rare |
Hazard is unlikely to occur; if it does, it persists for a very short time (<10 hours/year). |
Even if a Zone is "Rare," you must know "What" is in the air. This section classifies substances by how easily they ignite.
|
Group |
Representative Substances |
Relative Hazard |
|
Group I |
Methane, Coal Dust (Firedamp) |
Underground Mining Only |
|
Group IIA |
Propane, Petrol, Acetone, Ammonia |
Low (Highest energy required to ignite) |
|
Group IIB |
Ethylene, Town Gas, Coke Oven Gas |
Medium |
|
Group IIC |
Hydrogen, Acetylene, Carbon Disulphide |
Highest (Extremely easy to ignite) |
|
Group IIIA |
Combustible Flyings (Cotton, Rayon, Lint) |
Low |
|
Group IIIB |
Non-Conductive Dust (Grain, Sugar, Wood, Flour) |
Medium |
|
Group IIIC |
Conductive Dust (Aluminum, Magnesium, Graphite) |
Highest (Conductivity increases risk) |
Applies to Gas environments. The device surface must never exceed the Auto-Ignition Temp (AIT) of the gas.
|
T-Class |
Max Surface Temp |
Example Substances |
|
T1 |
450°C |
Methane, Hydrogen |
|
T2 |
300°C |
Ethanol, Butane |
|
T3 |
200°C |
Petrol, Diesel, Jet Fuel |
|
T4 |
135°C |
Standard for most mobile devices/tablets. |
|
T5 |
100°C |
N/A (Less common requirement) |
|
T6 |
85°C |
Maximum Safety (e.g., Carbon Disulphide). |
This is the core "How." These engineering philosophies determine whether a device prevents an explosion or simply survives one.
|
Philosophy |
Principle |
Context for Mobile Devices |
|
Intrinsically Safe (IS) |
Prevention: Limits the energy (current/voltage) to ensure no spark or heat can occur. |
Found in Native Ex iPhones/Androids. Allows for light, slim devices. |
|
Explosion Proof (Ex-Proof) |
Containment: Uses a heavy-duty enclosure to contain an internal blast and cool flames. |
Usually found in Ex Cases. Results in heavier, bulkier equipment. |
|
Code |
Name |
Principles / Fault Tolerance |
Typical Zones |
|
Ex ia |
Intrinsic Safety |
Safe with two simultaneous component faults. |
0, 1, 2 |
|
Ex ib |
Intrinsic Safety |
Safe with one component fault. |
1, 2 |
|
Ex ic |
Intrinsic Safety |
Safe during normal operation (no faults). |
2 |
|
Ex d |
Flameproof |
Enclosure withstands internal pressure; cools exiting gases. |
1, 2 |
|
Ex e (eb, ec) |
Increased Safety |
Robust construction; prevents arcs/sparks from starting. |
1, 2 |
|
Ex m (ma, mb) |
Encapsulation |
Electronics "potted" in resin to exclude gas/dust. |
0, 1, 2 |
|
Ex p (px, py, pz) |
Pressurized |
Clean air/inert gas keeps hazardous air out. |
1, 2 |
|
Ex t (ta, tb, tc) |
Dust Tight |
Protection by enclosure specifically for dust layers/clouds. |
20, 21, 22 |
|
Ex n (nA, nR) |
Non-Sparking |
Low-cost method specifically for Zone 2. |
2 |
This is the "decoder ring" for the stickers found on the back of iPads and iPhones.
|
Code / Suffix |
Meaning |
Detailed Context |
|
Category 1 / 2 / 3 |
ATEX Level |
1: Zone 0/20; 2: Zone 1/21; 3: Zone 2/22. |
|
EPL (Ga, Gb, Gc) |
IECEx Level |
Ga: Highest Gas protection; Gc: Normal Gas protection. |
|
EPL (Da, Db, Dc) |
IECEx Level |
Da: Highest Dust protection; Dc: Normal Dust protection. |
|
X-Condition |
Specific Rule |
Found at end of Cert #. Means you must read the manual (e.g., "Charge only with Brand X cable"). |
|
U-Component |
Incomplete Part |
Found at end of Cert #. Means the part is not safe to use unless built into a system. |
|
CE + 4 Digits |
Notified Body |
e.g., "CE 0539" (UL). Confirms the factory is audited for Ex production. |
Specific jargon related to the physical build of mobile devices and their environmental durability.
|
Term |
Hardware Type |
Definition |
|
Native Ex Device |
Smartphone/Tablet |
A device engineered internally to be Ex i. Usually thinner and lighter. |
|
Ex Case |
Accessory |
A certified housing (often Ex d or Ex t) that makes a consumer device safe. |
|
Ruggedized |
Durability |
Refers to drop/shock resistance (MIL-STD-810H). Does not mean it is ATEX certified. |
|
IS-Barrier |
Charging |
A safety circuit in a "Safe Area" that cleans power before it enters an Ex device. |
|
IP67 / IP68 |
Sealed |
6: Dust-tight (Mandatory for most dust zones); 7/8: Immersion in water. |
|
Antistatic |
Material |
Materials (often on iPad cases) designed to prevent the buildup of static electricity. |
CE 2460 Ex II 2 G Ex ib IIC T4 Gb