What Is an Intrinsically Safe Phone?
A plain-language guide to ATEX and IECEx certification for mobile phones in hazardous areas — written for HSE engineers, procurement, and operations teams.
The short answer
An intrinsically safe (IS) phone is a mobile device certified to operate in explosive atmospheres — environments where flammable gases, vapours, or combustible dust are present. The device is engineered so that its electrical circuits cannot produce enough energy (sparks or heat) to ignite the surrounding atmosphere.
Certification is granted under two frameworks:
- ATEX — the EU directive (2014/34/EU) mandatory within the European Economic Area
- IECEx — the international certification scheme, accepted in most countries worldwide
Why can't I use a normal phone?
Standard smartphones contain multiple ignition sources:
- Battery — lithium-ion cells store significant energy; damage or short circuits can cause thermal runaway
- Charging port — making/breaking electrical connections creates sparks
- Camera flash — high-intensity discharge in a fraction of a second
- Processor and radio — surface temperatures can exceed ignition thresholds for certain gas groups
In a Zone 1 environment (explosive atmosphere likely during normal operations), any of these could trigger an ignition event. IS certification ensures that energy levels across all circuits stay below the minimum ignition energy of the target gas group.
Zone classification: Zone 0, 1, and 2
Hazardous areas are classified by how frequently an explosive atmosphere is present:
| Zone | Gas/vapour frequency | Typical locations |
|---|---|---|
| Zone 0 | Continuously or for long periods | Inside tanks, vessels, pipelines |
| Zone 1 | Likely during normal operations | Near vents, flanges, pump seals, loading areas |
| Zone 2 | Not likely, only under abnormal conditions | Areas adjacent to Zone 1, well-ventilated process areas |
A Zone 1 certified device can also be used in Zone 2. A Zone 2 device cannot be used in Zone 1. Most IS phones target Zone 1 certification as it covers the broadest range of deployment scenarios.
ATEX vs IECEx: what's the difference?
| Aspect | ATEX | IECEx |
|---|---|---|
| Scope | European Economic Area (EU/EEA) | International (50+ countries) |
| Legal basis | EU Directive 2014/34/EU | IEC standards scheme |
| Mandatory? | Yes, within the EEA | Accepted, not always mandatory |
| Marking | CE + Ex hexagon | IECEx certificate number |
| Mutual recognition | Within EEA only | Across participating countries |
Many manufacturers certify under both ATEX and IECEx to enable worldwide deployment. If your operations span multiple regions, look for dual-certified devices.
Gas groups: IIA, IIB, IIC
Not all explosive gases are equally easy to ignite. Gas groups classify substances by their minimum ignition energy:
| Gas group | Example gases | Ignition difficulty |
|---|---|---|
| IIA | Propane, methane, diesel | Hardest to ignite |
| IIB | Ethylene, hydrogen sulphide | Medium |
| IIC | Hydrogen, acetylene | Easiest to ignite |
A device certified for IIC can be used in IIA and IIB environments. A device certified only for IIA cannot be used where IIB or IIC gases are present. Most modern IS phones target IIC to cover the widest range of applications.
Two approaches: Ex case vs dedicated Ex phone
Certified Ex case
A protective enclosure that makes a standard consumer phone (typically iPhone) compliant for hazardous areas. The case controls energy pathways, seals ignition sources, and carries its own ATEX/IECEx certification.
- Advantages: Familiar iOS/Android UX, consumer-grade camera and apps, easy MDM integration, users already know how to use it
- Trade-off: Added bulk from the case, limited to specific phone models
- Example: Xshielder (iPhone, Zone 1, IIC, ATEX + IECEx)
Dedicated Ex phone
A purpose-built smartphone designed from the ground up for hazardous areas. Every component is selected for Ex compliance.
- Advantages: No external case needed, often more rugged (high IP ratings), some models include barcode scanners or PTT
- Trade-off: Typically runs Android with limited app ecosystem, lower camera quality, less familiar UX, longer procurement cycles
- Examples: ecom Smart-Ex 03 DZ1, Bartec SP9EX1, i.safe MOBILE IS540.1
How to choose the right IS phone
Consider these factors when selecting an intrinsically safe phone for your site:
- Zone classification — what zones exist on your site? Zone 1 devices cover Zone 2 as well.
- Gas group — which gases are present? IIC covers all groups.
- Regional certification — do you need ATEX, IECEx, or both?
- Operating system — does your workforce need iOS apps or is Android acceptable?
- Integration — does the device need to work with existing MDM, ERP, or inspection software?
- Camera requirements — do field workers need high-quality photos for inspections?
- Total cost of ownership — dedicated devices are more expensive upfront; cases allow consumer phone refresh cycles.
Frequently asked questions
Can I use a normal iPhone in a hazardous area?
No. Standard iPhones are not certified for explosive atmospheres. You need either a certified Ex case (like Xshielder) or a dedicated Ex phone. Using an uncertified device in a classified area violates ATEX/DSEAR regulations and risks explosion.
What is the difference between Zone 1 and Zone 2?
Zone 1 means an explosive gas atmosphere is likely during normal operations. Zone 2 means it only occurs under abnormal conditions. Zone 1 devices require stricter certification but can also be used in Zone 2 areas.
Is ATEX the same as IECEx?
No. ATEX is the EU regulatory framework (mandatory in the EEA). IECEx is the international certification scheme. They share the same underlying IEC 60079 standards, but are administered separately. Many devices carry both certifications.
How much does an intrinsically safe phone cost?
Pricing varies by manufacturer and certification scope. Total cost of ownership should include the device refresh cycle, repair/service costs, and MDM licensing. Inquire here for current pricing.