Hydrogen sets the gas group
Reformer, hydrotreater and hydrocracker loops all carry hydrogen, so the marking target is II 2 G Ex ib IIC T4. A device assessed only to IIB would be the wrong tool across much of a modern refinery.
Thailand · Thai Oil
Explosion proof mobile phone for Thai Oil in Thailand
Thai Oil runs the largest refinery in Thailand at Sriracha, on the Chonburi coast, and it is a site where an explosion proof mobile phone has real work to do: hydrogen at pressure, sour service and hot hydrocarbon in the same fenced plot. This page is for the HSE, instrumentation and IT teams who decide what a technician may carry into the Sriracha units. The SAMS IS-04Z1 is designed for Zone 1 and Zone 21, and it is pre-launch, so certification is still in progress. The IS-04Z1 is designed around intrinsic safety rather than a flameproof enclosure.
Launching Q4 2026 · certification programme in progress
Local approvalIECEx · TISIECEx · TISI and NBTC route in progress
AvailabilityQ4 2026via authorised distributors
Thai Oil · the site
What is classified inside the Thai Oil refinery at Sriracha
Thai Oil describes its Sriracha plant as a complex refinery with a crude capacity of 275,000 barrels a day, and the group also runs aromatics, lube base oil, power and marine businesses around it. The Clean Fuel Project announced to lift throughput towards 400,000 barrels a day adds a new crude and vacuum unit, a vacuum gas oil hydrocracker, a residue hydrocracker, a hydrogen plant, a sulphur recovery unit and a power plant fired on residue pitch, according to trade press coverage of the EPC award. For a handset that matters because the heaviest hydrogen and sour-gas service on the site is exactly the new equipment, built beside units that stay in production. Completion was reported for around 2025, so ask Thai Oil for the current status.
Operators and contractors
- Thai Oil operations
- Refinery operators and shift teams on the crude, hydroprocessing and aromatics trains at Sriracha.
- Thai Oil maintenance
- In-house inspection, instrument and rotating-equipment staff on permanent rounds.
- Clean Fuel Project EPC
- A consortium led by Petrofac with Saipem and Samsung, as reported at the 2018 contract award.
- Turnaround contractors
- Thai and regional shutdown crews who arrive under their own company equipment rules.
- Marine and tanker crews
- Staff handling product and crude transfer at the berths and offshore receiving points.
Classified units and areas
- Crude and vacuum distillation
- Fired heaters and light-end overheads; hot surfaces make the temperature class a live question.
- Hydrocracker and hydrogen plant
- Hydrogen at high pressure, the reason gas group IIC is the only sensible target.
- Sulphur recovery
- Sour gas upstream of the Claus trains, with H2S monitored constantly.
- Aromatics and paraxylene
- Benzene-rich streams where toxic exposure limits bite before flammable ones.
- Tank farm and marine terminal
- Floating-roof tanks, manifolds and loading arms along the transfer route.
Built for local conditions
What Sriracha does to a handset
Three conditions decide whether a handset lasts at Sriracha.
IP ratingIP68
Battery4,000 mAh
Camera50 MP
OSAndroid 16
Coastal heat and monsoon rain on open structures
Chonburi is hot and humid all year and the southwest monsoon arrives from May. Furnace decks, pipe racks and tank roofs have no shelter, so the IP68 sealing and rugged build are the design floor, with the certificate ambient range as the compliance figure.
A camera that policy can switch off
Refineries control photography tightly. Android 16 with Android Enterprise lets the plant push a camera policy to every enrolled unit from its existing MDM console, and withdraw it for contractors when the job finishes.
Thai Oil · working and approvals
How work is organised at Sriracha, and what Thai Oil teams would ask for
Two things run at once on a refinery site: the permanent shift pattern, and project or shutdown work layered over it. The second is where most unfamiliar handsets turn up.
Rounds, not tasks
Operators work a fixed sequence of readings and valve checks across a large plot, with the control room and a safe-area charging point a drive away. The 4,000 mAh battery is specified to cover a full shift with the camera, GNSS and radio app running, which is how rounds are actually done.
Project and turnaround crews
A construction programme beside live units means many contractor firms sharing the same classified boundaries as operations.
Vendor and equipment approval
We have not verified a published Thai Oil programme for portable electronics, so we do not describe one. The sensible route is to ask Thai Oil procurement and HSE for the equipment approval steps, the documents expected with an Ex certificate, and whether the unit needs to be assessed for the specific zone before it is issued.
Thai Oil · use cases
Where the IS-04Z1 explosion proof mobile phone goes to work.
Operations01
Hydroprocessing unit rounds
An operator walks a hydrocracker or hydrotreater route, records readings and photographs a weeping flange without leaving the classified area. The photograph and the GNSS position go straight onto the notification, so the planner sees the fault and where it is.
Maintenance02
Hot-work permits and gas-test records
A permit receiver on a turnaround job needs the gas test result and the permit in front of them at the vessel, not at the permit office. A managed handset carries the approved permit app and a site directory and can be locked down once the job is signed off.
Marine03
Jetty and offshore receiving points
Transfer crews work far from the control room, on decks and walkways with no landmarks to describe a position by. Four-constellation GNSS puts a fix on the record and the IP68 body copes with spray and rain during a transfer.
Questions · Thai Oil
Frequently asked questions
Can Thai Oil buy an explosion proof mobile phone from SAMS today?
No. The IS-04Z1 is pre-launch with a Q4 2026 launch, and IECEx, ATEX and NEC 500 certification are in progress. A reviewer can have the datasheet and the certification schedule now, but nothing is issued into a classified area before the covering certificate exists.
Which refinery units is the handset designed for?
Zone 1 gas areas and Zone 21 dust areas, gas group IIC, with a temperature class target of T4. That covers hydrogen service, light ends and sour areas. Whether it is accepted in a given unit is for Thai Oil engineering and HSE to decide against the certificate once it exists.
Does a sulphur or catalyst block need anything different?
Sulphur recovery and catalyst handling mix sour gas with fine solids, so both Zone 1 and Zone 21 considerations can apply close together. The design target covers both, but the area classification drawings for the specific block govern which zone applies where.
Enquiry · Thai Oil
Ask about the IS-04Z1 for Thai Oil, Thailand
Tell us the site, the zone and gas group, and roughly how many handsets. The SAMS team replies by email with the datasheet and the certification schedule for Thailand. The IS-04Z1 is pre-launch and certification is in progress, so there is no list price yet; indicative pricing is issued in writing against a stated quantity and site.
Enquiry · Thai Oil
Launching Q4 2026
Evaluating the IS-04Z1 for this site?
Tell us the zone, gas group and operator. We will send the datasheet and the certification schedule for your market.