GS Caltex
The Yeosu Complex covers about 6 million square metres, with a mixed feed cracker completed in November 2022 producing 900,000 tonnes of ethylene a year.
Yeosu is a south coast city of about 269,000 people hosting a major refining and petrochemical complex. GS Caltex's Yeosu Complex and Lotte Chemical's Yeosu plant create large Zone 1 and Zone 2 areas. If you are specifying an intrinsically safe mobile phone for Yeosu, this page covers the markings, the approvals and the current certification status of the IS-04Z1.
Pre-launch · certification in progress · Launching Q4 2026
Short answer. The SAMS IS-04Z1 is the intrinsically safe smartphone covered here for Yeosu: pre-launch, designed for Zone 1 and Zone 21 (marking target Ex ib IIC T4), with certification in progress and no certificate issued.
Where things stand: the IS-04Z1 has not launched, and none of its four certification routes has produced a certificate yet. An operator's own vendor approval is a separate step. Certification status. Place facts reviewed October 2026.
| Check | What to look for | IS-04Z1 today |
|---|---|---|
| Level of protection | ia, ib or ic matched to the zone | ib, for Zone 1 |
| Entity parameters | Uo, Io and Po within the device limits | Published with the certificate |
| Accessories | Chargers and cases certified with the device | Defined at certification |
| Where it applies | Yeosu: Refinery process units, Ethylene cracker and polymer plants, Chemical storage tank farms | Classified by the site operator |

An intrinsically safe Android smartphone designed for Zone 1 and Zone 21 hazardous areas in Yeosu. It is pre-launch: IECEx, ATEX and NEC 500 certification is in progress ahead of the Q4 2026 launch.
A short profile of the site and the kinds of classified area that matter for portable equipment.
The Yeosu Complex covers about 6 million square metres, with a mixed feed cracker completed in November 2022 producing 900,000 tonnes of ethylene a year.
Korea approved a restructuring plan in July 2026 involving Lotte Chemical's Yeosu operations and the Yeochun NCC integration.
GS Caltex concentrates its refining and petrochemical plants at the Yeosu Complex, which covers about 6 million square metres, making the complex a large single-site hazardous-area environment.
Yeosu consists of a peninsula and 365 islands, 48 of them inhabited, midway along South Korea's southern coast beside the Bay of Suncheon, with a population of about 269,000.
Yeosu has a humid subtropical climate with very warm summers and cold winters, and from June to August more than 200 mm of rain falls each month.
GS Caltex is owned in equal shares by Chevron and GS Energy and was founded in 1967 as Korea's first private oil company, so it follows long-established corporate safety systems.
Intrinsic safety limits the electrical and thermal energy in a circuit so that neither a spark nor a hot surface can ignite a gas or dust atmosphere, even when a fault occurs. The ib level, used for Zone 1, tolerates one fault. It is the usual way to make a handheld device that a worker carries continuously through a hazardous area.
The IS-04Z1 is designed on this principle for Zone 1 and Zone 21 (marking target II 2 G Ex ib IIC T4). Intrinsic safety is a design basis, not a certificate: certification is in progress and none has been issued yet.
In Yeosu. Rounds through process units, polymer plants, tank farms and marine loading jetties are long, and turnaround crews work to tight windows. A handheld intrinsically safe phone is intended for photographs, readings and checklists on those routes. Use depends on certification in progress and the plant's permits.
A short checklist for anyone writing or reviewing the specification, with the IS-04Z1 status against each point.
Not today. Until the certificates are issued the IS-04Z1 stays out of classified areas, and until launch there is nothing to purchase. You can ask for the datasheet and the certification schedule, or book a safe-area evaluation unit.
No price is published. While certification is in progress there is no list price and no committed lead time, and a supplier quoting a firm figure for an uncertified Ex handset is promising something it cannot stand behind. Indicative pre-launch pricing is issued in writing against a stated quantity and site.
The circuits are designed to limit energy so a spark or hot surface cannot ignite a gas or dust atmosphere, even with one fault (level ib, Zone 1). Certification of that design is in progress.
Likely candidates are refinery process units, ethylene cracker and polymer plants, chemical storage tank farms, marine loading jetties. Which areas are classified, and to what zone, is set by the site operator's own area classification drawings.
Not exactly. Explosion proof is a broad everyday term; intrinsic safety is one protection concept, which limits energy so ignition cannot occur. Flameproof (Ex d) is a different concept that contains an explosion. The IS-04Z1 is intrinsically safe by design.
Refining units, a heavy-oil upgrading facility, an olefins cracker, aromatics and polypropylene plants together create flammable vapour and gas areas, including ethylene and aromatic hydrocarbons. The operator sets zones and gas groups, so ask for classification drawings before bringing devices.
The city has an industrial port coast and rail and road links to Gwangju and other Korean cities, so delivery is feasible, though customs and approvals take time for imported electronics. Confirm lead times with your forwarder and the site's gate rules.
It may. A restructuring plan involving Lotte Chemical's Yeosu operations was approved, and its status could change. Procurement and HSE contacts may be in transition. Confirm requirements with the site operator before sending any documents.
Other guides for Yeosu, other places in South Korea, and the pages behind them.
Share the site details and quantity. You will get the datasheet and the certification schedule back by email; pricing is indicative only until launch.
Name the site and the operator and we will send what is available before launch.