History
Oil was discovered in the Williston Basin in 1951. Horizontal drilling and hydraulic fracturing lifted output, and North Dakota and Montana together passed 1 million barrels a day in April 2014.
The Bakken is a shale oil formation in the Williston Basin of western North Dakota, centred on towns such as Williston and Watford City. Zone 1 work arises at drilling rigs, wellsites, tank batteries and gas gathering facilities. If you are specifying an intrinsically safe mobile phone for Bakken, North Dakota (Williston Basin), 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 Bakken, North Dakota (Williston Basin): pre-launch, designed for Zone 1 and Zone 21 (marking target Ex ib IIC T4), with certification in progress and no certificate issued.
For the record, no certificate exists for the IS-04Z1 today. The programme is under way ahead of a Q4 2026 launch. Operator approval runs on its own timeline. 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 | Bakken, North Dakota (Williston Basin): Drilling rigs, Wellsites and tank batteries, Gas gathering and processing | Classified by the site operator |

An intrinsically safe Android smartphone designed for Zone 1 and Zone 21 hazardous areas in North Dakota Bakken. It is pre-launch: IECEx, ATEX and NEC 500 certification is in progress ahead of the Q4 2026 launch.
Who operates there and which kinds of classified area a handset would meet, from the SAMS site research.
Oil was discovered in the Williston Basin in 1951. Horizontal drilling and hydraulic fracturing lifted output, and North Dakota and Montana together passed 1 million barrels a day in April 2014.
Operators listed for the Bakken include Continental Resources, Chord Energy, EOG Resources and Hess. Chevron completed its purchase of Hess on 18 July 2025.
The city sits at the crossroads of US Highways 2 and 85, near the Missouri and Yellowstone rivers, about 18 miles from Montana and 60 miles from the Canadian border.
Satellite land-cover data show about 46 square kilometres of developed land around Williston in 2024, showing how energy development left a lasting footprint on a rural town.
Williston sits close to the centre of the Williston Basin, directly above the Bakken Formation, which is among the largest oil fields in the United States.
The Bakken is relatively thin, no more than 250 feet, with low permeability, so better knowledge of where the resource lies has translated directly into higher output.
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 Bakken, North Dakota (Williston Basin). Technicians in western North Dakota travel to remote wellsites and tank batteries for gauging, checks and records. A handheld intrinsically safe phone is designed to be carried into those Zone 1 areas. Cold weather affects batteries, so low-temperature handling matters, and certification must be finished before use in classified areas.
A short checklist for anyone writing or reviewing the specification, with the IS-04Z1 status against each point.
Not yet. The IS-04Z1 is pre-launch and its certification is still in progress ahead of a Q4 2026 launch. No unit goes into a classified area before the certificate covering it exists. The datasheet, the certification schedule and safe-area evaluation units are available now.
There is no list price yet. SAMS gives indicative pre-launch pricing in writing, against a stated quantity and site, and does not commit to a lead time before certification completes.
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 drilling rigs, wellsites and tank batteries, gas gathering and processing, crude loading facilities. 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.
Wellpads and associated tank and compressor areas can contain flammable gas and vapour, and the operator defines classified areas and approvals. Always ask for the site's area classification and equipment policy before entering.
Williston records a January mean around 11.5 degrees Fahrenheit and several days a year at minus 20 or lower. Check a handset's low-temperature operating range and battery performance in the cold, and keep spare batteries warm inside clothing.
The Bakken is remote with cold winters, so low-temperature performance and battery life are practical concerns for portable equipment. Check the datasheet's operating range once published, keep spare charged devices in a safe, warm area, and trial the phone in your own conditions. Confirm limits with the site operator.
Other guides for North Dakota Bakken, other places in United States, and the pages behind them.
Tell us what you need to equip and where. The SAMS team answers by email with the datasheet and where each certification route stands.
Name the site and the operator and we will send what is available before launch.