An offshore contractor once told us his site had installed IP66 cable glands on a subsea junction box — because “IP68 is basically the same, just higher.” Six months later, saltwater ingress shut down the panel. That single digit is not a rounding error. It is the difference between a gland built for driving rain and one built for permanent submersion.
If you’re specifying cable glands for an industrial, offshore, or export project, getting the IP66 vs IP68 cable gland decision right protects both your equipment and your compliance paperwork. This guide by Cabex India breaks down exactly what each rating tests, where each one belongs, and how to avoid over-spending or under-protecting your installation.
What Is the Real Difference Between an IP66 and IP68 Cable Gland?
An IP66 cable gland is built to resist powerful water jets and dust, but not immersion. An IP68 cable gland is built to survive continuous submersion, at a depth and duration the manufacturer defines and tests.
Both ratings come from the same source: IP ratings are based on IEC 60529, the international standard that specifies protective qualities for electrical enclosures and creates the ingress protection rating system widely used across the EU and beyond. Each rating is a two-digit code. The first digit covers solids — dust, tools, fingers. The second covers liquids — from light spray to full immersion.
For a cable gland, that second digit is where IP66 and IP68 part ways completely. IP66 stops at pressurised jets. IP68 stops at ongoing underwater exposure. Confusing the two on a datasheet can mean choosing a gland that fails the moment it goes below the waterline.
How Does the IEC 60529 Standard Actually Test Each Digit?
The IP code is not a marketing label — it is a lab-tested spec with fixed procedures for most levels, and a negotiated procedure for one.
The table below shows what the digits in “IP66” and “IP68” actually mean during testing.
| IP Digit | What It Tests | IP66 Result | IP68 Result |
| First digit (solids) | Dust and particle ingress | 6 — dust-tight, zero ingress | 6 — dust-tight, zero ingress |
| Second digit (liquids) | Water ingress | 6 — protected against powerful water jets from any direction | 8 — protected against continuous immersion beyond IP67 conditions |
| Test method | Lab procedure | Enclosure subjected to 100 litres per minute of water at 100 kPa pressure, from 3 metres, for at least 3 minutes | Depth and duration set jointly by manufacturer and customer, since the standard only requires performance beyond IP67 |
| Governing standard | — | IEC 60529 | IEC 60529 |
Notably, IP68 is not a fixed test the way IP67 is — IEC 60529 only requires that IP68 protection exceed IP67, so the exact immersion depth and duration must be jointly agreed between manufacturer and customer. In practice, this means two products both labelled “IP68” can offer very different real-world protection. Always check the datasheet’s stated depth and duration, not just the two-digit code.
When Should You Choose an IP66 Cable Gland Over IP68?
Choose IP66 when your installation faces heavy weather exposure but never sits underwater. IP66 is the standard specification for most outdoor industrial and plant environments.
For most outdoor electrical enclosures and hazardous-area installations, IP54 is treated as the practical minimum, while IP66 is considered the premium specification for sites that face driving rain, washdown cycles, or dust storms. This covers a large share of Cabex India’s Gulf-facing client base — refineries, substations, and processing plants where cable entries are exposed to weather but not submersion.
Typical IP66 use cases include:
- Outdoor junction boxes on refinery walkways
- Substation cable entries exposed to monsoon-level rainfall
- Desert installations facing sand and dust ingress rather than water
- Washdown areas in food or chemical processing plants
If your enclosure never goes below water, spending extra for a fully IP68-tested gland adds cost without adding usable protection.
Why Do Offshore and Subsea Projects Require IP68 Cable Glands?
Offshore and subsea installations need IP68 because the cable entry point sits in or near water permanently, not occasionally. A gland rated only for jets, not immersion, will eventually let water track along the cable core.
IP68-rated explosion-proof cable glands, tested for continuous submersion at one metre depth for 24 hours, are built for offshore platform cable entries, subsea junction boxes, and coastal installations. This is precisely the profile of many Middle East and North African offshore contracts, where salt spray is constant and tidal cable runs are common.
Furthermore, offshore platforms face constant salt spray, desert rigs face dust and sand, and pipelines in cold regions face moisture and ice — a correctly rated IP66, IP67, or IP68 gland is what blocks each of these threats. Matching the rating to the actual exposure, not the highest number available, is the core of a sound spec.
Does an IP68 Cable Gland Automatically Include IP66 Protection?
No. This is one of the most common misreadings on a datasheet, and it can lead to a costly field failure.
Water protection levels 1 through 6 are cumulative, but levels 7 and 8 are not automatically implied by level 6 — an IP67-rated device has passed the immersion test, but it may not have passed the high-pressure jet test. In other words, a gland tested only for underwater conditions might not have been separately tested against a direct pressurised hose spray during installation or maintenance.
Consequently, procurement teams that need both jet resistance and submersion resistance should look for a dual-rated product explicitly marked IP66/IP68, not assume one rating covers the other. Cabex India’s ATEX-certified cable gland range is tested and documented against both conditions where dual protection is required.
What Materials Work Best for IP66 vs IP68 Cable Glands in Gulf and Coastal Conditions?
Material choice affects how long the IP rating actually holds up in the field — a correctly rated gland in the wrong material can still corrode and fail early.
| Material | Best For | IP Rating Compatibility | Notes |
| Nickel-plated brass | General industrial, refineries | IP66–IP68 | Offers excellent corrosion resistance, good conductivity, and cost efficiency |
| Stainless steel SS316/SS316L | Offshore, marine, subsea | IP66–IP68 | Recommended for all marine and offshore environments for maximum chloride and saltwater resistance over the installation’s service life |
| Aluminium alloy | Weight-sensitive offshore structures | IP66–IP68 | Lightweight yet strong, with natural corrosion resistance and non-magnetic properties, well suited to offshore and marine installations |
| Polyamide (non-metallic) | Chemical-exposed, intrinsically safe systems | Typically IP66–IP67 | Chosen for chemical resistance rather than mechanical strength |
For Gulf coastal and offshore projects specifically, SS316L is the safer long-term choice even where brass would technically pass the IP test on day one. Salt exposure degrades plated brass faster than it degrades the seal itself.
How Do ATEX and IECEx Certification Requirements Interact with IP Ratings?
ATEX and IECEx certification and IP ratings are separate requirements that must both be satisfied — one does not substitute for the other.
ATEX cable glands used in oil and gas, chemical, mining, and marine environments typically carry an IP66 to IP68 rating for water and dust protection, alongside separate ATEX and IECEx certification for hazardous-area use. A gland can be perfectly explosion-rated for Zone 1 and still fail on ingress protection if the IP rating doesn’t match the site’s water exposure — and vice versa.
Additionally, double compression glands, which use two independent sealing elements to grip and seal both the cable’s inner armour layer and its outer sheath, are the standard choice for armoured cables and typically achieve the higher IP68 performance level. If your project spec calls for armoured cable in a submerged or buried run, a single-compression gland — even at IP66 — will not meet the requirement.
IP66 vs IP68 Cable Gland: What’s the Cost Difference?
IP68 glands generally cost more than IP66 glands because of the additional sealing elements, tighter tolerances, and extended testing needed to certify submersion performance. We were not able to verify a consistent, currently published price differential across manufacturers for this comparison — pricing varies by thread size, material, and certification body, so treat any percentage figure you see elsewhere as against your supplier’s quotation rather than a fixed industry number.
The more useful comparison for procurement is total cost of ownership: an under-specified IP66 gland installed in a submerged application will likely need early replacement, plus the cost of any downtime or water damage it causes. Matching the rating to the actual exposure the first time is usually cheaper than upgrading after a failure.
IP66 vs IP68 Cable Gland: Quick Decision Matrix
| Your Installation Condition | Recommended Rating |
| Outdoor, rain and dust exposure, no standing water | IP66 |
| Washdown or high-pressure cleaning cycles | IP66 |
| Occasional shallow puddling, brief immersion risk | IP67 |
| Continuous or long-term submersion (subsea, tidal, underground) | IP68 |
| Offshore platform, coastal salt spray with occasional wave contact | IP66/IP68 dual-rated |
| Armoured cable in a buried or submerged run | IP68, double compression |
Ready to Specify the Right Cable Gland for Your Project?
Choosing between IP66 and IP68 shouldn’t come down to guesswork on a datasheet. Cabex India’s engineering team can review your site conditions, cable type, and hazardous-area classification, then recommend the exact gland — material, thread type, and IP rating — that matches your project spec and export documentation requirements. Get in touch with Cabex India for a technical consultation before you finalise your BOM.
Conclusion
IP66 and IP68 solve two different problems, not two points on the same scale. IP66 handles pressurised water and dust in exposed, non-submerged environments. Manufacturers, on the other hand, build IP68 specifically for continuous immersion, and each one defines the exact depth and duration they test. Therefore, always check the datasheet, match the rating to your actual site exposure, and confirm ATEX or IECEx certification separately where hazardous areas are involved.
IP66 vs IP68 Cable Gland: Frequently Asked Questions
Is IP68 always better than IP66?
No — IP68 handles submersion better, but it doesn’t guarantee the same high-pressure jet resistance that IP66 specifically delivers. So the better rating depends on your exposure type.
Can an IP66 cable gland be used underwater?
No — IP66 is tested against water jets, not immersion, and using it underwater risks water tracking along the cable core over time.
What does IP68 actually guarantee, since the depth varies by manufacturer?
IP68 guarantees performance beyond the IP67 immersion test, with the specific depth and duration set and documented by the manufacturer for that product.
Do ATEX-certified cable glands automatically include an IP68 rating?
No — ATEX and IECEx certify explosion protection for hazardous areas. The IP rating is a separate spec, however, and you must confirm it independently on the datasheet.
What IP rating is standard for offshore oil and gas cable glands?
Offshore and subsea cable entries typically require IP68, often alongside SS316L construction and ATEX or IECEx certification for the relevant hazardous zone.
