What Is an IP Rating? Quick Definition
An IP (Ingress Protection) rating is a two-digit code defined by IEC 60529 that rates how well an enclosure or connector housing keeps out solid objects and liquids. The first digit covers solid particles and physical contact; the second covers water. A higher digit means more protection, but the two digits are independent — a connector can be excellent against dust and mediocre against water, or vice versa. "IP67" is shorthand for "first digit 6, second digit 7," not a single combined score.
Source: International Electrotechnical Commission — IEC 60529, Degrees of protection provided by enclosures (IP Code). This page is a quick-reference summary; the current official standard is the authority, not this chart.
First Digit: Solid Particle & Contact Protection (0–6)
- 0: No protection against contact or solid object ingress.
- 1: Protected against large body surfaces (hand) and solid objects larger than 50mm.
- 2: Protected against fingers and solid objects larger than 12.5mm.
- 3: Protected against tools and wires larger than 2.5mm.
- 4: Protected against most wires and solid objects larger than 1mm.
- 5: Dust-protected — dust may enter, but not in a quantity that interferes with safe operation.
- 6: Dust-tight — no ingress of dust at all, with full contact protection.
Second Digit: Liquid Ingress Protection (0–9)
- 0: No protection against water.
- 1: Protected against vertically dripping water.
- 2: Protected against dripping water when tilted up to 15°.
- 3: Protected against water sprayed at an angle up to 60° from vertical.
- 4: Protected against splashing water from any direction.
- 5: Protected against low-pressure water jets from any direction.
- 6: Protected against powerful water jets and brief flooding from any direction.
- 7: Protected against temporary immersion — typically 1 meter depth for 30 minutes.
- 8: Protected against continuous immersion — the specific depth and duration are set by the manufacturer, not a fixed standard value, so always check the datasheet rather than assuming "IP68 means waterproof at any depth."
- 9: Protected against high-pressure, high-temperature water jets at close range — the same hazard IP69K addresses (see below); IEC 60529 added this level after IP69K was already established elsewhere.
A Note on IP69K: It's Not Officially Part of IEC 60529
IP69K shows up constantly on connector datasheets, but it did not originate in IEC 60529 — it comes from DIN 40050-9, a German automotive standard, and was later carried into ISO 20653 (Road vehicles — Degrees of protection). The "K" specifically denotes the high-pressure, high-temperature wash-down test: water at roughly 80°C sprayed at 80-100 bar from four angles at close range (10-15cm), cycling every 30 seconds. IEC 60529 itself has since added its own level-9 second digit using essentially the same spray test, but "IP69K" as a label is still more accurately described as an ISO 20653 / automotive-industry rating than a pure IEC 60529 one.
Common Combinations on Connector Datasheets
- IP65: Dust-tight, protected against low-pressure water jets. A common baseline for outdoor equipment that sees rain and spray but not submersion.
- IP66: Dust-tight, protected against powerful water jets and brief flooding. One step up from IP65 — common on outdoor industrial and marine-adjacent equipment.
- IP67: Dust-tight, protected against temporary immersion (typically 1m / 30 minutes). Common on handheld and portable equipment that might get briefly dropped in water, not left submerged.
- IP68: Dust-tight, protected against continuous immersion at a depth and duration the manufacturer specifies. Used for genuinely submersible equipment — sump pumps, underwater lighting, marine sensors — but always check the manufacturer's actual depth/duration figures rather than assuming a fixed meaning.
- IP69K: Dust-tight, protected against high-pressure hot-water wash-down. Not a "better IP68" — it tests a completely different hazard (dynamic jet force and thermal shock, not static underwater pressure). A connector rated for deep water can still fail a steam-jet wash-down test, and vice versa. Standard requirement in food/beverage processing, pharmaceutical manufacturing, and vehicles that get pressure-washed daily (cement mixers, dump trucks).
Connector-Specific Checklist
- Read both digits separately: don't assume a high second digit implies a high first digit or vice versa — confirm both are rated, not just the one most prominently advertised.
- For IP68, get the actual depth/duration figures: IP68 alone only means "continuous immersion" — the manufacturer sets the specific depth and time, so a datasheet that says "IP68" without a number is incomplete for anything beyond a shallow, brief application.
- Don't substitute IP68 for IP69K or vice versa: if the application involves pressure washing or steam cleaning, confirm an actual IP69K (or ISO 20653 equivalent) rating — IP68 submersion testing doesn't validate jet/thermal-shock resistance.
- Check mated vs. unmated rating: many connector IP ratings only apply when fully mated with the cap or mating half installed — confirm whether an exposed, unmated connector carries any rating at all.
- Confirm the rating is on the connector itself, not just the enclosure: a sealed enclosure with an unsealed cable gland or connector pass-through can fail at that interface even if the enclosure body is well rated.
How Do I Select the Right IP Rating?
Start with the actual environmental hazard, not a target number — outdoor rain and splash exposure calls for IP65/66, brief accidental submersion calls for IP67, genuine underwater operation calls for IP68 with specific depth/duration figures confirmed, and routine pressure-washing or steam cleaning calls for IP69K specifically, not a higher IP68 number.
Then check the rating applies to the actual connector interface in its mated state, and that any required cable glands, backshells, or mating caps are included in that rating rather than tested separately. For automotive, food/beverage, or pharmaceutical applications, check whether the relevant industry standard (ISO 20653, 3-A Sanitary Standards, etc.) requires a specific test beyond the general IEC 60529 digits.
Where to Go Deeper
This page is a quick-reference chart — for full technical depth on IP ratings in real sealing designs, see Environmental Sealing and IP Ratings for External ADAS Sensors and LiDAR and Radar Sensor Connectors: IP Rating and Signal Integrity. For other standards in this section, see the OCP/ORV3 Compliance Requirements Checklist, the RoHS & REACH Compliance Guide, the UL 94 Flammability Rating Guide, and the MIL-DTL-38999 Connector Series Guide.
Disclaimer
General guidance only. This page is an informational quick-reference summary of IEC 60529 and related IP-rating conventions as they generally apply to connectors — it is not a substitute for reviewing the current official IEC 60529 standard, or ISO 20653 for automotive-specific ratings, directly.
Not affiliated. connectorselection.com is not affiliated with, endorsed by, or acting on behalf of the International Electrotechnical Commission (IEC) or the International Organization for Standardization (ISO).
Not a substitute for verification. IP68 depth/duration figures are manufacturer-specific, not fixed by the standard, and IP69K testing is distinct from IP68 testing. Always verify the specific test conditions and figures behind any IP rating directly with the manufacturer before making a sourcing, design, or safety-compliance decision.