IP Rating Chart & Guide: Waterproof & Dustproof Standards for Linear Actuators
When selecting electrical and mechanical components such as linear actuators, understanding their IP rating is essential to ensure long-term reliability in real-world environments. Improperly specified ingress protection can result in premature failure, corrosion, or costly downtime.
This guide explains how IP ratings work, how to interpret them correctly, and how to select the appropriate protection level for your specific application.
What Does IP Rating Mean? (Ingress Protection Explained)
An IP rating (Ingress Protection rating) is a standardized two-digit classification that defines how effectively an enclosure prevents the intrusion of solid particles and liquids. Under-specifying an IP rating can expose internal components, such as DC motors, bearings, and control electronics, to moisture or dust contamination, leading to reduced lifespan or irreversible damage. An example of this includes water intrusion into an actuator that reaches the limit switches, causing a short circuit.
IP Rating Chart: How to Read Waterproof & Dust Protection Codes
The IP classification chart visually breaks down how each digit corresponds to specific protection levels, making comparison between enclosures straightforward.
Start by reading the first digit on the left to determine the level of dust/solid protection. Next, read the second digit on the right to determine the protection against water/liquid ingress. The higher the value of each digit, the greater the protection level of its respective purpose.
While charts provide quick reference, understanding how these ratings translate into real operating conditions is critical - especially for outdoor, industrial, marine, or washdown applications.
Understanding the IP Rating System (IEC 60529 Standard)
The IP rating system follows the internationally recognized IEC 60529 standard, developed by the International Electrotechnical Commission (IEC). It defines a structured testing methodology to evaluate enclosure resistance to solid particle ingress and liquid exposure.
Testing is conducted under controlled laboratory conditions with defined water pressures, spray angles, immersion depths, and durations.
Our actuator quality has been audited by Perry Johnson Registrars (PJR), which is an accredited registrar for ISO 9001 QMS.
The first digit represents protection against solids, while the second digit defines protection against liquids. Together, they determine the overall ingress protection classification of the enclosure.
IP Rating Numbers Explained: First & Second Digit Meanings
The IP rating system uses a 2-digit system to define its protection rating for all products. The first digit represents protection against solids, and the second against liquids. The IP classification system was designed to standardize protection ratings and limit misinterpretation/misrepresentation of a product's protection ability.
First Digit: Solid Particle & Dust Protection (0–6 Scale)
The first digit represents protection against solid objects such as dust, tools, or accidental contact and can have a value from 0 to 6. It reflects IP grades related to physical intrusion and determines the ingress protection level to withstand foreign objects and dust ingress.
For example, a product that has a rating of IP2X can withstand foreign objects up to 12.5mm or greater in size, whereas an object with a rating of IP6X is dust-tight. "X" is used to designate a specific area where the product has not been tested.
Protection Levels:
- 0: No protection
- 1: Protected against solid objects larger than 50mm
- 2: Protected against solid objects larger than 12.5mm
- 3: Protected against solid objects larger than 2.5mm
- 4: Protected against solid objects larger than 1mm
- 5: Dust protected (limited ingress permitted)
- 6: Dust-tight (complete protection against dust)
The pulp and paper industry may find IP5X ratings to allow limited fine dust ingress over time, potentially affecting lead screw lubrication or the smooth operation of internal gears.
Second Digit: Water & Liquid Protection Levels (0–9 Scale)
The liquid protection (second digit) follows the same format but can have a value from 0 to 9. As the number increases, protection from liquid ingress increases. Units with an IPX7 rating have a waterproof IP rating against 30-minute submersions at a depth of 1 meter.
As the chart indicates, there are specific angles, pressures, and volume requirements that must be followed during the test for water spray protection. The stringent testing procedure of the IP rating system ensures standardization between testing facilities around the world.
Protection Levels:
- 0: No protection
- 1: Protected against vertically dripping water
- 2: Protected against dripping water at 15° angle
- 3: Protected against spraying water at 60° angle
- 4: Protected against splashing water from all directions
- 5: Protected against low-pressure water jets from any direction
- 6: Protected against high-pressure water jets
- 7: Protected against temporary water immersion (1m depth, 30 minutes)
- 8: Protected against continuous immersion under pressure
- 9K: Protected against high-pressure, high-temperature water jets
It is important to note that jet pressure exposure (IP66) and immersion depth (IP67/68) represent different water ingress stress mechanisms. A higher IP number does not automatically mean broader or stronger protection across all conditions.
Important disclaimer: An IP rating does not indicate permanent waterproofing. IP ratings are based on controlled test conditions and do not guarantee unlimited exposure.
Environmental factors such as UV rays, fluctuations in temperature/humidity, salt exposure, dust/dirt ingress, and pressure changes need to be considered. These factors may accelerate seal degradation and/or cause gasket compression fatigue from repeated exposure.
What Does "X" Mean in an IP Rating?
An IP rating uses "X" when one of the protection categories has not been tested. For example, IPX4 means the product has been tested for liquid exposure but not solid particle protection. An IP rating of IP6X means the product has been tested for dust protection but not against exposure to liquids.
Supplementary Letters in IP Ratings
Sometimes, an IP rating may have a letter placed at the end of the last digit. This is the supplementary letter, and it can be used to denote supplementary information from the product standard:
- A: Protected against access with back of hand
- B: Protected against access with finger
- C: Protected against access with tool
- D: Protected against access with wire
- H: High voltage apparatus
- M: Device moving during water test
- S: Device stationary during water test
- W: Weather conditions
Common Waterproof IP Ratings: IP65, IP66, IP67 & IP68 Comparison
Understanding common waterproof IP ratings helps you select the right protection level for your waterproof linear actuators and other equipment.
IP65: Low-Pressure Water Jet Protection
IP65 provides complete dust protection and resistance to low-pressure water jets from any direction. This rating is suitable for most outdoor applications where equipment may be exposed to rain or occasional water spray but not high-pressure washing.
Applications: Outdoor lighting, covered industrial equipment, general outdoor automation
IP66: High-Pressure Water Jet Resistance
IP66 offers the same dust-tight protection as IP65 but adds resistance to powerful high-pressure water jets. The test includes the enclosure being subjected to 100 liters per minute of water at a pressure of 100 kPa from a distance of 3 meters for at least 3 minutes.
Applications: Industrial washdown environments, agricultural equipment, construction sites
Actuators, while in the retracting motion under high-pressure spray, may pull water into the shaft housing if the unit has an O-ring that was only rated for static water resistance.
IP67: Temporary Water Submersion Rating (1 Meter, 30 Minutes)
IP67 rating provides complete dust protection and allows for temporary submersion in water up to 1 meter deep for a maximum of 30 minutes. This makes it ideal for equipment that may occasionally be exposed to brief immersion.
When there is no "M" marking after the second digit, the IP67 protection is only tested for stationary conditions.
Applications: Marine equipment, outdoor sensors, temporary underwater use
IP68: Extended Submersion Protection for Underwater Use
IP68 provides the highest level of standard protection, allowing for continuous immersion in water beyond 1 meter depth. The exact depth and duration are specified by the manufacturer, as IP68 is not a fixed standard but rather indicates "better than IP67."
Unlike IP67, which defines immersion up to 1 meter for 30 minutes, IP68 must exceed those minimum requirements, but the actual test conditions (depth and time) vary by manufacturer. One IP68 product may be rated for 1.5 meters, while another may withstand several meters of depth for extended periods. Always verify the manufacturer's specified test parameters rather than assuming all IP68 ratings provide identical protection.
Applications: Permanent underwater equipment, submersible pumps, deep marine applications
IP67 vs IP68: What's the Difference for Waterproof Protection?
When comparing IP67 vs IP68 waterproof ratings, understanding the specific differences is crucial for selecting the right protection level for your marine linear actuators and underwater applications.
Submersion Depth & Duration Differences
IP67 Protection:
- Depth: Up to 1 meter
- Duration: Maximum 30 minutes
- Testing: Standardized conditions (1 meter depth for 30 minutes)
- Application: Temporary immersion, accidental submersion
IP68 Protection:
- Depth: Greater than 1 meter (manufacturer-specified)
- Duration: Longer than 30 minutes (manufacturer-specified)
- Testing: Varies by manufacturer (must exceed IP67 requirements)
- Application: Continuous or prolonged submersion
Critical Understanding: IP68 is not a fixed standard. One manufacturer may rate their device IP68 for 1.5 meters for 30 minutes, while another may rate theirs IP68 for 3 meters for 2 hours. Always check the manufacturer's specific IP68 specifications.
When to Choose IP67 for Linear Actuators
IP67 is the right choice when:
- Equipment may face accidental water exposure or brief submersion
- Applications involve rain, splashes, or temporary flooding
- Cost is a consideration (IP67 is typically less expensive than IP68)
- Submersion deeper than 1 meter is unlikely
- Standard outdoor or marine applications with occasional water contact
An IP65 actuator for opening fence gates, while suitable in the rain, does not have sufficient water protection against flooding conditions that submerge the unit and allow water ingress into the motor housing.
Progressive Automations IP67M Products: The PA-06 Waterproof Electric Linear Actuator and PA-ST4 Compact Tubular Actuator feature IP67M ratings, meaning they are tested while in motion and can operate during short submersion periods.
The "M" designation is critical for actuators with dynamic seals because it confirms the ingress protection test was performed while the shaft was moving, ensuring the sealing system maintains protection under motion rather than only when stationary.
When IP68 Protection Is Necessary
Choose IP68 when:
- Equipment will be permanently installed underwater
- Applications require submersion deeper than 1 meter
- Prolonged water exposure (hours or continuous) is expected
- Maximum protection is required regardless of cost
- Harsh marine environments with deep water operation
Comparison Between IP67 and IP68
Both IP67 and IP68 provide complete dust protection. The key difference lies in water submersion capabilities. For most outdoor automation applications, including marine, agricultural, and industrial uses, IP67 provides sufficient protection. The IP68 rating should be reserved for applications requiring guaranteed deep or continuous submersion.
Multiple IP Ratings on One Product
Some products display multiple ratings (e.g., IP55/IP57). This indicates the enclosure passed certain protection levels but did not meet intermediate test criteria.
For example, a device may pass IPX7 immersion testing but not IPX6 high-pressure jet testing.
It is important to clarify that IPX7 does NOT automatically imply compliance with IPX6. These tests evaluate different stress mechanisms: IPX6 measures resistance to powerful water jets, while IPX7 evaluates temporary immersion under static water pressure. Because the exposure conditions differ significantly, passing one test does not guarantee passing the other.
Water Resistance vs Waterproof: Understanding IP Rating Protection
Water-resistant classifications (IP54–IP65) protect against spray and jets but do not permit submersion. Waterproof classifications (IP67–IP68) allow immersion under defined test conditions.
It's important to clarify that "waterproof" is often used as a marketing term, while IP ratings provide standardized, test-based verification of protection levels. Always refer to the specific IP code rather than relying solely on the word "waterproof."
It is also important to note that IP ratings do not evaluate long-term UV degradation, thermal cycling, chemical exposure, or multi-season outdoor weathering.
Important Note for Linear Actuator Operation
All Progressive Automations linear actuators are designed and tested primarily for stationary ingress protection unless marked otherwise.
When an actuator moves, the extension and retraction of the shaft can create dynamic pressure changes at the seal interface. This can allow moisture to migrate into the housing if the device is not rated for motion during exposure.
Why Motion Changes Everything
Dynamic Seal Exposure
Linear actuators rely on shaft seals to prevent ingress. During movement, these seals experience friction, deformation, and pressure differentials. Unlike static testing, dynamic operation can momentarily reduce sealing effectiveness, especially under spray or immersion conditions.
Water Wicking Into the Housing
When the actuator shaft retracts, surface moisture can be drawn inward along the shaft through capillary action, a phenomenon known as wicking. Over time, repeated cycles increase the likelihood of moisture reaching internal components.
Motor Winding Corrosion
If water enters the housing, copper motor windings may begin to oxidize. Corrosion increases electrical resistance, reduces efficiency, and can eventually cause overheating or winding failure.
Bearing Oxidation
Internal bearings and gears are typically lubricated. Water contamination degrades lubrication and promotes oxidation, leading to premature wear, increased friction, and mechanical noise.
Irreversible Electrical Shorting
Moisture inside the motor or limit switch assembly can create unintended conductive paths. This may result in short circuits, erratic operation, or permanent electrical failure.
For these reasons, it is important not to operate actuators while wet unless specifically rated for dynamic exposure (e.g., IP67M).
Real-World Failures: What Happens When the Wrong IP Rating Is Selected
Selecting an inadequate IP rating can lead to costly failures and system downtime. Below are real-world examples of what can occur when environmental conditions exceed rating limits:
1. IP65 Actuator Used in a Washdown Environment
An actuator rated for dust-tight and water jet resistance (IP65) was installed in a high-pressure washdown setting. Continuous exposure to directional jets forced water past shaft seals, resulting in internal motor corrosion and early failure.
Result: Equipment downtime, actuator replacement, and lost production hours.
2. Repeated IP67 Immersion Beyond Rated Duration
An actuator rated for temporary immersion (1 meter for 30 minutes) was repeatedly submerged for extended periods. Over time, gasket compression fatigue reduced sealing performance, allowing gradual ingress.
Result: Accumulated moisture damage, increased maintenance costs, and unexpected system shutdown.
3. Salt Spray Marine Exposure
An actuator rated for freshwater immersion was installed in a coastal marine environment. Although the IP rating was met, salt spray accelerated internal oxidation of fasteners and motor components.
Result: Premature corrosion, structural weakening, and costly replacement.
Understanding environmental exposure in real-world conditions is just as important as reading the IP code itself. These examples illustrate that IP ratings define laboratory-tested conditions, not unlimited environmental protection. Selecting the correct ingress protection level helps reduce downtime risk, replacement costs, and system reliability failures.
IP Rating Recommendations by Application Environment
Different environments require different IP protection standards. Using an IP protection rating chart as a reference can help guide users in their selection process:
Indoor Automation
Recommended Rating: IP20 to IP44
- Controlled environment with minimal dust
- No water exposure expected
- Examples: Adjustable desks, TV lifts, indoor furniture
- Progressive Automations Product: PA-18 Track Linear Actuator (IP20)
Outdoor Use (Covered)
Recommended Rating: IP54 to IP65
- Protection from rain and dust
- Limited direct water exposure
- Examples: Covered patios, protected equipment, outdoor signage
- Progressive Automations Product: PA-04 Standard Actuator (IP65)
Outdoor Use (Exposed)
Recommended Rating: IP65 to IP66
- Direct exposure to rain and weather
- High-pressure washing may occur
- Examples: Agricultural equipment, construction machinery, outdoor industrial
- Progressive Automations Products: PA-09 Mini Industrial Actuator (IP66), PA-10 Waterproof Actuator (IP66)
Marine & Underwater Applications
Recommended Rating: IP67 to IP68
- Temporary or permanent water submersion
- Salt spray and corrosive environments
- Examples: Boat hatches, underwater sensors, marine automation
- Progressive Automations Products: PA-06 IP67M, PA-ST4 IP67M
Washdown Environments
Recommended Rating: IP66 to IP69K
- High-pressure, high-temperature cleaning
- Food processing, medical, pharmaceutical
- Examples: Clean rooms, food production, hospitals
- Requirement: IP66 minimum, IP69K for intensive washdown
Harsh Industrial Environments
Recommended Rating: IP66 to IP67
- Heavy dust, debris, and moisture
- Chemical exposure possible
- Examples: Mining, manufacturing, chemical processing
- Progressive Automations Product: Industrial Actuators (IP66)
How Progressive Automations Products Are Tested
All Progressive Automations' linear actuators are tested under the Ingress Protection standards by IEC (International Electrotechnical Commission). Our control systems and wiring are also designed to work seamlessly with IP-rated actuators. Our linear actuators range from IP20 all the way up to IP67M.
IP20 Indoor Actuators: PA-18 Track Actuator
The PA-18 Track Linear Actuator has a rating of IP20, as it has open shaft housings, which would allow water to enter the unit. This illustrates when a unit can hold against foreign objects but has zero protection against liquid.
IP66 Industrial Actuators: PA-09 & PA-10 Series
Units rated for IP66, like the PA-09 Mini Industrial Actuator and PA-10 Waterproof Actuator, are able to withstand both dust and liquid ingress. The PA-10 is also available in a Salt Spray rated version with specialized porcelain plated housing, tested for up to 400 hours of salt spray exposure for harsh marine environments.
IP67M Waterproof Actuators: PA-06 & PA-ST4 Models
The PA-06 and PA-ST4 waterproof tubular actuators have the highest IP rating in our range, with IP67M. They both can operate underwater for 30-minute submersions at a depth of 1 meter and are able to withstand high-pressure water jets when they're not in motion.
The "M" designation is critical, it means these actuators were tested while moving, not just stationary. This provides real-world protection during actual operation, making them ideal for marine and agricultural applications.
IP Rating Comparison Table: Quick Reference Guide
| IP Rating | Dust Protection | Water Protection | Best For | PA Product Examples |
|---|---|---|---|---|
| IP20 | Limited (>12.5mm objects) | None | Indoor, clean environments | PA-18 |
| IP54 | Dust protected | Splash resistant | Light outdoor, covered areas | PA-12-T |
| IP65 | Dust-tight | Low-pressure jets | Outdoor, general industrial | PA-01 |
| IP66 | Dust-tight | High-pressure jets | Heavy industrial, washdown | PA-09, PA-10 |
| IP67 | Dust-tight | Temporary submersion (1m, 30min) | Marine, temporary underwater | PA-HD3 |
| IP67M | Dust-tight | Submersion while moving | Marine, active underwater use | PA-06, PA-ST4 |
| IP68 | Dust-tight | Continuous submersion (manufacturer-specified) | Permanent underwater | - |
| IP69K | Dust-tight | High-pressure, high-temp jets | Food processing, intensive washdown | - |
Choosing the Right IP Rating for Your Application
When selecting linear actuators or other electrical components, consider:
- Environmental Exposure: Indoor vs outdoor, dust levels, water contact frequency
- Water Exposure Type: Dripping, splashing, jets, or submersion
- Duration of Exposure: Temporary vs continuous exposure
- Operational Requirements: Will the device operate while wet?
- Cost Considerations: Higher IP ratings require more complex seals and construction
- Regulatory Requirements: Some industries mandate specific IP ratings
- Maintenance Access: Higher ratings may be harder to service
Cost vs Protection Balance
While higher IP ratings provide better protection, they also increase cost due to:
- More complex sealing systems
- Specialized materials and coatings
- Additional testing and certification
- Potentially reduced performance (added seals increase friction)
Choose the lowest IP rating that meets your application requirements to optimize cost without compromising protection.
Installation and Mounting Considerations
When installing IP-rated linear actuators, proper mounting brackets for waterproof applications are essential. Even the highest IP rating can be compromised by improper installation.
Best Practices:
- Ensure mounting points don't create water pooling areas
- Use appropriate gaskets and sealants at connection points
- Route cables to prevent water ingress at electrical connections
- Consider ventilation requirements (breathing holes may reduce IP rating)
- Verify actuator orientation doesn't expose vulnerable areas
For custom IP-rated actuator solutions, our engineering team can help specify the right protection level and mounting configuration for your specific application.
Frequently Asked Questions (FAQ)
What does an IP rating mean?
An IP (Ingress Protection) rating describes how well an enclosure resists the intrusion of solids and liquids. The two-digit code indicates protection levels for dust (first digit) and water (second digit).
Is an IP rating the same as waterproof?
No, only certain waterproof IP ratings can offer true waterproof protection for an extended duration, depending on the value of the second digit of a given IP rating. Terms like "waterproof" are vague, while IP ratings provide specific, testable protection levels.
What does IP65 mean for linear actuators?
An IP65 protection rating indicates dust-tight construction and resistance to low-pressure water jets from any direction, making it suitable for most outdoor automation applications where equipment is exposed to rain and dust.
What is the difference between IP67 and IP68?
The IP67 vs IP68 distinction lies primarily in water immersion capabilities. IP67 allows temporary submersion up to 1 meter for 30 minutes under standardized conditions. IP68 allows deeper and/or longer submersion, but the exact specifications are determined by the manufacturer. Always check specific IP68 ratings as they vary significantly between products.
Can an IP-rated actuator be used outdoors year-round?
It depends on the IP protection level and additional environmental factors. An IP66 or IP67 rated actuator can generally handle year-round outdoor use, but factors like UV exposure, temperature extremes, corrosive materials, and seasonal changes should be considered. IP ratings test water and dust protection but not long-term weather degradation.
Does an IP rating apply when the actuator is in motion?
For an IP rating to apply when the actuator is in motion, there must be the letter "M" included in the rating to indicate that it has passed test conditions with the device in motion. Standard IP ratings are tested with stationary devices. The Progressive Automations PA-06 and PA-ST4 models feature IP67M ratings, providing protection during operation.
What IP rating is recommended for washdown environments?
Typically, an IP rating of IP66 or higher is recommended for washdown environments where high-pressure water jets are used. For food processing or pharmaceutical applications with high-temperature, high-pressure cleaning, IP69K is the appropriate choice.
Why do some products have multiple IP ratings?
Some products list multiple IP ratings (like IP55/IP57) because they passed different protection tests at different levels. This indicates the device didn't pass a middle level (IPX6 in this example) but did pass higher level tests. Always reference the specific test conditions for accurate protection understanding.
What's the difference between water-resistant and waterproof IP ratings?
Water-resistant ratings (IP54–IP65) protect against water spray, splashing, or jets but not submersion. Waterproof IP ratings (IP67–IP68) allow for temporary or continuous submersion in water. The distinction is critical for selecting appropriate equipment for your environment.
How do I maintain IP-rated equipment?
Regular inspection of seals and gaskets is essential. Check for cracks, wear, or compression damage. Clean according to manufacturer specifications, some cleaning methods can degrade seals. Replace any damaged sealing components immediately. Avoid operating wet equipment unless rated IP67M or higher.
Can I upgrade an actuator's IP rating after purchase?
Generally, no. IP ratings are determined by the design and construction of the enclosure. However, you can install the actuator within a separate IP-rated enclosure to achieve higher protection levels for the overall system. Contact our engineering team for custom enclosure solutions.
What does IP69K mean and when is it used?
IP69K is the highest IP rating, designed for high-pressure (80–100 bar), high-temperature (80°C) cleaning applications. It's commonly used in food processing, pharmaceutical manufacturing, and heavy equipment that requires intensive washdown. The "K" designation comes from the German DIN 40050-9 standard.
Are IP ratings the same as NEMA ratings?
No. IP ratings (international standard IEC 60529) and NEMA ratings (North American standard) use different testing methods. While there are approximate equivalencies (IP65 ≈ NEMA 4), they're not directly interchangeable. IP ratings focus specifically on ingress protection, while NEMA ratings include additional criteria like corrosion resistance and construction requirements.
How often should IP ratings be re-tested?
IP ratings don't expire, but the physical protection can degrade over time. For critical applications, annual inspection of seals and periodic re-testing is recommended. Any maintenance that requires opening the enclosure may compromise the IP rating until properly resealed.
Summary: Choosing the Right IP Rating for Your Linear Actuator
IP ratings provide standardized, test-based measurements for dust and water protection. Selecting the appropriate rating requires evaluating real environmental exposure, not simply choosing the highest number available.
Key Takeaways:
- First digit (0 to 6): solid particle protection
- Second digit (0 to 9): liquid protection
- Higher ratings increase cost and sealing complexity
- Dynamic operation requires motion-rated protection (e.g., IP67M)
- Avoid over-specifying beyond actual environmental needs