Choose IPX5 or IPX6 from the cleaning exposure, not the pressure printed on the washer. IPX6 addresses a more demanding standardized water-jet test, but neither designation alone establishes suitability for hot, close-range pressure washing. If your specification requires water protection level 6, do not replace it with level 5 because the dust rating improves. First define the nozzle, flow, distance, temperature and chemicals; then select the complete enclosure assembly.
Describe the cleaning exposure first
Record how water actually reaches the enclosure. A distant rinse, a concentrated hose stream and a rotating pressure-washer jet create different exposures. Removing grease does not define the necessary rating. Grease removal might involve detergent, heat, mechanical force or a combination of all three.
Your cleaning specification should identify:
- The washer or hose supply and its operating pressure.
- Nozzle type, spray pattern and water flow at the operating setting.
- Minimum nozzle-to-enclosure distance, including foreseeable close approaches.
- Maximum water temperature and the enclosure temperature before cleaning.
- Detergent or sanitizer identity, concentration, contact time and rinse procedure.
- Cleaning frequency, spray directions and time spent on seals or mounted devices.
Measure distance to the nearest exposed feature, not simply the center of the door. A projecting switch or cable gland can receive a closer jet than the surrounding sheet metal.
Water temperature deserves a separate limit. Hot cleaning can affect gasket properties, mounted electronics and pressure changes as the enclosure cools. Use the article on washdown water temperature and enclosure exposure when documenting those conditions.
Why the pressure gauge cannot select the rating
A washer gauge usually describes pressure upstream of the nozzle. It does not directly describe the water loading at the door gasket. Nozzle geometry, flow, distance and jet breakup all affect that loading.
A narrow jet concentrates force over a small area. A broad spray distributes it differently, even with the same upstream gauge reading. Moving the nozzle closer can also change the exposure substantially.
There is therefore no universal washer-pressure cutoff that separates IPX5 from IPX6. Do not compare a pump gauge with a quoted laboratory pressure and declare the installation suitable.
Keep the required water digit
Under IEC 60529, the final digit identifies water protection. IPX5 concerns water jets; IPX6 concerns powerful water jets. The X means the designation does not assign a solid-particle protection level. It does not mean the enclosure has no dust resistance.
The standardized tests use defined nozzles, flow rates, distances and durations. For orientation, IPX5 uses a 0.25 in [6.3 mm] nozzle delivering approximately 3.3 US gal/min [12.5 L/min]. IPX6 uses a 0.49 in [12.5 mm] nozzle delivering approximately 26.4 US gal/min [100 L/min]. Both use a specified distance of approximately 8.2–9.8 ft [2.5–3 m].
Those values describe controlled tests, not permission to use any washer with an apparently comparable pressure. The IP65 versus IP66 water-jet test comparison explains the test differences in more detail.
Use these selection rules:
- Consider IPX5 when the documented cleaning exposure is compatible with the assembly manufacturer's water-jet limits.
- Require IPX6 when the project specifies water protection level 6 or the assessed exposure requires powerful-jet protection.
- Request application review for hot water, high-pressure cleaning, close-range jets or aggressive chemicals. IPX6 alone does not qualify those conditions.
- Evaluate immersion separately. A jet rating does not establish submersion protection.
For a complete code, assess dust independently. IP56 combines dust protection level 5 with water protection level 6. IP65 combines dust protection level 6 with water protection level 5. Neither is simply the higher rating overall. An IP66 design combines dust-tight protection with water protection level 6, but still needs application-specific review.
We offer specified designs rated NEMA 4X / IP66 by the manufacturer; not UL listed. In US installations, an IP code does not replace the required enclosure type rating. Use the NEMA 4, NEMA 4X and IP66 guide for that distinction. Establish any listing requirement before choosing the enclosure.
Choose material for the cleaning chemistry
Water protection and chemical resistance are separate decisions. An enclosure can exclude a test jet yet suffer corrosion or gasket damage during repeated cleaning.
For custom stainless designs, we offer 304 stainless steel for indoor washdown and many outdoor applications. We also offer 316L stainless steel for salt air, brine, chlorides, pharmaceutical and chemical areas.
Choose between them using the actual chemical exposure. Include concentration, maximum temperature, dwell time and whether deposits remain after rinsing. The presence of chlorides supports reviewing 316L, but does not make every chloride exposure acceptable. Neither stainless grade is immune to unsuitable cleaning chemistry.
Apply the same review to the complete sealing system. Door gaskets, gland seals, switch boots and viewing-window seals may use different materials. Obtain compatibility information for each material at the stated temperature and concentration.
Do not specify a gasket solely because its generic material name sounds suitable. Formulation, compression and joint design also matter. Ask for confirmation against your cleaning schedule rather than assuming the metal grade protects every component.
Where salt exposure also influences the decision, the article on salt-water exposure and enclosure distance explains why distance alone is insufficient.
Size the enclosure without creating a cooling problem
Select usable internal dimensions after choosing the protective construction. External dimensions do not establish backplate space, door clearance or cable-bending room.
Prepare a scaled layout with component outlines, wiring ducts, terminal access and required separation. Include the space occupied by glands, door-mounted devices and their rear connections. Follow the electrical enclosure sizing guide for the dimensional fundamentals.
For example, a hypothetical depth stack might contain 5 in [127 mm] of equipment projection, 1 in [25 mm] of mounting stand-off, and 2 in [51 mm] of required front clearance. That already requires 8 in [203 mm] of usable depth before allowing for inward-projecting door hardware. It does not establish an 8 in external enclosure depth.
Calculate heat from component losses, not their output ratings. If documented losses are 40 W, 30 W and 20 W, the internal load is 90 W before other sources. Assess that load at the maximum installation ambient temperature, including solar gain where applicable.
A larger shell may improve passive heat rejection, but it does not guarantee acceptable component temperatures. Opening a ventilation hole can also defeat the selected water protection. Where cooling is necessary, specify an assembly compatible with the environmental requirement and verify its capacity under actual conditions.
The outdoor enclosure heat-gain assessment helps separate internal losses from external heating.
Protect every mounting and sealing interface
The enclosure shell is only one part of the water barrier. Door hardware, cable entries, displays, switches and mounting penetrations must suit the same cleaning exposure.
Locate entries away from direct spray where practical. Bottom entry can reduce direct exposure, but it is not automatically watertight. Water can follow a cable toward its gland, so provide suitable cable routing and strain relief.
Select each gland for the actual cable diameter and jacket shape. Check its sealing arrangement, permitted mounting thickness and installation torque. A gland intended for one round cable is not automatically suitable for several smaller cables.
Use the cutout, gland and HMI-window guide when preparing the penetration drawing. Avoid placing openings where they interfere with gasket compression, door reinforcement or internal components.
For door-mounted controls, verify the device's installed rating, gasket position and permitted panel thickness. The article on panel-mount switch sealing for washdown addresses that interface specifically.
Mount the enclosure without twisting its body or distorting the door opening. Provide access for inspecting the full gasket perimeter and replacing seals. Do not assume that tightening latches harder will correct an uneven mounting surface.
After assembly, inspect gasket continuity, gland engagement, unused-hole plugs and door closure. Remove swarf and contamination before closing the enclosure. Arrange any verification through the responsible manufacturer or a qualified test provider; spraying energized equipment is not an acceptance method.
The article on enclosure ratings after cutouts and device installation explains why individual component ratings do not automatically establish the finished assembly rating.
Put the cleaning limits on the order
Specify the required protection and the conditions it must address. Writing only “washdown enclosure” leaves critical assumptions unresolved. Writing only IPX6 leaves the solid-particle requirement unresolved as well.
Use the following table to define the order and drawing review. Record actual values rather than replacing unknown conditions with a stronger-looking code.
| Specification item | What to put on the order | What must be confirmed |
|---|---|---|
| Required protection | Complete IP code, required NEMA type and any listing requirement | Suitability of the specified design and finished assembly |
| Cleaning equipment | Washer or hose details, operating pressure, nozzle and flow | Compatibility with the actual jet exposure |
| Spray limits | Minimum distance, permitted directions and exposure duration | Whether close-range or concentrated jets require further evaluation |
| Temperature | Maximum cleaning-water temperature and installation ambient | Seal, device and thermal suitability |
| Cleaning chemistry | Product identity, concentration, contact time and rinse method | Compatibility of metal, gaskets and exposed components |
| Material | Selected grade, such as 304 or 316L stainless steel | Suitability for cleaning chemicals and surrounding exposure |
| Dimensions | Width, height, depth and required usable clearances | Backplate layout, door clearance and cable-bending space |
| Heat | Documented component losses and any external heat gain | Acceptable internal temperatures and suitable cooling provisions |
| Penetrations | Dimensioned cutouts, cable sizes and installed device details | Sealing method, mounting thickness and assembly protection |
| Mounting | Orientation, support details and available service space | No shell distortion or inaccessible sealing interfaces |
When these requirements are established, use the enclosure selector to narrow dimensional and environmental choices. A dimensional match still needs a separate thermal check.
For a design requiring your own dimensions and penetration layout, specify the material, width, height, depth and every cutout through custom enclosures. Custom work starts from the approved drawing. High-pressure or hot washdown requires application review rather than an assumption that IPX6 covers every cleaning method.
Enclosures for this job
Catalog sizes that suit the job this article answers, picked from its subject; open one for its full specifications.
| Enclosure | Material | Outside H x W x D / display | Rating |
|---|---|---|---|
| 16 × 14 × 8 in | 316L stainless | 16 x 14 x 8 in | Rated NEMA 4X / IP66 by the manufacturer; not UL listed |
| 24 × 20 × 8 in | 316L stainless | 24 x 20 x 8 in | Rated NEMA 4X / IP66 by the manufacturer; not UL listed |
| 16 × 12 × 8 in | 316L stainless | 16 x 12 x 8 in | Rated NEMA 4X / IP66 by the manufacturer; not UL listed |
Questions
Can I choose IPX6 from the pressure shown on a washer gauge?
No. A washer gauge generally measures pressure upstream of the nozzle. The exposure at the enclosure also depends on nozzle geometry, flow, distance and spray pattern. IPX6 describes performance under a standardized water-jet test, not a universal allowable pressure for every cleaning system.
Is IP65 an acceptable replacement for IP56?
Not when water protection level 6 is required. IP65 has a higher dust-protection digit than IP56, but a lower water-protection digit. Evaluate the digits independently. IP66 combines dust-tight protection with water protection level 6, subject to the specified assembly and application conditions.
Does IPX6 cover hot pressure washing?
IPX6 alone does not establish suitability for hot pressure washing. Cleaning-water temperature, concentrated jets, minimum nozzle distance and chemicals need separate review. Obtain confirmation for the complete assembly, including its door seals, cable entries and mounted controls, against the actual cleaning procedure.
What does the X mean in IPX5 or IPX6?
The X means that the designation does not assign a solid-particle protection level. It does not establish that dust can enter, or that the enclosure is dust-tight. If dust protection matters, specify the required first digit as part of a complete IP code.
Will choosing 316L stainless steel improve the water rating?
Changing the metal grade does not raise the water-protection rating. Grade selection addresses corrosion exposure, while water protection depends on the enclosure construction and sealing interfaces. Consider 316L for chloride-related exposure, but review the actual chemical concentration, temperature and contact time before specifying it.
