HEPA Terminal Housing & Diffuser Selection Guide (H13/H14, Ceiling Interfaces)

Select the terminal as a ceiling system component

A cleanroom HEPA terminal housing places the final filter at the supply-air end of the duct system. The room-side diffuser then distributes filtered air through the ceiling or, for some outlet configurations, a wall opening. Selection therefore involves more than choosing a filter efficiency: the housing, duct connection, ceiling interface, seal arrangement, diffuser face and maintenance access must work together.

In this guide, hepa filter housing, hepa diffuser and hepa terminal box describe industrial cleanroom equipment connected to a supply-air system. They do not describe a consumer air-purifier “HEPA box.”

SENPEI’s air supply and filter housings hub groups four relevant families: HEPA terminal housings, standard HEPA supply outlets, gel-seal HEPA supply outlets and mesh-face HEPA outlets. Start with the family and service concept, then confirm airflow and dimensions against the ceiling and duct layout.

Map the four families

Family	Published construction	Main selection inputs
HEPA terminal housings	Top-adjustable, replaceable-media integrated or disposable integrated versions for ceiling installations	Version, ceiling type and module, filter class, duct entry and service approach
Standard HEPA supply outlets	Plenum box receiving air from the central air-conditioning system, final HEPA filter and room-side diffuser plate	Airflow, outlet count, ceiling module, plenum depth, duct inlet and project-specific dimensions
Gel-seal HEPA supply outlets	Gel channel mating with a housing knife edge, diffuser plate, and top-feed or side-feed construction	Feed direction, airflow, filter grade, duct space and optional regulating damper
Mesh-face HEPA outlets	Plenum box, final HEPA filter, filter collar and mesh diffuser face with perforated diffusion plate	Airflow, opening, installation depth, flange position, filter class and mesh-face arrangement

The standard outlet page does not publish a size, airflow or pressure-drop table. It states that detailed technical parameters are confirmed for the requested configuration. Do not transfer values from the gel-seal, mesh-face or terminal tables to a standard outlet.

Decide the ceiling interface and installation scope

Match the ceiling construction

The replaceable-media integrated terminal housing uses an anodized aluminium extrusion frame intended for T-bar, sandwich-panel, light-steel and lay-in ceilings. Its media pack is replaced from the room side while the frame remains in the ceiling. Three inlet sizes and an optional stainless outlet plate are published for this version; their applicability must be fixed in the quotation.

The top-adjustable version uses a compact powder-coated steel housing and diffuser plate. Filter position is adjusted from above, with side or top duct entry, while the filter remains reachable and replaceable from below. The disposable integrated version instead combines the frame and filter in a sealed unit that is replaced as one piece. It has an anodized aluminium, closed-cell-sealed frame and 10 mm PE insulation.

State the ceiling type and module size before comparing element dimensions. A filter element’s nominal dimensions do not define the housing cut-out, outer frame, suspension points or installation clearance.

Check the space above the diffuser

For a standard outlet, provide the available plenum depth and the duct inlet size and connection side. For a gel-seal outlet, choose top or side feed according to the duct and plenum space. For a mesh-face outlet, provide the ceiling or wall opening, installation depth, and duct flange size and position.

Published mesh-face constructions use a 380 mm casing depth with a 90 mm filter, or 500–600 mm depth with a 220 mm filter. These are configuration references, not a reason to omit the dimensioned installation drawing from the quotation process.

Assign site work clearly

Across these families, the equipment quotation covers the configured housing or outlet and its specified filter and diffuser arrangement. The buyer or buyer’s installer remains responsible for the applicable ceiling cut-out, mounting or suspension, reinforcement, duct connection, sealing between housing and ceiling, and final on-site testing. List sealing materials, replacement media or replacement filters explicitly when they are required in the supply scope.

Compare seals and service access

Gel channel and knife edge

In a gel-seal outlet, the filter frame sits in a gel channel that mates with the housing knife edge. Because the gel does not stick to the knife edge, the filter can be pulled and replaced from below without dismantling the housing. The diffuser plate and filter are removable for this service operation.

This is a published service-access feature, not a stated sealing class or leakage rating. If the project requires a particular installed leak-test method or acceptance criterion, specify it separately rather than inferring it from the words “gel seal.”

Replaceable media or disposable integrated unit

The replaceable-media terminal version retains its ceiling frame and changes only the media pack from the room side using retaining clips. This separates routine media replacement from removal of the ceiling frame.

The disposable integrated version takes the opposite approach: the sealed frame-and-filter assembly is replaced as one piece. Choose between these concepts according to the planned service operation, access route and quoted replacement scope—not from the H13 reference table alone.

Standard fixed stack

A standard outlet is quoted as a plenum box, HEPA filter and diffuser plate. Its page does not publish the gel/knife-edge service mechanism or the three terminal-housing versions. If room-side replacement, a particular seal interface or access from above is required, state that requirement and confirm the appropriate family before ordering.

For later filter measurement and replacement planning, see the HEPA replacement checklist.

Treat H13 as a reference and H14 as a confirmation

Under the EN 1822 classification explained in SENPEI’s EPA, HEPA and ULPA filter guide, H13 has a minimum overall efficiency of ≥99.95%, while H14 has ≥99.995%. The specification should identify the standard and class required by the project.

The terminal-housing table below lists H13 to EN 1822 filter elements for the disposable integrated version only. It does not establish H13 or H14 as the stock grade of every terminal housing. H14 and the other housing versions are confirmed with the quotation. On gel-seal RFQs, H13 or H14 to EN 1822 can be stated as the buyer’s required filter grade; this is an enquiry example, not a universal stock claim. Standard and mesh-face outlets likewise require the project filter class to be confirmed.

Filter efficiency alone does not guarantee a room’s ISO 14644 cleanliness class. Room classification depends on the complete cleanroom design, installation and operating conditions.

Use only the published airflow references

All values below are catalogue references. The quotation for the selected configuration is the binding document.

Gel-seal HEPA supply outlets

Housing size (mm)	Filter size (mm)	Airflow (m³/h)	Average face velocity (m/s)	Inlet flange (mm)	Inlet
460 × 460 × 250	390 × 390 × 90	500	0.9–1.1	200 × 200	Top
594 × 594 × 250	524 × 524 × 90	1000	0.9–1.1	320 × 200	Top
740 × 740 × 250	670 × 670 × 90	1500	0.9–1.1	400 × 200	Top
1035 × 730 × 250	965 × 660 × 90	2000	0.9–1.1	500 × 200	Top
1290 × 730 × 250	1220 × 660 × 90	3000	0.9–1.1	500 × 300	Top
460 × 460 × 400	390 × 390 × 90	500	0.9–1.1	200 × 200	Side
594 × 594 × 400	524 × 524 × 90	1000	0.9–1.1	320 × 200	Side
740 × 740 × 400	670 × 670 × 90	1500	0.9–1.1	400 × 200	Side
1035 × 730 × 400	965 × 660 × 90	2000	0.9–1.1	500 × 200	Side
1290 × 730 × 500	1220 × 660 × 90	3000	0.9–1.1	500 × 300	Side

Top and side inlets are separate configurations, including different housing depths. A downward-adjustable regulating damper is optional. Confirm all dimensions on the installation drawing.

Mesh-face HEPA outlets

Housing size (mm)	Filter size (mm)	Airflow (m³/h)	Average face velocity (m/s)	Inlet flange (mm)
390 × 390 × 380	320 × 320 × 90	500	0.9–1.1	200 × 200
554 × 554 × 380	484 × 484 × 90	1000	0.9–1.1	320 × 200
680 × 680 × 380	610 × 610 × 90	1500	0.9–1.1	400 × 200
680 × 1290 × 380	610 × 1220 × 90	3000	0.9–1.1	500 × 300
390 × 390 × 500	320 × 320 × 220	500	0.9–1.1	200 × 200
554 × 554 × 500	484 × 484 × 220	1000	0.9–1.1	320 × 200
680 × 680 × 500	610 × 610 × 220	1500	0.9–1.1	400 × 200
680 × 1290 × 600	610 × 1220 × 220	3000	0.9–1.1	500 × 300

Confirm length, width and height on the installation drawing. A downward-adjustment damper is optional. The efficiency class remains a project-specification confirmation.

Disposable integrated terminal H13 filter elements

Filter element size (mm)	Rated airflow / initial ΔP (m³/h)/(Pa)	Face velocity (m/s)	Media area (m²)	Low airflow / ΔP (m³/h)/(Pa)	High airflow / ΔP (m³/h)/(Pa)	Recommended final ΔP (Pa)	EN 1822
610 × 610 × 120	1000/160	0.73	10.9	600/90	1450/235	400	H13
610 × 915 × 120	1450/155	0.72	16.1	900/90	2200/235	400	H13
610 × 1220 × 120	1920/155	0.72	21.3	1200/90	2950/235	400	H13
610 × 610 × 150	1230/155	0.92	13.6	600/70	1450/190	400	H13
610 × 915 × 150	1810/155	0.90	20.1	900/70	2200/190	400	H13
610 × 610 × 220	1500/155	1.13	16.8	600/60	1800/190	400	H13
610 × 915 × 220	2230/155	1.11	24.8	900/60	2700/190	400	H13
610 × 1220 × 220	2950/155	1.10	32.8	1200/60	3600/190	400	H13

These are filter element sizes, not housing installation outer sizes. Confirm the values with the quotation. H14 and the other housing versions also require quotation confirmation, and the 400 Pa recommended final pressure drop depends on system conditions.

When to choose which family

• Terminal housings: choose when the project needs a defined ceiling-grid version—top adjustment, room-side media-pack replacement with a retained frame, or a disposable integrated frame-and-filter unit.
• Gel-seal outlets: choose when the gel/knife-edge interface and filter replacement from below without dismantling the housing are central to the service plan. Select top or side feed from the actual duct space.
• Mesh-face outlets: choose when the specified room-side arrangement is a mesh diffuser face and the published depth/filter combinations suit the new-build or retrofit opening.
• Standard outlets: choose when the brief is a central-AHU-fed plenum, final HEPA filter and diffuser plate, with detailed dimensions and airflow to be established for the requested configuration.

Operating-theatre laminar ceilings and leak-proof supply ceilings are different products on the same hub, not alternative names for these four terminal families.

Request-for-quotation checklist

Product family:
Terminal version, if applicable:
Ceiling or wall construction:
Ceiling module and opening size:
Available plenum or installation depth:
Required airflow per outlet:
Number of outlets / quantity:
Duct inlet or flange size:
Top, side or other required feed position:
Filter dimensions required by the project:
Filter class and standard (for example H13 or H14 to EN 1822):
Diffuser plate or mesh-face requirement:
Seal arrangement and required service access:
Top-adjustment or regulating/down-adjustment damper requirement:
Stainless outlet plate requirement, if applicable:
Ceiling sealing, replacement media or replacement filters in supply scope:
Project leak-test or final on-site test requirements:
Room cleanliness class as a project design input:
Destination country or port:
Packing requirements and requested installation drawings:

Configure the terminal with SENPEI

Review the three constructions on the HEPA terminal housings product page, then request a quotation for hepa-terminal-housings with the checklist above. For the sibling families, use the corresponding quotation links for standard-hepa-outlets, gel-seal-hepa-outlets or mesh-hepa-outlets. The quotation should fix the housing or outlet configuration, ceiling interface, filter class, diffuser arrangement and included service items before site installation begins.

Selected references

• SENPEI — What Are EPA Filters? (EN 1822 / ISO 29463)
• EN 1822 — HEPA/ULPA classification
• SENPEI — HEPA replacement checklist for post-selection service

Questions buyers ask