Tool · Wyes, elbows and reducers
Duct fitting standard finder
Pick a duct standard (hose fittings, S&D PVC, Schedule 40, snap-lock or clamp-together metal) to see its marking, sizes and what it joins directly or by adapter.
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Short answer
Pick a duct standard to see what it covers, how it is marked, the dimensions its maker or standards body publishes, what it joins directly and which adapter joins it to dust-collection hose fittings. Keep each duct run to one standard and use adapters only where two meet.
Picks this tool points toSee the shortlist
- POWERTEC 70106 4 in Y-fitting dust hose connectorCheck price on Amazon
- POWERTEC 70136 4 in to 2‑1/2 in cone reducerCheck price on Amazon
- POWERTEC 70135 4 in aluminum blast gateCheck price on Amazon
- Dust-collection hose fittings (4 in nominal)
- Sewer-and-drain (S&D) PVC, ASTM D2729
- Schedule 40 PVC, ASTM D1785
- Snap-lock and crimped metal duct
- Clamp-together duct (Nordfab Quick-Fit)
Choose your fitting standard to see the key facts and what fits. Each fact links to its source on the full page.
What the table shows
| Fitting standard | What the standard or system covers | Marking to look for | Joins directly to | Joins only through an adapter | Application limits |
|---|---|---|---|---|---|
| Dust-collection hose fittings (4 in nominal) | A catalog family of fittings sized to slip into or over flexible hose and machine ports; no published standard sets their dimensions, and each maker's differ | Not confirmed | Flexible hose and, for some parts, machine ports: POWERTEC's 70136 fits 4 in and 2-1/2 in hoses; its 70291 friction-fits inside a 4 in nominal OD machine port; its 70291 small end fits inside most 2-1/2 in ID hoses | [S&D PVC](/fitting-standards/sewer-and-drain-pvc): Rockler says it does not connect directly to most dust fittings without an adapter. [Schedule 40 PVC](/fitting-standards/schedule-40-pvc): through Rockler's 52680 | POWERTEC says the 70136 fits hoses only and is not intended to fit a 2-1/2 in OD or 4 in OD equipment port directly |
| Sewer-and-drain (S&D) PVC, ASTM D2729 | ASTM D2729: PVC sewer pipe and fittings, covering materials, dimensions, workmanship, chemical resistance and joint tightness. ASTM lists D2729-21 as active | ASTM D2729 on the pipe: WoodRiver's page says pipe marked D2729 is suitable with its S&D adapter | Not confirmed | Most dust fittings, per Rockler. WoodRiver's 4 in adapter fits inside 4 in S&D with a 4.065 in ID and works only with left-hand threaded dust hose | ASTM's scope is sewer and drain pipe and fittings; it is not a dust-collection approval |
| Schedule 40 PVC, ASTM D1785 | ASTM D1785: PVC plastic pipe in Schedule 40, 80 and 120 sizes. ASTM lists D1785-26 as active, last updated August 28, 2026 | Iron Pipe Size conforming to ASTM D 1785 (Charlotte Pipe submittal) | Not confirmed | 4 in dust-collection fittings, through Rockler's 52680 | Charlotte Pipe: for pressure uses up to 140°F; never test with, transport or store compressed air or gas in PVC pipe or fittings |
| Snap-lock and crimped metal duct | Not confirmed | Not confirmed | Oneida's 6 in Super Dust Deputy models: ports sized for crimped ductwork fittings | Not confirmed | Not confirmed |
| Clamp-together duct (Nordfab Quick-Fit) | Nordfab publishes literature on Quick-Fit clamp-together ducting as a distinct duct system | Not confirmed | Not confirmed | Not confirmed | Not confirmed |
Five standards are listed: dust-collection hose fittings, sewer-and-drain (S&D) PVC, Schedule 40 PVC, snap-lock metal pipe and clamp-together duct. Each value comes from a standards body, a pipe maker or a fitting maker, with its source on the standard's page.
- S&D PVC. ASTM D2729 is the specification for PVC sewer pipe and fittings, and ASTM lists the D2729-21 edition as active.[1] Rockler says S&D pipe does not connect directly to most dust fittings without an adapter.[2]
- Schedule 40 PVC. ASTM D1785 covers PVC pipe in Schedule 40, 80 and 120 sizes, and ASTM lists D1785-26 as active.[3] Charlotte Pipe's submittal describes its Schedule 40 pipe as Iron Pipe Size for pressure uses.[4] Rockler lists a Schedule 40 to 4-inch fitting adapter (52680) with a 4.5-inch ID rubber end and a 3.99-inch OD plastic end.[5]
Standards are not approvals
ASTM D2729 and D1785 are plumbing standards. Neither addresses dust collection, and nothing on this site says a plumbing standard approves a dust system. We give no glue, cement or solvent advice; follow your collector maker's instructions for the duct it allows.
"Not confirmed"
A field marked "Not confirmed" means no source we verified states that value. Snap-lock and clamp-together duct have thin verified data, so many of their fields read that way. We do not fill gaps from seller listings.
Your pipe is not listed
Read the print on the pipe for its standard, then measure the end you have to join, inside and outside. The fitting standards guide explains each family.
Next
- Wyes, elbows and reducers: every page
- Sewer-and-drain vs Schedule 40 PVC
- A small-shop duct run parts list
- Dust-collection hose fittings (4 in nominal)
- Sewer-and-drain (S&D) PVC, ASTM D2729
- Schedule 40 PVC, ASTM D1785
- Snap-lock and crimped metal duct
- Clamp-together duct (Nordfab Quick-Fit)
Choose your fitting standard to see the key facts and what fits. Each fact links to its source on the full page.
Shop what this tool points toSee the shortlist
- POWERTEC 70106 4 in Y-fitting dust hose connectorCheck price on Amazon
- POWERTEC 70136 4 in to 2‑1/2 in cone reducerCheck price on Amazon
- POWERTEC 70135 4 in aluminum blast gateCheck price on Amazon
Questions
Does ASTM approve PVC for dust collection?
No. ASTM D2729 is the specification for PVC sewer pipe and fittings, and ASTM D1785 covers PVC pipe in Schedule 40, 80 and 120. Both are plumbing standards; neither addresses dust collection.[1][3]
Can I tell S&D from Schedule 40 by looking?
Read the print on the pipe: it names the standard, such as ASTM D2729 for sewer and drain or ASTM D1785 for Schedule 40. Our sources give no reliable visual rule, so trust the marking.[1][3]
What does "Not confirmed" mean?
No source we verified states that value for the standard. Several standards here have thin published data, and we leave those fields blank rather than guess.