Fitting standard
Schedule 40 PVC, ASTM D1785, in a dust-collection run
ASTM D1785 covers Schedule 40, 80 and 120 PVC pressure pipe. Charlotte Pipe's 4 in socket figure, Rockler's 52680 adapter and the pipe maker's limits.
Also listed as Sch 40 PVC, Schedule 40, ASTM D1785
Short answer
Schedule 40 PVC is pipe made to ASTM D1785, which covers Schedule 40, 80 and 120 sizes; the active edition is D1785-26. Charlotte Pipe marks it Iron Pipe Size to ASTM D 1785 for pressure uses up to 140°F and lists a 4.509 to 4.527 in socket entrance ID on 4 in belled-end pipe. Rockler's 52680 joins it to a 4 in dust fitting with a 4.5 in ID rubber end. The catch: these are plumbing documents, not dust-collection approvals. See S&D vs Schedule 40.
Key facts
- What the standard or system covers
- ASTM D1785: PVC plastic pipe in Schedule 40, 80 and 120 sizes. ASTM lists D1785-26 as active, last updated August 28, 2026[1]A different standard from D2729 (sewer and drain).
- Marking to look for
- Iron Pipe Size conforming to ASTM D 1785 (Charlotte Pipe submittal)[2]
- Published dimensions
- 4 in belled-end pipe made to ASTM D 2672: socket entrance ID 4.509 to 4.527 in (Charlotte Pipe)[2]The submittal gives no pipe OD or wall values.
- Joins directly to
- Not confirmed
- Joins only through an adapter
- 4 in dust-collection fittings, through Rockler's 52680[3]
- Transition parts with stated ends
- Rockler 52680: 4.5 in ID rubber end and 3.99 in OD plastic end, joining a 4 in dust fitting to Schedule 40 PVC[3]Rockler sells a separate version for hose.
- Gates and fittings made to it
- Not confirmed
- Application limits
- Charlotte Pipe: for pressure uses up to 140°F; never test with, transport or store compressed air or gas in PVC pipe or fittings[2]The pipe maker's scope and warning, not a dust-collection approval.
- Not confirmed
- Not confirmed
Watch out for
- ASTM D1785 and Charlotte Pipe's submittal are pressure-plumbing documents; neither approves Schedule 40 for dust collection.
- Charlotte Pipe warns never to test with, transport or store compressed air or gas in PVC pipe or fittings. That is the pipe maker's own warning, quoted as written.
- Rockler's 52680 is for Schedule 40 pipe; Rockler sells a different version for hose, so match the version to what you are joining.
Questions
How do I join Schedule 40 PVC to a 4 in dust fitting?
Rockler lists its 52680 adapter with a 4.5 in ID rubber end and a 3.99 in OD plastic end for that join.[3]
Is Schedule 40 PVC approved for dust collection?
No source says so. ASTM D1785 covers PVC pipe in Schedules 40, 80 and 120, and Charlotte Pipe's submittal describes pressure uses up to 140°F.[1][2]
What does 'Iron Pipe Size' mean on the pipe?
Charlotte Pipe describes its Schedule 40 PVC as Iron Pipe Size conforming to ASTM D 1785. S&D pipe is made to a different standard, ASTM D2729. See duct fitting standards.[2][4]