⚡ NEC Quick Hit: Schedule 40 PVC & HDPE Conduit ⚡

 The most common plastic raceways on the job! Schedule 40 PVC (Article 352) and HDPE (Article 353) share identical Chapter 9 dimensions. Let's break down the numbers from 1/2" to 6" 👇

SLIDE 2 (SMALLER TRADE SIZES) Small Sch 40 & HDPE Trade Sizes:

• 1/2" (Metric 16)

  • 100% Total Area: 0.285 in²

  • Over 2 Wires (40%): 0.114 in²

  • ID: 0.602 in.

• 3/4" (Metric 21)

  • 100% Total Area: 0.508 in²

  • Over 2 Wires (40%): 0.203 in²

  • ID: 0.804 in.

• 1" (Metric 27)

  • 100% Total Area: 0.832 in²

  • Over 2 Wires (40%): 0.333 in²

  • ID: 1.029 in.

SLIDE 3 (MEDIUM TO LARGE SIZES) Medium to Large Sizes (40% Fill Limit):

• 1-1/4": 0.581 in² (100% = 1.453 in² | ID: 1.360 in.)

• 1-1/2": 0.794 in² (100% = 1.986 in² | ID: 1.590 in.)

• 2": 1.316 in² (100% = 3.291 in² | ID: 2.047 in.)

• 3": 2.907 in² (100% = 7.268 in² | ID: 3.042 in.)

• 4": 5.022 in² (100% = 12.554 in² | ID: 3.998 in.)

⚠️ Note: Just like PVC, 3/8" trade size is skipped—standard runs start at 1/2".

SLIDE 4 (WRAP-UP) 💡 Apprentice Pro-Tip: 

Because Articles 352 and 353 map to the same Chapter 9 table, whether you're pulling underground HDPE or running Sch 40 PVC stub-ups, your fill calculations stay completely consistent!

💬 Save this post for your next underground trench or slab rough-in! 🔗 More code breakdowns & study tools at www.JoshTheSparky.com