Full Electrical System Protection

Manufactured from mild steel, Columbia-MBF’s Rigid Conduit is highly resistant to damage from impact yet ductile to facilitate bending.

The ¾” taper NPT threads (ANSI B1.20.1) are full cut and hot galvanized after cutting. Color-coded end cap thread protectors keep the threads clean, sharp and also provide instant trade size recognition. Even sizes are color-coded blue, 1/2 sizes black, and 1/4 sizes red.

  • Hot-dip galvanized for outstanding corrosion resistance
  • High strength ductile steel for extended life and simple bending
  • Smooth, continuous raceways for rapid wire pulling
  • Kwik-Release End Cap to safeguard threads
  • Special orders are available on True Color GRC
  • Rigid conduit shall be Certified to CSA Safety Standard C22.2 No.45.1
  • Manufactured in accordance with ANSI C80.1
  • Available in trade sizes 1/2 (16) – 6 (155)


Hot-dip galvanized inside and out to deliver galvanic corrosion protection. Columbia-MBF Rigid Steel Conduit is top coated with a compatible organic layer to protect against white rust. The inside surface is evenly coated for ease in wire-pulling, even through multiple 90° bends.

EMI Shielding

Columbia-MBF Rigid Steel Conduit is very effective in reducing the effects of electromagnetic field levels for encased power distribution circuits, shielding computers and other sensitive electronic equipment from the effects of electromagnetic interference. Learn more with the GEMI (Grounding and Electro-Magnetic Interference) software analysis program.

Codes & Standards Compliance

Columbia-MBF Rigid Conduit is precision manufactured for reliable, extended value and supreme protection for electrical conductors. Covered by Section 12 of the Canadian Electrical Code (CEC), rigid steel conduit is highly resistant to damage from impact. It can be installed in projects and facilities ranging from standard commercial systems to the heaviest of industrial systems, including Class 1 Division 1 hazardous locations. Rigid steel conduit functions as an equipment bonding conductor when installed in accordance with the Canadian Electrical Code including Section10 Grounding and Bonding and Section 12-100 Rigid and flexible metal conduit. It is Certified to Canadian Standards Association Safety Standard C22.2 No.45.1 and is manufactured to ANSI C80.1.

Specification Data

Rigid Conduit shall be hot-dip galvanized and manufactured by Columbia-MBF. Threads shall be hot galvanized after cutting.  Rigid conduit shall be Certified to CSA Safety Standard C22.2 No.45.1 by a nationally recognized testing laboratory with follow up service. It shall be manufactured in accordance with ANSI C80.1.


Galvanized Rigid Conduit (GRC)

Trade SizeMetric DesignatorOutside Diameter1Nominal Wall Thickness2Approximate Weight per 100 Ft. (30.5M)Bundle Quantity
1 Outside diameter tolerances: Size 1/2 (16) to 1 1/2 (41) +/- 0.015” (0.38mm); 2 (53) to 6 (155) +/- 1%
Each length of conduit with coupling attached will be nominally 10’ (3.05m)
2 For information only. Not a requirement of the CSA Standard.
1 1/4351.66042.160.1333.3821898.925076.2
1 1/2411.90048.260.1383.51263119.325076.2
2 1/2632.87573.030.1934.90559253.610030.5
3 1/2914.000101.600.2155.46880399.210030.5