AG FRE® Conduit Frequently Asked Questions

1. Question: What US and Canadian standards apply to FRE® Above Ground products?
Answer: Underwriters Laboratories’ and the Canadian Standards Association’s Standard for Reinforced Thermosetting Resin Conduit (RTRC) and Fittings, UL 2515 / CSA C22.2 No. 2515, provides the requirements for both Standard Wall (SW) and 4” ID Heavy Wall (HW) Above Ground products.

2. Question: What is the difference between UL 2515 and CSA C22.2 No. 2515?
Answer: None. They are a single harmonized binational standard developed through the CANENA working group.

3. Question: Can we comply with both UL 2515 / CSA C22.2 No. 2515 and NEMA TC-14 at the same time?
Answer: Yes. The National Electrical Manufacturers Association (NEMA) adopted the latest version of UL 2515 / CSA C22.2 No. 2515 as its own industry standard, NEMA TC-14.

4. Question: What are the key differences of the Above Ground compared to the Below Ground product offerings? (resin mixture, properties, specifications, etc.)?
Answer: Section 355.100 of the National Electrical Code (NEC) and rule 2-130 of the Canadian Electrical Code (CEC) specify the additional considerations that must be made for Above Ground Rigid Nonmetallic Conduit (RNC) products. This includes the addition of flame retardants and UV inhibitors.

5. Question: Can you direct bury or concrete encase FRE® Above Ground products?
Answer: Yes. FRE®’s Above Ground products can be used in all of the same locations as its below ground products, along with concealed and exposed locations where not subject to physical damage. This includes direct burial and concrete encasement applications.

6. Question: Can an FRE® TriSealTM joined conduit run be installed in high vibration areas?
Answer: The use of epoxy adhesive in conjunction with the FRE® TriSealTM joint is recommended for installations where the conduit system may be subjected to considerable vibration.

7. Question: Do we have a comparison chart between PVC, Steel and other products?
Answer: A table comparing RTRC’s properties to other types of Rigid Nonmetallic Conduit (RNC) as well as Rigid Metal Conduit (RMC) is currently under development and will be added to this website as soon as it is available.

8. Question: What flame requirement does the FRE® Above Ground product line meet?
Answer: FRE®’s Above Ground product line complies with the 5” (127 mm) Flame Retardant Properties Test specified in the Standard for Reinforced Thermosetting Resin Conduit (RTRC) and Fittings, UL 2515 / CSA C22.2 No. 2515.

9. Question: On the spacing of supports for FRE® conduits, is it mandatory to use the spacing specified in the National Electrical Code (NEC) or Canadian Electrical Code (CEC) for rigid nonmetallic conduit?
Answer: No. If the installation does not have to be in accordance with NEC or CEC provisions you can space hanger supports much further apart for FRE® conduit than for PVC due to its higher flexural strength. FRE Composites publishes a hanger span and deflection table in its AG catalog, which will guide you through your project or installation.

10. Question: Can you bend FRE® Above Ground conduit in the field?
Answer: In the U.S., FRE® Above Ground conduit can be bent in the field for larger radius elbows using standard RNC bending equipment and carefully following our manufacturer’s instructions, in accordance with 355.24 of the National Electrical Code (NEC). This installation advantage is made possible because of our 68 % ± 3 % glass to resin content. RTRC products with a higher glass content will severely restrict this capability.

11. Question: Why do we recommend Heavy Wall Above Ground products in some specific applications? Answer: Heavy Wall (HW) products are recommended for applications where mechanical strength in excess of that provided by the Standard Wall (SW) products is desired. However, neither the SW nor HW products are listed for locations where they would be subject to physical damage. 12. Question: Can you make an epoxy joint with FRE® Above Ground conduit system products?
Answer: Yes. Our epoxy adhesive kits consist of either the mixture of two (2) distinct components (40-0161) or a dual cartridge system (20-0164) that pre-mixes the adhesive before it is applied to the conduit. It is recommended that the TriSealTM joint system be removed when using an adhesive.

13. Question: When you do a bridge job, must adhesive joints be used at each joint?
Answer: No. An epoxy adhesive joint is only necessary when excessive vibration or movement in the bridge structure is anticipated which would require additional resistance to decoupling (greater than 500 lb. pullout). Otherwise a TriSealTM joint will provide a suitable connection.

14. Question: Are TriSealTM joints acceptable?
Answer: Yes. Our proprietary design, one-piece molded urethane TriSealTM ensures, when installed per manufacturer’s instructions, a watertight joint as defined by the National Electrical Code (NEC) and Canadian Electrical Code (CEC).

15. Question: How much travel do you get with an O-ring or single expansion joint?
Answer: An O-ring or single expansion joint provides 6” (152 mm) of free travel in either direction for a total of 12” travel.

16. Question: Should you use a radius bell end fitting when you pull cable into a junction box?
Answer: No. For connection to a junction box, a male threaded adapter should be used.

17. Question: Can you use FRE® Above Ground products in a Class 1 Division 2 area?
Answer: In the U.S., FRE® Above Ground products can be used in a Class 1, Division 2 location if they are encased in a minimum of 2” (51 mm) of concrete and provided with not less than 24” (610 mm) of cover, in accordance with 501.10(B) of the National Electrical Code (NEC). However, in Canada, the Canadian Electrical Code does not permit any type of Rigid Nonmetallic Conduit (RNC) to be used in these locations.

18. Question: Is the FRE® Above Ground product resistant to most chemicals?
Answer: Yes. FRE’s Above Ground conduit is not affected by exposure to most chemicals. Additionally, Reinforced Thermosetting Resin Conduit, elbows, bends and other fittings can be UL Listed and CSA Certified for direct exposure to specific reagents, identified by the designation "Reagent Resistant" and marked to indicate the reagents with which it was evaluated. Contact the manufacturer if additional, specific information is required.

19. Question: When do you use an FRE® wobble or skew wobble coupling?
Answer: Wobble and skew wobble couplings are used to accommodate minor horizontal or/and vertical curvatures of up to 3° and 7-1/2°, respectively.

20. Question: When you order a heavy wall conduit, do you get heavy wall fittings and accessories?
Answer: A complete line of heavy wall fittings is available including: Double Bell Couplings, 5 Bell Couplings, Sleeves, Male and Female Adapters, Single and O-Ring Expansion Joints, 90, 60 45, 30, 22-1/2, and 11-1/4 Elbows in a variety of radii, Wobbles and Skew Wobbles, Multifit Adapters, O-Ring Expansion/Deflection Couplings, Split Stop Rings and Reducers.

21. Question: What is the temperature rating for the FRE® Above Ground products?
Answer: It is UL Listed and Certified for a temperature range of -40 °F to 230 °F (-40 °C to 110 °C). However, epoxies are known to perform well in high temperatures (up to 275 °F or 135 °C).

22. Question: When you bend FRE® product in the field, is it still UL Listed?
Answer: As with any type of rigid conduit, whether metal or nonmetallic, once the product has been modified in the field it is no longer considered a Listed product. This includes field bending. However, the National Electrical Code (NEC) recognizes this and, in 355.24, permits RTRC to be field bent provided that the bends are made with bending equipment that is identified for the purpose. The Canadian Electrical Code (CEC) prohibits all types of RTRC from being field bent in rule 12-1208.

23. Question: Does FRE® make tapered and straight threaded adapters?
Answer: FRE makes a complete line of National Pipe Threaded male and female adapters for both IPS and ID trade sizes in Standard Wall (SW) and Heavy Wall (HW) dimensions. Contact the manufacturer for your specific project needs.

24. Question: How does FRE®’s coefficient of thermal expansion compare to that of PVC?
Answer: FRE®’s coefficient of thermal expansion and contraction is 50 % lower than that of PVC.