334.3 Securing and Supporting.

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Cable ties marked Type 2S and 21S have been evaluated for the support of cables.

Code Change Summary: Changes were made for cable ties used to support nonmetallic-sheathed cable.

The most common method used to secure and support nonmetallic-sheathed cables is staples but the NEC^® also allows cable ties, straps, hangers, or similar fittings.

Not all cable ties are created equal. Some have only been evaluated to secure or position a cable. UL considers a cable tie a “cable positioning device” and certifies them to UL 62275.

The information listed below can be found using UL Product Spec under product category ZODZ: (Pay close attention to the last paragraph below).

RATINGS

Type Designations for Products Investigated to ANSI/UL 62275

Type 2 — A Type 2 product retains 100% of its declared loop tensile strength (cable ties) or declared mechanical strength (fixing devices) after test conditions. The declared maximum operating temperature for products designated and marked as "Type 2" is based solely on performance criteria in ANSI/UL 62275. The polymeric material comprising the product has not been separately investigated for long-term thermal properties according to ANSI/UL 746B, "Polymeric Materials - Long Term Property Evaluations."
Type 21 — A Type 21 product retains 100% of its declared loop tensile strength (cable ties) or declared mechanical strength (fixing devices) after test conditions. The declared maximum operating temperature for products designated and marked as "Type 21" is limited to the Relative Thermal Index - Strength (RTI - Strength) at 1.5 mm (0.06 in.) thickness for the polymeric material that comprises the product. The RTI - Strength for the material is determined by separate investigation for long-term thermal properties according to ANSI/UL 746B, and the declared maximum operating temperature of the product is based on the performance criteria in ANSI/UL 62275.
Type 2S and Type 21S — Type 2S and Type 21S products meet the same requirements as Type 2 and Type 21 products, respectively, but have been additionally investigated for use as primary support for a flexible conduit, flexible tubing, or cable in accordance with the NEC^®. Such products may also be marked "Support" in lieu of the "S" designation.

Below is a preview of Article 334. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2017 NEC^® edition of NFPA 70.

2014 Code Language:

334.30 Securing and Supporting. Nonmetallic-sheathed cable shall be supported and secured by staples, cable ties, straps, hangers, or similar fittings designed and installed so as not to damage the cable, at intervals not exceeding 1.4 m (4 ½ ft) and within 300 mm (12 in.) of every outlet box, junction box, cabinet, or fitting.

2017 Code Language:

334.30 Securing and Supporting. Nonmetallic-sheathed cable shall be supported and secured by staples; cable ties listed and identified for securement and support; or straps, hangers, or similar fittings designed and installed so as not to damage the cable, at intervals not exceeding 1.4 m (4 ½ ft) and within 300 mm (12 in.) of every cable entry into enclosures such as outlet boxes, junction boxes, cabinets, or fittings.

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334.3 Securing and Supporting.

Below is a Real Question from our Electrical Continuing Education Courses for Electrical License Renewal:

Which of the following is required when supporting nonmetallic-sheathed cables?

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Answered: None Yet!

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	A:	Cable ties are NOT permitted.
	B:	Staples are NOT permitted.
	C:	Straps are NOT permitted.
	D:	If cable ties are used, they shall be listed and identified for securement and support.