Tug of war

An electrical inspector denied the use of this Article 360, -in. flexible metallic tubing (FMT) because it was used in lengths longer than 6 ft with low-voltage fire alarm equipment. Section 360.20 indicates that FMT smaller than metric designator 16 (trade size -in.) can't be used, except when it will be installed in accordance with 300.22(B) for ducts or plenums used for environmental air (in lengths
July 1, 2002

An electrical inspector denied the use of this Article 360, ⅜-in. flexible metallic tubing (FMT) because it was used in lengths longer than 6 ft with low-voltage fire alarm equipment. Section 360.20 indicates that FMT smaller than metric designator 16 (trade size ½-in.) can't be used, except when it will be installed in accordance with 300.22(B) for ducts or plenums used for environmental air (in lengths not to exceed 4 ft) and 300.22(C) (with no length restriction) in other spaces used for environmental air. The installer challenged the inspector, and suggested a “tug of war” with the same size of flexible metal conduit of the same length, and proved that the flexible metallic tubing was more durable. I wonder how many inspectors would approve the use as described?

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