Which installation is prohibited due to safety concerns?

Loose insulation around knob-and-tube wiring is prohibited due to significant safety concerns. This type of wiring, commonly found in older homes, can generate heat during operation. When loose insulation is placed around it, there is a risk that the insulation can trap heat, potentially leading to overheating and increasing the likelihood of an electrical fire.

Maintaining safe clearances around knob-and-tube wiring is vital to reduce these risks, which is why building codes typically prohibit the use of loose insulation in such scenarios. Proper installation practices call for either non-combustible insulation or designated clearance zones to ensure that wiring can dissipate heat safely and that there is no interference that could lead to fire hazards.