Answer:
When the material is explosive, oxidizing, poisonous, radioactive, corrosive, biohazard material.
Step-by-step explanation:
If the material is explosive, precautions must be high, and insulation serves to prevent explosion.
If the material is oxidizing or corrosive, the insulation serves to prevent spillage and damage to the structure.
If the material is poisonous, radioactive or biohazard, it must be insulated to prevent damage to the environment, structures, and nearby personnel operating it.
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