Tag Archives: DOT 51

cladding for insulation required under Special Provision TP38

Question:  Do we need to use stainless steel cladding when insulating tanks with 4″ insulation (as required for PIH products)?”

Tank Guru:  The insulation requirement for toxic products which are considered an inhalation hazard (special provision TP38) is as follows:  “Each portable tank must be insulated with an insulating material so that the overall thermal conductance at 15.5 °C (60 °F) is no more than 1.5333 kilojoules per hour per square meter per degree Celsius (0.075 Btu per hour per square foot per degree Fahrenheit) temperature differential. Insulating materials may not promote corrosion to steel when wet.”

In the simplest terms, 100mm (4″) of any of the normal insulating materials used on tank containers (mineral wool, fiberglass, polyurethane, etc.) more than meets the requirement.  And while it is most common to see tanks carrying PIH products with SS cladding, this is not required and any jacketing material will work.