Page 217 - Facility Piping Systems Handbook for Industrial, Commercial, and Healthcare Facilities

CHAPTER 5

HEAT TRANSFER, INSULATION,
AND FREEZE PROTECTION

This chapter will discuss the basic fundamentals of heat transfer, thermal insulation, freeze
protection, and heat tracing.

CODES AND STANDARDS

Insulation is often regulated by code requirements. The individual sections of any code
must be carefully read in order to determine how flame-spreading or smoke-developing
characteristics restrict the use of particular materials in specific areas of a building.
Typically, codes define the class of any building erected into one of four types: I, II, III,
or IV. Type I is fireproof, Type II is noncombustible and either protected or nonprotected,
and Types III and IV are combustible. The allowable flame-spread rating for any construc-
tion material is based on each class of construction.
The specific areas within a building also have restrictions pertaining to the allowable
smoke-developed rating. These areas are:
1. Concealed spaces such as chases and shafts, not serving the HVAC system as air sup-
plies or returns.
2. The same spaces as above, but used for air supplies or returns.
3. Rooms and spaces that may have a higher allowable smoke-developed or flamespread
rating, such as mechanical equipment rooms. Here the interior finish and the insulation
fire code requirements are relaxed because of the nature of the space.
The building class as a whole usually determines the flame spread, and the specific area
within the building usually determines the smoke developed. It is important to determine
the most cost-effective insulation based on the code interpretations.

FUNDAMENTALS OF HEAT TRANSFER

BASICS

Heat is a type of energy that is produced by the movement of molecules. The greater the
movement, the greater the heat. All molecular motion stops at absolute zero.

5.1
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