Criteria for evaluating test item responses

1. Using the example of sitting around a campfire, give one example of how each of the following heat transfer mechanisms might be occurring:
   
   Radiation:
   Sitting around a campfire, you are heated by radiation from the fire.
   
   Conduction:
   A stick you are using to heat marshmallows is heating along its length by conduction.
   

   Convection:
   Heated air is rising above the fire, or alternatively there may be a breeze from a lake providing convection.

2. How are insulation and radiant barriers similar and different in terms of heat transfer? Give an example of insulation.
   
   Both can be used to reduce heat transfer. In the example of the underside of a hot roof deck, insulation may placed in contact with the roof deck to reduce conduction from it into the attic. A radiant barrier may be used under the roof deck as well— if the foil is facing up, it will reflect heat back up to the roof deck and therefore reduce heat transfer to the attic, or if the foil is facing down, the foil will not emit the heat well to the attic space, therefore also reducing heat transfer to the attic.
   
   Examples of insulation might include bubble wrap, foam, newspaper, cardboard, batt or blown fiberglass insulation.
   
   
3. Both infiltration and ventilation deal with outside airflow into and from buildings. Explain the difference in how the airflow occurs in infiltration and ventilation. Give an example of infiltration.
   
   Examples should identify a building that depicts air entering or exiting the building unintentionally and also intended mechanical ventilation. The mechanical ventilation may be used in the example as a means of providing outside air to the building when the unintentional air leakage is sealed.
   
   Examples of infiltration might include air leaks through cracks around windows and under doors, leaky electrical outlets, etc.