| Too Hot to Be Measured With Thermocouples |
| Too Large to Be Measured Without a Very Large Number of Thermocouples |
| Moving Too Much for Thermocouple Lead Wire to Accept Without Breaking |
| At So High an Electrical Potential That Use of a Thermocouple Would Be Dangerous |
| So Low in Mass That The Thermocouple Itself Will Affect the Unknown Surface Temperature |
| Too Fragile or Wet to Accommodate Thermocouple Contact |
| Too Active (Chemically) to Accept a Thermocouple or Its Probe |
| In an Atmosphere That Is Hostile to a Thermocouple |
| Inaccessible to a Thermocouple or Its Instrumentation |
| Near Noise Producing Electric or Magnetic Fields |