RTDs are wire windings or other thin film serpentines that exhibit changes in resistance with changes in measure temperature using the positive temperature coefficient of electrical resistance of metals. The hotter they become, the higher the value of their electrical resistance. Platinum is the most commonly used material because it is nearly linear over a wide range of temperatures, is very accurate, and has a fast response time. RTDs can also be made of copper or nickel. o Advantages of RTDs include their stable output for long periods of time. They are also easy to calibrate and provide very accurate readings. o Disadvantages include a smaller overall temperature range, higher initial cost, and a less rugged design
Taking oral temperatures requires simply sticking the thermometer in the mouth and taking a reading after a minute. False. The thermometer sensor has to be in a specific area and requires specific conditions to result in accurate readings. While oral, rectal, gut and core body temperatures can slightly differ, they are well-correlated and oral temperature is lowest of the four. Furthermore, oral temperature is the most influenced by outside factors like drinking, chewing, smoking and breathing through the mouth. Intake of cold drinks and food will lower oral temps, while hot counterparts do the opposite.