There are several types of meat thermometers on the market today, each with their own merits. Firstly we need to decide if we want an analog or digital thermometer. Analog thermometers usually have a dial with an indicator showing the temperature, the drawback on these types is the scale used, some dont have a large enough range, to accurately indicate the meat temperature, so if you decide to buy an analog thermometer, ensure that the scale is clear and has markings to help you see temperature in one or two degree increments. Analog Thermometers usually also have the ability to recalibrate the thermometer, should it need it (see below).Digital Thermomters on the other hand will have a display which will show you exactly the temperature, some in 1 degree increments while others will show also in tenths of degree increments, reducing guess work with analog. Some Digital thermometers, also have extra features like warnings and alarms, a nice feature found in digital thermomters with corded/cordless probes, that allow you to set it and forget it. Be Sure you check if your thermomter is oven safe or not. Some thermometers are meant to be used out of the oven while some are oven safe and allow you to see the temperature rise as cooking progresses. The drawback to digital thermomters is that once it loses accuracy it is far too costly to repair and you'll end up having to buy another one.
The first thing is to figure out where the along the thermometer the indicator is taking its readings from. On some thermometers the readings come from the tip while others its set back from the tip. Why is this important? To accurately read meat temperature, we need to understand where the reading is coming from so we ensure we are not getting a false reading. For example if we insert the thermometer into the center of the meat and take a reading. A thermometer with the sensor on the tip, will tell us the temperature at the point, while one with a sensor further along the probe will give us a reading not from the center and the meat will not be at the desired temperature. When taking meat readings, make sure the sensor is not touching bone, and is inserted into the thickest part of the meat, for poultry always take readings from the tigh. To ensure a proper reading we suggest taking the temperature from two different locations to be certain. Also keep in mind the desired resting temperature, which is the temperature you want the meat to achieve. For example if you to cook a roast to 125 degrees, I would want to cook it to an internal temperature of 120 - 121 degrees, remove it from the heat source and as the meat rests, the temperature will continue to rise several degrees(4-5)(also know as carry over cooking) it is at this stage that you want the desired temperature to be reached. If you cook the meat, in the source till the desired temperature, you will overcook it, during the resting period.
We recommend testing your thermomter several times a year, especially before special occasions. To test the thermometer you have two options (limited by the scale reading of your thermomter). First option is to boil water, and use tongs to insert the stem into the boiling water, without touching bottom or sides. Within a minute the thermometer will have registered the temperature, and a reading of 212°F (100°C) (+/- 1-2 degrees is normal) should have been achieved (note boiling point changes with altitude check here). The other method is to put ice cubes into very cold water and place in the fridge to create a cold water slush, after a few minutes insert the stem into the coldest part, and you should get a reading of 32°F (0°C)(+/- 1-2 degrees is normal). If your thermometer is not reading accurately, and has the ability to recalibrate it, follow the specific instructions from your manufacturer. Some analog thermomters have a nut under the dial by the stem that is simply loosened, dial adjusted, and retightened(test again). Others, like the digital ones and some analog units are not adjustable and therfore should be recycled, and a new one purchased.