Accuracy
The resolution of a digital consumer product is usually given, but this is not to be confused with the product’s accuracy. Its resolution is the smallest increment that it is capable of displaying, or more simply put, how detailed the data it collects is. Its accuracy is how close the measurement will be to the actual value of what you are trying to measure.
For some of the products that we offer, the manufacturer neglects to give the accuracy. For instruments that measure temperature, the accuracy can be assumed to be ±1°C. For those that measure humidity, the accuracy is probably around ±5%. Please keep in mind that inaccuracy multiplies based on how many sensors you are using. For example, if you use two sensors both with accuracies of ±1°C, they can differ by up to ±2°C.
In general, the accuracy of a weather barometer is unimportant because it will be adjusted for relative sea level and altitude. It is actually more important to see the trend and linearity with a barometer than accuracy.
Typically, a conformance standard supports electronic equipment that is manufactured to have a certain level of accuracy. This tells you that every product is manufactured to that same standard and has achieved the same accuracy.If you insist, most equipment like this can be calibrated at a local test house, but keep in mind that this will usually be a pointless endeavor. This is especially true when it comes to sending a barometer for calibration as you will just have to adjust it for altitude when you get it back. It is up each individual user to decide for themselves what accuracies are acceptable and balance this with how much it will cost to get an instrument that can perform to suit their needs.