What is the price of the commonly used wood moisture testers?
1: Extreme temperature
While most hygrometers should work fine at "normal" room temperatures, it requires a hygrometer specifically set up to withstand temperatures below freezing or above the boiling point of water. For example, a thermo-hygrometer exposed to temperatures below -4°F or above 140°F will start returning false readings.
Severely hot or cold prolonged periods of time without a specific design for extreme temperatures will not only degrade the accuracy of woodworking readings, but can also cause permanent damage to the meter's electronics, permanently rendering it useless.
2: Exposure to moisture
Ironically, prolonged exposure to excess moisture can actually cause damage to the hygrometer. This damage can manifest itself in a variety of ways, such as corrosion on the contact elements of the hygrometer (such as the pins of a pin gauge) or failure of the internal circuitry of the meter itself.
Anyone who's dropped a phone into a pool or other body of water can tell you that moisture and sensitive electronics don't get along very well. However, you don't have to put electronics in water to expose them to excess moisture. Leaving the meter in a wet environment, such as buried in a bag under wet overalls, can cause damage over time, as can dropping it in water.
3: Damage caused by mishandling
While woodworking moisture meters are often built to be rugged, long-lasting tools, improper field handling is still a leading cause of failure for these devices. That's not to say that these kinds of incidents are the user's fault; accidents do happen, such as meters dropped on hard surfaces or in buckets.
However, taking precautions to avoid mishandling a meter can go a long way toward preventing meter failure. For example, you can prevent accidents by holding the meter steady and secure and handing it to a colleague who needs to borrow it instead of throwing it across the room. Wearing gloves with gripping surfaces rather than slippery surfaces also makes it easier to avoid accidentally dropping the moisture meter during use.
As with any electronic product, a hygrometer will last longer when handled with care.
4: Exposure to pollutants
This is a problem that thermo-hygrometers are particularly sensitive to because their measuring elements are less easily replaceable than the pins on pin-type meters. Over time, when a thermo-hygrometer is repeatedly exposed to airborne chemicals, dust, mold, and other particles, these substances can deposit on the meter's measuring element. This causes the meter to provide inaccurate relative humidity readings over time, a phenomenon sometimes referred to as "drift".
As sensor drift gets worse, the gauge becomes less and less reliable, eventually leading to the need to completely replace the gauge with a new one. Unfortunately, you have no direct control over exposure to pollutants other than minimizing airborne particulates before using the hygrometer and keeping the meter itself clean and in good condition.
Ultimately, no hygrometer or thermohygrometer is completely immune to contamination.
5: Storage conditions
Where is your hygrometer stored when it is not in use? Storage conditions are an important part of proper care for any sensitive device, and hygrometers are no exception. Every item we have discussed in the above sections is important when storing a hygrometer.
For example, storing a hygrometer in a hot, damp, dirty box that sits loose in the back of a truck, bouncing around randomly, won't last nearly as long as a gauge kept in a proper suitcase . Delmhorst's hygrometers come with a case that protects the work between them.
But storage doesn't just mean you keep the meter between jobs. At work, keep your meter in the utility belt pouch while you're on the move? Having the meter in a pouch not only keeps your hands free for climbing ladders and other activities, it also keeps your hygrometer in a safe place where it is exposed to less contaminants, not to mention Less chance of discarding.
