Humidity indicator cards are impregnated with a solution of cobalt chloride that has been carefully mixed to change color from
blue through various shades of magenta - red, to a pink. These cards are not precision indicators. However, they are very good
at telling you the maximum possible humidity in a container. For example if all of the dots are deep blue on a card which is a
10%- 60% card than you can be assured that the humidity in that container is below 10%. This is very important for some products
and household items because as long as the humidity is below 40%, basic corrosion (rust) will not occur. Neither will mildew or
mold in clothing or paper products. Finally, all sophisticated electronics: video cameras, computers, SLR cameras, sophisticated
instruments etc. enjoy a much longer and more reliable life if they are maintained at a very low relative humidity.
For example, at the bottom of this page are cards that were developed specifically for the electronics (computer chips) industry.
These companies require that the humidity in their shipping packages be below 10% and as of the guidelines established in the
fall of 1999 are striving to maintain humidity below 5%.
Product name | Humidity Indicator Card |
color change | Blue to pink |
Certificates | ROSH, REACH, Own Export License,ISO. |
Usage | Electronics Chemicals, PCB/IC /semiconductor /LED |