Humidity indicator card

From Wikipedia, the free encyclopedia

There are very few or no other articles that link to this one.
Please help introduce links in articles on related topics. After links have been created, remove this message.
This article has been tagged since October 2006.

A humidity indicator card (HIC) is a card on which a moisture-sensitive chemical is printed such that it will change colour when the indicated relative humidity is exceeded. This item is a cheap way to quantify relative humidity levels inside sealed packaging. Used in semiconductor packaging.

The most common humidity indicator cards change color from blue to pink (base chemical is cobalt (II) chloride), but also cobalt-free brown to azure HIC's can be found on the market.

In the year 1998 European Community has issued a directive (adapting to technical progress for the 25th time Council Directive 67/548/EEC on the approximation of the laws, regulations and administrative provisions relating to the classification, packaging and labelling of dangerous substances) which classifies cobalt (II) chloride compounds containing Cobalt Chloride percentages (w/w) between 0,01 and 1 as an T (Toxic) and R49 (may cause cancer if inhaled). As a consequence new cobalt-free humidity indicator cards have been developed by some companies.