Musty smell of old books

Musty smell of old books can be avoided – a personal experience

My home is full of books.  Books of all kinds, fiction and non-fiction, new and not so new – and that’s where a musty smell can become an issue.

As I find history fascinating, it won’t come as a great surprise when I tell you that many of my non-fiction books deal with historical subjects.  Not all the books I would like to read are easily available, be it online, at a library near-by or for sale at a high street shop.  Sometimes the only way to get my fingers on the book I desperately need is to buy it second hand.

A while ago, I ordered a copy of an out of print book, Alan B. Cobban’s The King’s Hall within the University of Cambridge in the Later Middle Ages, published in 1969.  Marks inside show that it spent the first 45 years of its life in a public library, until finding a home on my bookshelf.  Either the public headed the library’s warning written inside that “mutilation is punishable by law”, or was simply not too interested in the subject matter.   While its visual appearance is very good, it had a very strong musty smell, though no visible mould stains. As you can imagine, I was not entirely happy with my purchase.

Unfortunately, even the smell is an indication of mould.  For mould to develop moisture is needed.  This book probably had been stored in less than perfect conditions and had been exposed to a fairly high level of humidity for a long time.

We have all seen mould forming on food, which can be a sign that something has gone off.  I know, there are also instances where mould is desired, think of blue cheese for instance. However, in most cases mould is not what you want and that is not limited to the kitchen.  Provided there is a certain amount of moisture, mould can grow on any organic matter, including paper.  It can affect not only books, but many other items, which often have a high sentimental value, like photographs, family documents or your kids’ or grandkids’ drawings.

Musty smell of old books

A book’s best friend

Mould spores are everywhere, the air around us contains billions of them, and there is not much we can do about that.  However, we can influence the conditions they need to germinate, like humidity.

So, what did I do with my smelly book?  As I really wanted this specific book, sending it back was not an option and I had to find ways of dealing with it. I was fortunate with the weather.  At the time it was warm, very low humidity and a nice breeze, so I could just put it outside.  If at all possible, mould should be tackled outdoors.  You obviously want to get rid of the mould spores, not just redistribute them inside your home.  To do this, air movement is essential as it dries out the mould spores.  Should there not be sufficient natural air movement, you can increase ventilation with an electric fan.

Having gone to all this trouble removing the musty smell from my new acquisition, I obviously wanted to keep it like that.  It is important to store books in a clean, dry and stable condition.  However, this is often easier said than done.  Having too many books and limited space means they somehow need to be squeezed onto bookshelves. Good air flow cannot be ensured and I had to look for other ways to keep moisture away from my books.  This is where Pingi Moisture Absorbers can help.

Pingi Moisture Absorbers are bags filled with silica gel pellets, similar to the small paper bags you may find in a new handbag.  They absorb the moisture from the surrounding air.  Once they are saturated, they can be recharged in a microwave and are ready for use again.

I used to buy these absorbers based on calcium chloride, a mineral salt.  However, the results were anything but convincing.  When calcium chloride absorbs moisture, it dissolves.  The solution is collected at the bottom of the container and then chucked out.   They need constant refilling, which over time gets quite costly. The biggest problem though is the liquid which accumulates in the bottom of the container.  The whole container can easily be knocked over and the liquid spills all over the place.  This happened to me more than once, and our inquisitive cat also managed it.  (Fortunately, he had better sense than to lick the spill, which should not be ingested.)  Clearly, this would be really messy on a bookshelf and instead of solving a problem, it just creates new problems.

I discovered Pingi Moisture Absorbers three years ago at a trade fair in Frankfurt.  When I saw them, my immediate reaction was “I need these!”.  To cut a long story short, we started importing them into Australia and distributing them here online.  As you can imagine, I use Pingis all over the house.  The initial expense might be somewhat higher than with calcium chloride absorbers.  However, as they do not need refilling and can be recycled again and again, they are over time a much more cost-effective option.  And above all, they won’t leak and can be placed virtually anywhere – even in a bookcase.  Pingis can be placed behind the books so you won’t see them. Behind the scenes, they will absorb the moisture in the surrounding air and thus keep the humidity in the immediate environment of the books at a low level.

The musty smell of old books can be avoided.

Some useful references:

Pingi Australia

The State Library of Victoria has extensive information on conserving books and other paper objects covering topics from pests and mould to storage and framing.

There are several sites with good tips on how to remove mould from books:

Cornell University Library

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