Green without envy: solutions for mould on tape

Having spent a career restoring mould-ridden tape and film assets, I have learned that no library is immune from the challenges associated with mould — especially if they have not been in a climate-controlled environment. To date, I’ve cleaned 3,000 or 4,000 tapes that were mouldy, from all over the world. You would be surprised however, how many people are not proactively thinking about this issue. Obviously, mould is not good; it's not healthy for man, machine or tape. It's not as hard as some other tape issues to remediate, however it is still a big problem. If mould stays on a tape, and if it's not fixed, it will start eating directly into the tapes.

I try to explain to clients: if you know that your assets have mould, or suspect they might have mould, you need to get it cleaned up sooner rather than later. Mould can obviously be airborne; it can be contagious to other tapes nearby. When we clean or remediate these tapes, we also make sure to change the box or the container the tape was stored in so as not to recontaminate the newly cleaned media. It’s a small detail, but can make all the difference in the world down the road when you need that tape to play.

The trouble with ADAT – remember to look under the hood

One specific format is trickier than others: ADAT (or Alesis Digital Audio Tape) tapes that are mouldy inside their cassettes. Remember, ADAT became an extremely popular recording medium in the early 1990’s, which is almost 30 years ago. There are VHS cleaners that clean the tape pretty well, but the problem is that the tape stays in the cassette itself after cleaning. The cleaners bring the tape out of its shell just like it's being played on a VHS machine, but then it puts the tape right back into the cassette, where it is then recontaminated. The only real way to get this issue resolved is to take the tape out of the cassette housing, clean it, then decontaminate the cassette housing as well before putting the tape back in. Again, the devil is in the details.

We didn't see this issue until after it was raised during discussions at the AES International Conference on Audio Archiving, Preservation and Restoration held at the United States Library of Congress National Audio-Visual Conservation Center, and again at several AES Conventions. Then, all of a sudden, we were flooded with ADAT tapes that people have had in their basements or stored in closets or attics where the tapes were collecting moisture over a period of time — and these tapes just will not play. All of the above applies to video cassettes too, or any media format where the tape is enclosed in a cassette housing.

Mould on tape is pretty easy to fix once you know it’s there, but it is a problem that needs to be addressed for long-term viability of the precious media assets.