hatam_soferet | Torahs and humidity

In my email:

Hi Jen! I hope it’s okay if I ask you a quick question — the school I’m working at just paid a bunch to have our Torah repaired — lots of letter were flaking off. The sofer said this was due to humidity and…mentioned something about silicate powder, but we don’t know how much to get. Do you know anything about this subject? Thank you so much and chag sameach!

Background: when parchment gets humid, it expands, slightly and unevenly. I’ve posted before about how parchment sometimes goes cockly on warm days; see old post How a soferet knows it’s spring, for instance.The dampness causes small amounts of expanding and contracting.

The ink doesn’t expand or contract at the same rate as the parchment, and that’s where we run into difficulties. You’re probably all familiar with the effects; you’ve seen it happen on a t-shirt after it’s been through the laundry a few times.

click images to see bigger

Same thing happens to Torah letters, if they’re not well-guarded against humidity. Rapid changes are especially harmful.

REALLY bad humidity has even worse effects – worst of all when you have actual condensation, which causes real water damage, very hard to repair – but even when it isn’t that extreme, it can still be pretty bad, as in this next picture. There, the back of the parchment semi-melted and glued itself to the letters; when the scroll was unrolled, the letters stayed stuck to the back of the parchment, except in the places where the back of the parchment stayed stuck to the letters.

So what’re you supposed to do? How do you guard against humidity?

Aron design is part of it. If your aron kodesh is built into an exterior wall, and not damp-proofed, you’re setting yourself up for trouble. If you’re storing your sifrei torah in the boiler room during the week, likewise. If the aron lives right next to the heating unit, likewise. If you’re in Florida in the summer, likewise. Storing your sifrei torah away from the more obvious sources of moisture is a good idea, where possible.

If you’ve got no clue whether your aron is humid or not, there are humidity-testing devices out there. Hardcore cigar people have hygrometers in their cigar arons; you might borrow one from someone’s uncle. You can also pick one up on eBay, and they’re quite fun to have around so that you can grumble in the summer (”it’s 80% humidity today would you believe”). Also, every Jewish community has someone whose hair goes frizzy on humid days; put them in the aron and see if they come out complaining about their hair…no, I’m just joking. More info on humidity and testing here.

Museums face similar issues – even if they’re not in the boiler room or in Florida, museums store valuable documents in climate-controlled rooms, to prevent the same kind of damage we’re talking about here. Air-conditioning serves pretty well for climate control; one can also use a regular powered dehumidifier. Of course, using masses of electricity has its disadvantages.

The non-electric option is silica gel, that stuff that comes in packets in shoeboxes. It sits in the aron and absorbs atmospheric moisture; very clever, very handy. One can buy it in packages to suit particular volumes; it comes with a little indicator-thing so you can see how it’s doing, and when it’s absorbed as much moisture as it can hold, you dry it out in the oven and put it back. Here’s a nice FAQ about silica gel and the practicalities of how much to buy.

Mirrored from hasoferet.com.