Is it safe to scan curled negatives?

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When I did my radio show last week, I got a call at the last moment and answered it off the air. The question was from someone who had inherited a large box of negatives. She had a really smart question and I couldn't answer off the top of my head:

If I force a curled negative flat so I can scan it, will I damage it?

Well, I know it's unsafe to try to unroll a curled paper print. (Very bad idea.) But I wasn't sure if that was also true for film. I asked my buddy David Benjamin for some guidance. He's a photo archivist at the Wisconsin Historical Society.

This is what David told me:

• It's safe to scan.
• It's also OK to store flat in envelopes for a short time with a weight on top. This sometimes relaxes film back to a flatter state.
• He has personally unrolled film and seen no damage.
  
• Re-washing is waaay too dangerous. Don't even think about it.

Thanks, David.
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