I'm inclined to lump "loose/lose" in with "your/you're/ur (and even 'yore'!)" and "there/there/their". While it's easy to confuse them, there's really no excuse.

I don't remember seeing the "loose/lose" problem until fairly recently.

I looked at a couple of sample release forms for photographers I found on the Web, and most seem to give permission to take a photo, and also allow for the use, duplication and/or distribute the photo without a fee being imposed by the person whose image or photograph is used.

Here's a link to one of the samples:
http://www.eed.state.ak.us/aksca/pdf/photo_release_form_sample.pdf

I'm not a lawyer either, but my gut feeling on this one is that the AAA's family would sign a waiver, which would release the hospital from any liability.
To make matters more confusing, AAA's parents could sign a release, waiving their right to take legal action.

If I understand the question, when the condition is a phrase, I'd use "if" or "when" instead. For example, rather than "Under the conditions of high heat, the solution may oxidize rapidly," I'd use "When the temperature is above X degrees, the substance may explode," or "If the temperature exceeds X, then run for your life."

Is that an option?