How to get rid of "flash of expanded content" upon refresh?

Please take a look at the following website:

http://www.pottersignal.com/datasheets_firesprinkler.aspx

I'm using the toggle effect to create the expandable content here. However, when I click Refresh, you see a flash of the expanded content before it quickly collapses again. Is there any way to get rid of this?

Thanks!