NEQ text string

Hi. I have an If statement to see if N/A or NA is in a text box. If it is, I don't want to send an automated email I have set up. This works great if only N/A or NA is in the text box, but what if someone writes something like "N/A This component does not work for this part." How do I test this if the text box starts with N/A or NA and has text after it still? Here's my If Statement:

<cfif isDefined("form.Open_Jobs_Affected#id#") and evaluate("form.Open_Jobs_Affected#id#") neq "N/A" and evaluate("form.Open_Jobs_Affected#id#") neq "NA">

Thanks for your help.

Andy