Select the cells for the formatting.
Select Format and Conditional Formatting.
Change "Cell Value is" to "Formula Is" and enter the formula.
Then click format, pattern tab and select your color.
Click OK twice.
Your formula will color a cell if any cell in column I is less than or equal to 29.
If you wanted any cell that is less than or equal to 29 in column I to be highlighted, use the "Cell Value Is" in Conditional Formatting.
Hope this helps,
Deb