It’s not uncommon to find yourself working on applications that were often build before the widespread adoption of CSS. Alongside legacy <table> based designs, the use of various mechanisms to prevent word-wrapping are often implemented.
I’ve found that the following allows for low-risk transition between technologies…
<style type="text/css">
table.nobr tr th, table tr.nobr th, table tr th.nobr, table thead.nobr tr td, table tbody.nobr tr td,
table.nobr tr td, table tr.nobr td, table tr td.nobr, table thead.nobr tr td, table tbody.nobr tr td,
.nobr {white-space:nowrap;}
</style>
With the above approach, you can apply class="nobr" to any element directly, for <table>‘s I’ve taken it a little further and allowed for the class to be set at various levels in the heirarchy to fill various needs.