Does anyone know the rules on using disc wheels for triathlons?

I haven't done triathlons before. The ITU rules state:
"For draft illegal competitions, covers are allowed on the rear wheel. However, this provision may be changed by the Technical Delegate in the interest of safety, i.e. high- winds; "

It only mentions wheel covers. Does that mean that discs are illegal in Triathlon?

Here's where I found the ITU rules. Page 24:
http://www.triathlon.org/docs/competition-rules-20080601-vf.pdf

discs are not illegal in non-drafting races.

Disc wheels are illegal on the front but not the rear in triathlon, unless advised by the organisers of that particular races. If it is a draft legal ITU race a rear discs is illegal.

 No distinction is made between wheelcovers and disc wheels.

Yeah, rear disc all the way.

And add a tri-spoke up front; OK it's not quite as fast as a 1080 at the front, but it sounds like a chinook and looks mean.

It depends on the type of triathlon race, they all vary and specific rules may apply for the event. You will not likley be entering a ITU governed event based on the question, so a rear disc is most likely ok.

The Lightweight disk is more comfortable then ful carbon disks.