Limited Quantity SCO?

["Quang Le" <qmle@icnpharm.com>]

Radsafers:
Is there such thing as a "limited quantity SCO (surface contaminated
object)"? 49CFR173.421 talks about limited quantities of Class 7 materials
and 173.427 talks about LSA and SCO. Are these mutually exclusive?
Specifically, someone I know is facing with shipping, domestically,  some
very mildly contaminated plexi shields (P-32, P-33 as contaminants). The
amount/concentrations of activities are undoubtedly under the limits for
"limited quantities". Reading 49CFR suggests that these could be packaged
in a "strong, tight package...The shipment be exclusive use... and some
other requirements. The question is whether the vehicle needs to be
placarded. 173.427(a)(6)(v) requires that it be placarded according to
subpart F of part 172. Well, subpart F of part 172 (the placarding section)
says it does not need to be if the material is offered for transportation
as Limited Quantities.
Any comments or guidance would be appreciated. I apologize if this has been
discussed on Radsafe previously.

Quang Le
<qmle@icnpharm.com>