correction concerning general licenses

[Catherine Mattsen <CRM@nrc.gov>]

Minor correction to Betty Schwab's summary
concerning exemptions and GL's: tritium exit
signs are generally licensed and exempt from
most of Part 20 with the exception of 20.2201
and 20.2202 concerning reports of theft or loss
and notification of incidents.  Note also, most
generally licensed materials are subject to
restrictions on disposal as specified in the
particular section, e.g. 31.5(c)(8) and (9) or
31.11(c)(4) and (5).