/sys$common/syshlp/helplib.hlb RUN, Process, Qualifiers, /AST_LIMIT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /AST_LIMIT=quota

    Specifies the maximum number of asynchronous system traps (ASTs)
    that the created process can have outstanding.

    If you do specify an AST limit quota, the default quota
    established at system generation time is used. The minimum
    required for any process to execute is 2.

    The AST limit quota is nondeductible.