NCCER
National Center for Construction Education and Research
NCCER offers a wide range of resources including Craft Certifications

NCCER Home Page
To find a local training or assesment center
For a list of Entry Level assesments available
For a list of Journey Level assesments available
Online store offers study materials for numerous crafts.

TWIC™ card
Transportation Worker Identification Credential

TWIC™ Home Page
Immigration status eligibility requirements pdf
Disqualifying Criminal offenses
Enrollment Center Locations
Enrollment, Appointment & Registration Page
Documentation Requirements
Card Status