Final answer:
Tim should contact the Occupational Safety and Health Administration (OSHA) to address his concerns about the safety of his construction site.
Step-by-step explanation:
Tim should contact the Occupational Safety and Health Administration (OSHA).
OSHA is an agency of the United States Department of Labor that protects workers from physical harm in the workplace. It sets and enforces standards for safe and healthful working conditions, provides training and education, and investigates workplace complaints.
Examples of OSHA standards include requirements for employers to provide fall protection, prevent trenching cave-ins, ensure the safety of workers in confined spaces, and provide training for dangerous jobs.