Redesignates existing paragraphs (11), (12), and (13) as paragraphs (12), (17), and (19), respectively; inserts new paragraphs defining: (11) passenger motor vehicle (as given in 49 U.S.C. 32101); (13) Secretary (means the Secretary of Transportation); (14) semitrailer (meaning given in 49 C.F.R. §571.3(b)); (15) side underride guard (definition describing its function and protections for Vulnerable Road Users); (16) single unit truck (defined as a large commercial truck, excluding any attached trailer); (18) trailer (meaning given in 49 C.F.R. §571.3(b)); and (20) Vulnerable Road User (meaning given in 23 U.S.C. 148(a)). Also makes technical amendments to punctuation in existing paragraphs (1)–(19).

Amends subsection (d) (section 23011(d) of the Infrastructure Investment and Jobs Act) to modify committee membership clauses, replace the meeting-frequency provision in paragraph (4) with specified meeting schedules before and after final regulations are promulgated under 49 U.S.C. 30130(a), change paragraph (6) wording from 'a biennial' to 'an annual', and add a termination date paragraph (7) setting committee termination on September 30, 2031. Also removes and reorders certain membership clauses and adds new membership categories for families of underride crash victims.

Adds new section 30130 to chapter 301 (Subchapter II of title 49) establishing rulemaking requirements for side underride guards on trailers, semitrailers, and single unit trucks, including an 18-month deadline to finalize regulations, specified performance standards (prevent intrusion up to 40 mph, impede passage of Vulnerable Road Users beneath vehicles, and contribute to fuel efficiency), required cost-benefit analyses, a 2-year compliance deadline after finalization, and periodic review beginning within 5 years and at least every 5 years thereafter.

Amends the analysis (table of contents) for title 49 by striking the item relating to section 30128 and inserting a replacement, and by inserting a new item after the item relating to section 30129.