What were two reasons for the change of testing standards from NCHRP Report 350 to MASH?

• A. Increased size of vehicle fleet and cost considerations
• B. Increased size of vehicle fleet and increased understanding of safety performance
• C. Improved testing facilities and cost efficiencies
• D. Enhanced vehicle designs and safety protocols

Answer: (B)

The transition from NCHRP Report 350 to MASH (Manual for Assessing Safety Hardware) was largely driven by the increased size of the vehicle fleet and an enhanced understanding of safety performance.

The increased size of the vehicle fleet refers to the fact that vehicles on the road have evolved significantly, becoming larger and heavier over time. This shift necessitated a reevaluation of testing standards to ensure that safety hardware, such as barriers and guardrails, could effectively handle the impact forces generated by these modern vehicles.

Moreover, advancements in research and data collection have provided a greater understanding of how safety devices perform during real-world collisions. This knowledge has allowed engineers and safety professionals to develop more comprehensive and effective testing methods, leading to better design and performance criteria in MASH compared to the standards set forth in NCHRP Report 350.

Cost considerations and improved testing facilities, while relevant in the broad context of transportation safety research, are not the primary drivers behind the need for updated testing protocols in the shift from NCHRP Report 350 to MASH. Enhanced vehicle designs and safety protocols may indirectly benefit from these changes but do not capture the main reasons for the shift in standards.