ASTM changes to the D4169 standard are officially implemented. Major updates specifically target the random vibration profile for truck transport. Previously, ASTM allowed users to select one of three assurance levels (each with a different intensity level). Regardless of assurance level, the schedule included random vibration for 60 minutes split evenly along the bottom, side, and end of the package.
In recent years, more data has become available regarding truck vibration. Using this data, the updated standard does away with the concept of assurance levels (note—this applies only to the truck segment, other hazards still include assurance level selection). Instead, the total duration of 60 minutes now includes a mix of what has been labeled “Low” – 40 minutes; “Medium” – 15 minutes; and “High” – 5 minutes intensity levels. For each intensity level, the package is again rotated evenly across the bottom, side, and end of the package. Furthermore, the shape of the vibration profile has changed, causing different frequency levels to be more pronounced.
The goal of the updated standard is to better represent real world conditions and to provide an improved testing experience.
In Summary:
- Schedule E – Random Vibration
- Truck Profile
- Previous Grms (Each AL run for 60 Minutes total – 20/20/20: Bottom/Side/End)
- Assurance Level 1 – 0.73
- Assurance Level 2 – 0.52
- Assurance Level 3 – 0.37
- New Grms
- High Level – 0.70
- Medium Level – 0.54
- Low Level – 0.40
- Previous Grms (Each AL run for 60 Minutes total – 20/20/20: Bottom/Side/End)
- Truck Profile
Duration on Table for New Truck Profile – Total Table Time 60 Minutes
- Low Level – 40 Minutes (Bottom/Side/End)
- Medium Level – 15 Minutes (Bottom/Side/End)
- High Level – 5 Minutes (Bottom/Side/End)