For Division 2, which design approach is associated with allowing higher allowable stress?

For Division 2, which design approach is associated with allowing higher allowable stress?

• A. Design by rule of thumb
• B. Increased corrosion allowance
• C. Use of higher grade materials
• D. Design by analysis

Answer: (D)

In Division 2, design by analysis is the approach that allows higher allowable stresses. By performing explicit calculations that reflect the actual geometry, loads, and material behavior, you can show that the stresses in the component stay within the code’s allowable limits for those conditions, which often permits a more efficient (less conservative) design. This is in contrast to using rule-of-thumb methods, which rely on conservative, simplified rules and typically result in lower allowable stresses. Increasing corrosion allowance affects thickness to account for material loss, not the allowable stress, and using higher grade materials is a material choice, not the design method itself.

In Division 2, design by analysis is the approach that allows higher allowable stresses. By performing explicit calculations that reflect the actual geometry, loads, and material behavior, you can show that the stresses in the component stay within the code’s allowable limits for those conditions, which often permits a more efficient (less conservative) design. This is in contrast to using rule-of-thumb methods, which rely on conservative, simplified rules and typically result in lower allowable stresses. Increasing corrosion allowance affects thickness to account for material loss, not the allowable stress, and using higher grade materials is a material choice, not the design method itself.