The question revolves around understanding the building codes related to the live load requirements for partitions in building structures. Here's how we can approach and understand this question:

Step 1: Understand the Concept of Live Load and Partition Load:

• Live Load: This refers to the non-permanent forces or weights that a structure can be expected to support, such as furniture, people, and movable equipment.
• Partition Load: This is a load contributed by partitions that may be rearranged or removed in the future, affecting the structure's live load capacity considerations.

Building codes often specify when partition loads must be considered in addition to live loads. This generally applies if the live load is below a certain threshold.

Step 2: Analyze the Question:

The question is asking for the maximum live load value where partition load still needs to be considered according to building codes. The options provided are: 60 psf, 70 psf, 80 psf, and 90 psf.

Step 3: Rule Out Incorrect Options:

• 60 psf and 70 psf: These are typically lower than the standard threshold for codes that specify when partition loads are to be explicitly considered. As structures often have variable configurations, a broader safety buffer is usually employed.
• 90 psf: This is generally higher than the standard thresholds specified in most building codes. Normally, a limit lower than this would trigger the need for partition load consideration.

Step 4: Verify and Justify the Correct Answer:

The typical threshold stipulated in many building codes is 80 psf, meaning if the live load is less than this value, partition loads must still be accounted for to ensure flexibility and safety of the building's internal spaces.

Conclusion:

Based on the analysis, the correct answer is \(80 \, \text{psf}\). Hence, partitions must be considered if the live load is less than 80 psf, accommodating flexible arrangements and ensuring comprehensive safety design in structures.