# Cargo Floor and Running Load Limits: Structural Protection Calculations

> Learn how to calculate floor-load intensity and running-load limits, and apply shoring techniques to prevent cargo-hold structural damage.

- **Subject:** 031 — Mass and Balance
- **Section:** 031-06 — Cargo Handling
- **Topic code:** 031-06-02
- **Last reviewed:** 2026-04-01
- **Author:** Pablo Asensio Martínez
- **HTML version:** https://pilotsyllabus.com/en/mass-and-balance/cargo-handling/floor-area-load-and-running-load-limitations/

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## Structural Limits
The cargo hold floor is designed to withstand a specific maximum load per unit area. Exceeding this can damage the floor panels or the structure beneath.

### 1. Floor Load Intensity
Defined as the mass per unit area.
$$
\text{Max Load Intensity} = \frac{\text{Mass}}{\text{Contact Area}}
$$
*   **Check**: Ensure calculated intensity $\le$ Max Allowable Intensity ($kg/m^2$ or $lbs/ft^2$).

### 2. Running Load
Defined as the mass per unit length of the cargo hold.
$$
\text{Running Load} = \frac{\text{Mass}}{\text{Length of item}}
$$
*   **Check**: Ensure calculated running load $\le$ Max Allowable Running Load ($kg/m$ or $lbs/in$).
*   Usually critical for long, heavy items.

## Shoring (Spreading the Load)
If a piece of cargo exceeds the floor load intensity limit (e.g., a heavy box with a small base), **shoring** is used to increase the contact area.
*   Placing strict wooden planks or a pallet under the load distributes the weight over a larger area.

$$
\text{Required Area} = \frac{\text{Mass}}{\text{Max Floor Load Limit}}
$$

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