In what scenario would the hand method be preferred over other methods?

The hand method is preferred in scenarios where rapid assessments of supply requirements are necessary. This is because the hand method allows operators to quickly gauge flows and pressure needs without the need for extensive calculations or using more complex formulas. It can be particularly effective in the field when time is critical, such as when first responding to a fire or emergency situation where swift decisions about water supply are essential.

While other methods can provide more detailed and accurate assessments, they often require more time and resources, which may not be available in urgent situations. Thus, the hand method's efficiency for quick evaluations makes it especially suitable for making immediate decisions about supply needs.