Why should test lengths of hose not exceed 300 feet (100 m) in length?

• A. Longer hoses are heavier.
• B. It reduces water pressure.
• C. It wears out hoses faster.
• D. It is difficult to purge air from longer lengths.

Answer: (D)

During hydrostatic testing, you need to fill the hose with water and purge all air to get an accurate, stable test pressure. Shorter hose lengths make it much easier for air to escape completely. When hoses are longer, air can become trapped in pockets and resist full water fill, so those air pockets stay compressed and prevent a true purge. That leads to unreliable pressure readings and an ineffective test. Keeping lengths to a practical limit like 300 feet helps ensure the line can be fully purged and pressurized uniformly. While longer hoses do add weight and cause some friction loss, the key issue here is the difficulty of removing air from longer sections.