Brake tubing and hose connections

Brake tubing and hose connections. Brake tubing and hose connections. All connections for air, vacuum, or hydraulic braking systems shall: (1) Be adequate in material and construction to insure proper continued functioning; (2) Be designed, constructed, installed and maintained so as to insure, when properly connected, an attachment free of leaks, constrictions, or other defects; (3) Have suitable provision in every detachable connection to afford reasonable assurance against accidental disconnection; (4) Have the vacuum brake engine manifold connection at least three-eighths inch in diameter.