For steam hoses, use fittings designed and intended for steam. EN 14423 standard is the most popular. There are special steam safety clamps made to the same standard, intended for this type of fittings. The fittings permanently crimped with ferrules must not be used for rubber steam hoses. This type of mounting does not allow the clamp to be retightened over the lifespan of the hose, and as the rubber gradually loses its elastic properties, can lead to leakage or even catastrophic rupture of the fitting from the hose. The fittings can be crimped with ferrules only when attached to PTFE hoses. For steel hoses, welded fittings are used.