Compact valve is a self-actuated safety relief device which acts with the aid of a spring assembly that is designed to open at a predetermined pressure. These valves are small version of spring-loaded valves and include conventional, balanced-bellows, and balanced-piston types.

These valves are outside the scope of API 526 standard and are typically smaller compared to API valves. The sizes start from 1/2″x1/2” up to 1 1/2″x1 1/2″. KIASA company offers three different models for various pressure ranges which include NC-230, NC-930, and HP-4090 types.