The United Association of Journeymen and Apprentices of the Plumbing and Pipe Fitting Industry, commonly known as the United Association (UA), is a multi-craft union representing workers in the piping industry. Founded in 1889, it is one of the oldest building trades unions in North America. UA members work across various sectors, primarily in construction and maintenance. Plumbers install, repair, and maintain piping systems in residential, commercial, and industrial settings. This includes water supply, waste removal, and gas systems. Pipefitters specialize in installing and maintaining high-pressure piping systems, often in industrial settings, for materials like steam, chemicals, and fuel. The union also represents sprinkler fitters who install and maintain fire suppression systems. HVAC technicians within the UA work on heating, ventilation, and air conditioning systems. Welders, an integral part of the union, perform specialized welding on pipes and related structures. UA members work in diverse environments, from residential construction to power plants, refineries, and even nuclear facilities. They are involved in major infrastructure projects, including water treatment plants and gas distribution networks. The union places a strong emphasis on training and apprenticeship programs, ensuring its members are skilled in both traditional techniques and emerging technologies. This includes training in computer-aided design, new materials, and energy-efficient systems. The UA advocates for fair wages, workplace safety, and comprehensive benefits for its members across the United States and Canada. It plays a crucial role in maintaining high standards in the piping industry, ensuring the safety and efficiency of vital systems in buildings and infrastructure.