NEMA 3 is a classification for electrical enclosures defined by the National Electrical Manufacturers Association. It indicates that the enclosure is suitable for outdoor use and can protect against rain, sleet, and snow. NEMA 3 enclosures are designed to prevent the entry of water and dust, making them ideal for various applications in harsh environments. These enclosures are commonly used in industries such as telecommunications, utilities, and manufacturing. They are often made from materials like metal or plastic, ensuring durability and reliability. NEMA 3 ratings help ensure that electrical equipment remains safe and functional in challenging weather conditions.