Users can apply antimicrobial spray or coating to the inner surface, the outer surface, or both. It is suitable for a wide range of surfaces, including metals, plastic, glass, fibreglass, stone, ceramics, wood, natural materials, composites and materials, such as roofing materials like tiles and shingles, buildings components and materials like wallboard and siding, concrete products, ceiling tiles, stainless steel, grout mixes and dry concrete, and conveyor and humidifier belts.