19 Non-metallic building materials; non-metallic rigid pipes for building; asphalt, pitch and bitumen; transportable buildings not of metal; monuments not of metal; non metallic building materials, paving stones; concrete curbstones; concrete sidewalks; rail support, namely, non metallic railway sleepers; manholes, namely, non-electric concrete pipeline installations; technical chambers and tunnels; non-metallic pre-fabricated shelters (civil and military); modular elements for recycling center, namely, underground or semi-underground concrete containers, concrete acoustic screens; concrete and cement blocks; storage vats not of metal; junction boxes not of metal for pipelines; non-metallic building elements of vatting and distribution of surface water and waste water; non metallic drainage slabs, storage partitions; non metallic pits: non-metallic bridges and ledges; prefabricated parts not of metal for cellars; non metallic beams, non metallic joists, non metallic posts, non metallic fences; voussoirs, retaining walls, pedestals, paving, gutter, turf slabs, tree surrounds, supply elements for cisterns and wells, headworks, downspouts, corbeled slabs, manhole meters, columbarium vaults [non metallic constructions]; concrete building elements; building materials of concrete; instrumented concrete structural elements; coverings of concrete; concrete pipes