Rainwater risers on the side walls of residential buildings or factories generally do not need to be installed with inspection ports. Generally, debris is rarely stored or littered on the roof. When it rains, large amounts of rainwater will not be mixed into the water. The sundries that can block the riser. The riser is installed vertically and has basically no slope. It falls into the water very quickly. The greater the density of impurities mixed in the water, the faster it falls. A smaller amount of dust and dead branches cannot block it.
If you are really worried, you can add a simple filter on the top of the riser to block larger debris from entering the riser
1. Drainage vertical Inspection openings should be set up on the pipes, and their spacing should not be greater than 10m. When mechanical clearing is used, it should not be greater than 15m, but they must be set up on the bottom and top floors of the building.
2. The height of the center of the inspection port on the riser from the ground is generally 1.0m, and it forms an angle of 15° with the wall. The center of the inspection port should be 0.15m higher than the upper edge of the sanitary equipment on that layer.
3. If a B-shaped pipe is installed on the riser, an inspection port should be installed on the B-shaped pipe.
4. A cleaning port should be set up at a certain distance on the straight section of the drainage horizontal pipe, and the maximum spacing should comply with the regulations.
5. When there are a large number of sanitary appliances connected to the horizontal drainage pipe, a cleaning port should be provided at the beginning of the horizontal pipe. ① Connect the horizontal drainage pipes of 2 or more toilets. ② Connect the horizontal drainage pipes of 3 or more sanitary appliances.
6. A cleaning port should be provided on the sewage horizontal pipe with a flow angle of less than 135°.