Laserfiche WebLink
4.0 Bed Installation Sizing and Guidelines <br /> Bed Example: <br /> House size: 3 Bedrooms <br /> Design Flow: 450 gpd <br /> Soil Description: 35 mpi <br /> Absorption Field Type: Bed <br /> Distribution Type: Gravity or better <br /> Unit Used: A42 <br /> Calculate Minimum Basal Area Required <br /> Lookup the information required from Table 2: <br /> Percolation Rate Application Rate <br /> (Mpi) (gpd/ft') <br /> 35 0.467 <br /> Absorption Area: Design Flow= Loading Rate x 0.7 <br /> 450 gpd = 0.467 gpd /ft2 x 0.7 = 674.5, round to 675 ft2 <br /> Calculate Minimum Number of Modules Required <br /> Application A42 <br /> Rate Modules per <br /> GPD/ft2 150 gpd <br /> 1.2 6 <br /> <0.8 7 <br /> <0.6 8 <br /> <0.5 9 <br /> <0.4 10 <br /> <0.3 11 <br /> <0.2 12 <br /> 0.1 13 <br /> Number of Bedrooms x Units per Bedroom <br /> A42 Units required <br /> 3 bedrooms x 9 units per bedroom = 27 A42s <br /> A42 Minimum Bed Length <br /> 27 Units =2 Rows = 13.5, round to 14 Mod/Row <br /> 14 Units x 4 ft./unit + 1 ft= 57 ft per Row <br /> Bed Width (Level Installation) <br /> Bed Width = Basal Area Required _ Row Length <br /> A42 Minimum Bed Width <br /> 675 ft2- 57 ft= 11.8, round to 12 ft <br /> Determine Lateral Spacing <br /> Lateral to Lateral Spacing = Bed Width = Number of Rows <br /> A42: 2 Rows <br /> 12 ft_2 rows 6 ft <br /> Lateral to Edge Spacing = Lateral to Lateral Spacing _ 2 <br /> 6ft=2 3ft <br /> 2022 California Design&Installation Manual Page 15 www.eljen.com <br />