PPI drugs can be both prescribed and purchased over the counter â in strengths that both cause the same level of damage to the kidneys. Researchers recommend PPIs should be avoided, especially when acid reflux or the like can easily be treated with kidney-safe H2 blockers.
Recommended thickness of concrete slabs. 1  Driveways: 6 - 8 inches (0.15 - 0.2 m). 2  Side walks, barn and granny floors: 5 - 6 inches (0.125 - 0.15 m). 3  Porches, Home garage floors: 4 - 5 inches (0.1 - 0.125 m).
Before calculating how many cubic yards of concrete you need for a slab 20-by-40 feet, you need to add the depth to the equation. The standard depth of a slab is 4 inches or 0.33 feet. You may need to check with your local building inspector to find out what the specific depth of the slab must be in your area.