- Ha (absolute head or atmospheric in open pits) at sea level and 60 F, Ha is 14.7 psia. At a 3,300-ft elevation and the same temperature, it would be 12.7 psia. And in Denver (5,280-ft elevation) and same the temperature, the value is 11.7 psia. Also, if you have a pressurized tank, you would take the gage pressure and add the local barometric pressure (do not call the weather service; they adjust it for sea level).
- Hst (static head) should be designed for submergence and per NPSH (whichever is greater), but usually sumps are 10- to 20-ft deep with a "typical" water level 1 ft below datum, and a low water level around 4- to 5-ft deep. So, I would suppose that a typical Hst would be 8 ft (3.5 psi) for a 10-ft sump, and 18 ft (7.8 psi) for a vertical turbine pump in an open wet pit.
- The Hfs (friction losses at suction) would be negligible (0.0 psia). So I would venture a typical NPSH
_{A}value for water at sea level and 60 F with a 10-ft sump would be 17.9 psia (41.3 ft) and the 20-ft sump would be 22.2 psia (51.3 ft). - NPSH
_{r}will be obtained from the pump curve and is usually in feet, like I stated in the webcast. If NPSH_{r}is less than NPSH_{A}, you're good to go.

- U.S. Army EM 1110: Military Specification on Sump Design
- British Standard PD CEN/TR 13930
- The book, "Pumping Station Design" by Garr M. Jones and Robert L. Sanks.

- Q = flow in gallons per minute (gpm)
- v = velocity in ft/sec (fps)
- S = submergence or height of liquid level over the suction bell lip in inches
- D
_{b}= outside diameter of suction bell lip in inches - D
_{c }= inside diameter of can in inches - D
_{s}= inside diameter of suction pipe in inches - D
_{x}= largest outside diameter inside the suction can (suction bell, bowls, or column flange) in inches - L
_{s}= length between suction pipe centerline and suction bell lip in inches - L
_{c}= length between suction bell lip and can bottom in inches - L
_{v}= length between the bottom of the vortex suppressor and the can bottom in inches

- Must have a flooded suction pipe and can
- To avoid nonuniform flow within the can, the pump assembly should be centered to within 3% of the suction bell diameter, centerlines ±0.03 × D
_{b} - Allow at least two suction diameters of pipe length to the first component, such as an elbow or valve
- Size suction pipe to a velocity of no more than 6 fps, v = (Q × 0.4085) ÷ D
_{s}^{2} - Allow at least four can diameters between suction centerline and bottom of suction bell lip, L
_{s}≥ 4 × D_{c} - Velocity inside the can should be limited to no greater than 5 fps, v = (Q × 0.4085) ÷ (D
_{c}^{2}- D_{x}^{2}) - Distance between can bottom and suction bell lip should be half the suction bell diameter, L
_{c}= D_{b}÷ 2 - If a vortex suppressor (short basket type) is used, the distance should be 0.125 times the suction bell diameter, L
_{v}= D_{b}÷ 8 - Two guide vanes or straightening vanes the full length of the can beneath the suction and discharge centerlines are recommend at or below 3,000 gpm*
- Straightening vanes in the can are required above 3,000 gpm (per ANSI/HI)*
- Two cross vanes located on the can bottom are recommend at or below 3,000 gpm, and are required above 3,000 gpm (per ANSI/HI)
- Vent the annular area between the can and head inner pipe, likewise between inner pipe and stuffing box
- To limit pre-swirl, consider using straightening vanes in the suction pipe.

- Must have a flooded suction pipe, partially filled can within limits allowed
- To avoid nonuniform flow within the can, the pump assembly should be centered to within 3% of the suction bell diameter, centerlines ± 0.03 × D
_{b} - Allow at least five suction diameters of pipe length to first component such as an elbow, valve, etc.
- Size suction pipe to a velocity of no more than 4 fps, v = (Q × 0.4085) ÷ D
_{s}^{2}** - Allow at least two can diameters between suction centerline and bottom of suction bell lip, L
_{s}≥ 2 × D_{c} - Velocity inside the can should be limited to no greater than 5 fps, v = (Q × 0.4085) ÷ (D
_{c}^{2}- D_{x²}) - Distance between can bottom and suction bell lip should be half the suction bell diameter, L
_{c}= D_{b}÷ 2 - If a vortex suppressor (short basket type) is used the distance should be 0.125 times the suction bell diameter, L
_{v}= D_{b}÷ 8 - Two guide vanes or straightening vanes beneath suction centerline and at 180 deg around (above the fluid level) are recommend at or below 3,000 gpm*
- Straightening vanes in the can are required above 3,000 gpm (per ANSI/HI)*
- At design flow the minimum fluid level should be at least one suction bell diameter above the crown of the suction pipe, S > L
_{s}+ 0.5(D_{s}) + D_{b}** - Two cross vanes located on the can bottom are recommend at or below 3,000 gpm, and are required above 3,000 gpm (per ANSI/HI)
- Vent the annular area between the can and column pipe, likewise between head body pipe and stuffing box
- To limit pre-swirl, consider using straightening vanes in the suction pipe
- Note that in a can pump, can suction losses are not negligible and must be subtracted from NPSH
_{A}(obtain from the pump manufacturer).