Describe where the chemical is stored and where the pump sits relative to the liquid. The tool sizes storage from the average duty, checks day-tank and bund practice, and calculates NPSH available at the pump suction from the liquid level, suction line losses, acceleration head and vapour pressure.

Enter liquid levels relative to the pump centreline: positive when the liquid is above the pump (flooded suction), negative when the pump lifts (IBC or drum with the pump on top, or a suction lance). Use the lowest operating level for NPSH - that is where priming and cavitation problems start.

Sanity-check: a diaphragm pump on top of an IBC with a lance to the bottom already has around 1 m of lift before pipe losses. Off-gassing chemicals such as sodium hypochlorite should never be lifted.

Choose a pump type and a duty arrangement. The tool works out the rated capacity each pump needs (with a stroke or speed margin from Settings), the turndown each pump must achieve, and compares both with the honest working envelope of that pump type - not just the catalogue extremes.

Turndown is the ratio of the largest to the smallest dose flow. Diaphragm pumps lose accuracy at short stroke lengths, so their reliable turndown is well below the nominal figure. Digital stepper-driven diaphragm pumps hold accuracy over very wide ranges but are limited to modest flows and pressures. Peristaltic pumps are gentle, self-priming and tolerate gas, but slip against high discharge pressures.

A single duty pump with no standby is a process risk on any dose that protects public health - the tool will say so.

Size the discharge line and describe the injection point. The tool calculates peak and mean velocity, friction loss (laminar flow is common with viscous products), the discharge pressure the pump must develop, and whether a pulsation dampener, loading (back-pressure) valve, pressure relief valve, carrier water or heat tracing is needed.

Air locking is the classic dosing-line failure: gas collects at high points and the pump strokes against a compressible pocket. It is worst with off-gassing chemicals, suction lift, long lines and low velocities. The tool scores that risk and suggests the usual remedies.

Carrier water is optional. Enter a carrier flow to see the combined velocity, residence time and dilution at the injection point, plus the compatibility cautions for the chosen chemical.

Tick what your design includes. The tool compares each item with best practice for the chemical, duty and arrangement you have described, and lists anything missing in the Design Review. Modern dosing systems are cabinet-housed, bunded, instrumented for dose confirmation and laid out so that an operator is never exposed to a spray or squirt when changing a container or a pump head.

The materials section shows wetted-material compatibility for the selected chemical and a suggested set for pump heads, seals, valve balls and tubing. Always confirm against the supplier's safety data sheet and the pump manufacturer's compatibility data.

Everything the tool has found, in one place. Critical items are process-risk or safety gaps that should not go to construction unresolved. Check items are worth a second look or a supplier confirmation. Notes are good practice reminders. The design summary table is what goes into the report.

Severity bands are prompts to look, not instructions to act: thresholds live in Settings and should be tuned to your site and the chemical supplier's data.