Marine Portable Water Test Kits

List the parameters the kit must cover, not just “water test kit”. As a minimum ask for free chlorine, total chlorine and pH. WHO also expects electrical conductivity to be measured whenever water is produced on board, since a very low reading shows the remineralisation is not working, and turbidity checks where water quality is in question; add those if the ship makes its own water.^[1]

Make sure the chlorine range reads across the values you will be checking against. WHO guidance puts the chlorine residual ideally between 0.2 and 5 mg/l, at least 0.5 mg/l free chlorine after 30 minutes’ contact at pH below 8.0 for primary disinfection, and at least 0.2 mg/l free chlorine at the point of delivery.^[1]

Ask the supplier for the full contents list, the number of tests the reagents give, and the refill reagent part numbers, so that the reagents can be reordered on their own. WHO notes that monitoring equipment must be calibrated and checked against independent readings and that readings must be recorded, so ask for the calibration or verification method too.^[1]

MLC, 2006 Standard A3.2 paragraph 7 requires frequent documented inspections, by or under the authority of the master, of supplies of food and drinking water and of the spaces and equipment used to store and handle them. A test kit and a logbook of readings are how most ships evidence the drinking-water part.^[2]

WHO’s Guide to Ship Sanitation asks for disinfectant residuals to be monitored throughout the distribution system, including at the farthest tap, and notes that a pH above 8.0 significantly decreases the disinfecting effect of chlorine.^[1]