A haemodialysis patient is exposed to more than 300 litres of water a week through the dialyser membrane. Any impurity in the water (chlorine, aluminium, bacteria, endotoxins) can pass into the blood. That is why dialysis water is one of the most demanding waters there is, far more so than drinking water.
Morocco regularly opens new dialysis centres, including in regions where mains water is hard or brackish. Dialysis centres consult us, for example to replace the membranes of their RO unit.
Quality references
The international reference is the ISO 23500 series of standards. For dialysis water, ISO 23500-3 sets in particular bacterial contamination below 100 CFU/ml and endotoxins below 0.25 EU/ml, with action levels at half these values. For online haemodiafiltration, the dialysis fluid must be "ultrapure" (below 0.1 CFU/ml and 0.03 EU/ml, ISO 23500-5), which requires flawless water upstream. The standard also sets limits for chemical contaminants, including chlorine, aluminium, nitrates and metals.
The treatment chain
- Pretreatment: sand filter, softener to protect the membranes from scale, and above all twin activated carbon filters to remove chlorine and chloramines, which are dangerous for patients.
- Reverse osmosis, preferably double pass: the conductivity of the product water usually drops below a few µS/cm.
- Distribution loop in suitable material, without dead legs, with permanent circulation to the dialysis machines.
- Regular disinfection, thermal or chemical, of the RO unit and the loop, following a written protocol.
Daily checks
- total chlorine test at the outlet of the first carbon filter, before each session;
- monitoring of RO conductivity and pressures, recorded in a log;
- hardness check at the softener outlet;
- bacteriology and endotoxin analyses at regular intervals, by a laboratory.
Maintenance, the key to safety
The membranes of a dialysis RO unit wear out: rising conductivity, falling flow or drifting bacteriology results show it is time to act. Activated carbon must be renewed before it saturates, cartridges changed regularly and the softener resin checked. A preventive maintenance contract, with parts available in Morocco, avoids interrupting sessions.
We can supply membranes compatible with your RO unit, diagnose an existing installation and study the reverse osmosis treatment line of a new centre.
Do you run a dialysis centre? Send us your water analysis or describe your need: our engineers will reply with a technical proposal and a price. Request a quote · Contact us
Sources
- ISO 23500-1, 23500-3 and 23500-5: preparation and quality management of fluids for haemodialysis, water for haemodialysis, quality of dialysis fluid
- European Pharmacopoeia: monograph on water for diluting concentrated haemodialysis solutions
Information article, up to date on 14 November 2026. Your centre's monitoring and disinfection protocols are the responsibility of its medical director and the health authorities.