1) What is copper-silver ionization (CSI) and how is it used in facilities?

CSI is a non-oxidizing water treatment that releases copper (Cu²⁺) and silver (Ag⁺) ions into building water systems. The ions circulate through potable and utility piping to control microbes across the distribution network, including Legionella in hot-water systems.

2) Where is CSI applied?

CSI is used in hospitals and healthcare facilities, nursing homes, prisons, jails, hotels, large multi-unit buildings, and schools to reduce waterborne pathogen risks while maintaining normal operations.

3) What ion levels are typical, and what are the EPA drinking-water limits?

Typical targets are approximately 0.1–0.8 ppm copper and 30–80 ppb silver. These ranges are below U.S. drinking-water limits of 1.3 ppm copper and 100 ppb silver. Routine monitoring is recommended.

4) How does CSI control microbes and Legionella?

CSI ions interact with bacterial cells: copper weakens the cell wall, while silver causes lysis (cell death). Because the ion residual persists across hot-water loops, CSI supports control at multiple points in the plumbing network, aiding Legionella mitigation.

5) How do you size a CSI system?

Design starts with an engineering site visit and a CSI data sheet. Sizing accounts for water consumption and peak flow, water chemistry, plumbing design, age, and other parameters so the generator can maintain target ion levels across operating conditions.

6) What water chemistry and design factors matter for CSI?

• pH: Neutral range is preferred; CSI has been shown to work at pH > 9.
• Conductivity: Often effective around ~80–1200 µS; very low or very high conductivity may require adjustments to cell spacing or surface area.
• Temperature: CSI performance is suitable for hot-water loops; unlike many oxidants, efficacy is not diminished by higher temperatures.
• Scaling: Hard water can scale the ionization cell; softening or maintenance may be needed.
• Flow & sizing: Systems modulate voltage/electrode surface area to maintain dose over changing flows.
• Corrosion & materials: Deposition corrosion can occur if copper plates are inside piping; pay attention to flow-cell construction to avoid stray-current inefficiencies.
• Chlorides/sulfates: Typically not a major impact on CSI.

7) How is CSI different from oxidizing disinfectants?

• Mode: Non-oxidizing, byproduct-free approach that does not rely on hazardous oxidants.
• Residual behavior: Provides persistent ion residuals through hot-water systems for up to four weeks.
• Temperature: Remains suitable at higher hot-water temperatures where many oxidants dissipate quickly.

8) How are ion levels and system performance monitored?

Ion concentrations (Cu/Ag) should be measured on an ongoing basis. Options range from manual spot testing to inline monitoring. Proper operation and maintenance are essential.

9) Does CSI address Mycobacteria and NTM?

NTM, including Mycobacterium avium, are more resistant than Legionella and generally require longer exposure to copper and silver. CSI may contribute as part of a broader strategy that includes targeted testing and a comprehensive water management plan.

10) Will a CSI installation or Remediation require building evacuation?

CSI installations and remediations typically do not require building evacuation, which is beneficial for continuously occupied facilities.

11) Where can I get CSI literature or request a quote?

Explore the resources below and contact us for details, engineering support, sizing, and pricing:

• CSI Systems Overview (Legionella Control Systems)
• CSI Legionella Experts (Legionella Control Systems)
• CSI Systems (Secondary Disinfection Systems)
• Contact / Quote