Cooper Siver Ionization (CSI)

Copper Silver Ionization (CSI) technologies provide a number of advantages over traditional water treatment options such as thermal eradication or chemical treatments. By generating positively charged copper (Cu2+) and silver (Ag+) ions, CSIDefender® prevents legionella bacteria growth and saturates the biofilm where it grows while reducing the relative cost and technology footprint compared to other solutions.

Our experts can help you choose the right CSI technologies for your project. To find out more, visit our leading Portal-Hub platform.

The chart below lists the advantages and disadvantages of some of the most
common Legionella control and prevention technologies.

Long-Term Legionella Water Treatment Technologies

Copper Silver Ionization (CSI) for Facility Potable Water

ADVANTAGE
  • Ideal for facility point of entry (POE) or Domestic How Water (DHW) loop applications
  • 66% more cost-effective compared to short term technologies
  • Biofilm penetration in 30 to 45 days
  • Up to 75% smaller technology footprint
  • No on-site chemical storage
  • Easy to install using standard plumbing components
  • No corrosion
  • No chemicals
  • No chemical by-product monitoring required (Unlike ClO2)
  • Works in any potable water total dissolved solids (TDS)
  • Works in any potable water pH **
  • No chemical odours
  • No discoloration
  • Works in any liquid water pressures & temperatures, (Unlike PVC or CPVC)
  • Recognized by: The EPA, CDC, WHO, HSE and many other public health authorities
  • Over 20 years on the market worldwide
LIMITATIONS
  • Not intended for cooling towers
  • pH limit of 8.9 as copper starts to precipitate *
  • Premature electrode erosions as some ion chamber cells do not include internal water erosion protection

* In rare high pH environments, organic acids such as acetic or citric can be used to safely lower pH values in potable water and permit the effective use of CSI technologies.

Chloramine (NH2Cl)

ADVANTAGE
  • More “stable” than Cl2 or ClO2
  • Less THM byproduct compared to Cl2
  • Longer residual than Cl2
  • Easy to produce
  • Best pH is 8.3
LIMITATIONS
  • 200X less effective than Cl2
  • Affects dialysis = may cause anemia
  • Limited / No biofilm penetration
  • Limited long-term studies for Legionella
  • Chemical storage (Ammonia & Chlorine)
  • Possible smell of ammonia in water
  • May require periodical switch to Cl2 to prevent biofilm
  • Organic nitrogen competes with ammonia
  • Ammonia overdosing = dichlorimines + nitrogen trichlorides
  • pH determines kind of chloramines (mono, di, tri)

Chlorine Dioxide (ClO2)

ADVANTAGE
  • Less corrosion than Cl2
  • Better performance than Cl2
  • Better performance than super heat & flush
LIMITATIONS
  • ClO2 Must be generated on site
  • Strong odours
  • Reports of plumbing corrosion & damage issues
  • On-site chemical storage
  • Relatively larger technology footprint
  • Service contracts required
  • Requires up to 17 months for Legionella control
  • ClO2 by-products must be monitored
  • ClO2 decomposes by light and heat

Short Term Legionella Remediation for Facility Potable Water Networks

Chlorination (Cl2)

ADVANTAGE
  • Easy to implement
  • Affordable short term Legionella control strategy
  • Comparable results to thermal eradication
  • Can be used in both hot and cold water zones
LIMITATIONS
  • Not discreet to implement
  • Chemical odours
  • Facility potable water shut down and flushing is required
  • No full biofilm saturation
  • No long term Legionella remediation effect
  • Pockets of Cl2 reported in the water pipes causing brown/black water
  • Re-application required every 3 to 5 weeks
  • High labor costs
  • Possible plumbing corrosion

Thermal eradication (AKA Super Heat & Flush)

ADVANTAGE
  • Easy to implement
  • Affordable short term Legionella growth control strategy
LIMITATIONS
  • Limited effects on biofilm where Legionella normally grows
  • Effects only last 3 to 5 weeks
  • Flushing required
  • High risk of scalding
  • Reported plumbing feature damage
  • Impractical for cold water pipes
  • High labor costs

Duality Type Legionella Prevention Facility Water Treatment

UV Lights

ADVANTAGE
  • Treats 100% flowing water
  • No corrosion
  • No by-products
  • Affordable
  • Easy to Install
LIMITATIONS
  • No effect on biofilm where Legionella normally grows
  • Pre-filtration required
  • Lights must be kept clean to work
  • Not considered a systemic Legionella growth control technology

Not Engineered for Legionella Prevention Facility Water Treatment

UV Lights

ADVANTAGE
  • Engineered for swimming pools, fountains, and spas
  • Great for home use
  • Easy to buy
  • Easy to install
  • Very affordable, ($250 to $3,000)
  • Good algae control in pools
LIMITATIONS
  • Known to fail within weeks in potable water applications
  • Not engineered for large daily potable water usage requirements
  • Not approved for potable water
  • Low flow capacity
  • Low silver content
  • No telemetry
  • Limited automation
  • No BMS interface
  • No automation or adaptability to its environment

Legionella Prevention Technology Facts

Design Stage Facility Projects & Copper Silver Ionization:

Engineering consultants should focus on the advantages of long term Legionella prevention water treatment technologies such as copper silver ionisation solutions, keeping in mind that primary city water chlorination treatment levels do not eradicate Legionella or protect facility occupants from preventable Legionella bacteria exposure.