Closed loop nitrite-based corrosion inhibitor for protection of steel and yellow metals.


  • Formulated to provide corrosion inhibition in closed water systems operating at high and low temperatures, such as engine cooling systems, chilling and L.T.H.W systems and non-portable water storage tanks
  • Inhibits corrosion in closed water systems preventing deposit formations that reduce flow, heat transfer and overall system efficiency
  • Provides effective protection for iron and steel, brass, copper and many other metals that are present in such systems. It is not recommended for use in systems containing aluminum

Typical Properties

  • Appearance: Pink Liquid
  • Odor: Characteristic
  • Solubility in water: Complete
  • pH (as is) @25°C:  > 12
  • Specific Gravity: 1.25 ± 0.05


  • 5 gallon pails
  • 55 gallon non-returnable plastic drums
  • 275 gallon totes and bulk shipments

Safety & Handling

May be toxic by ingestion. Do not take internally. If ingested, drink at least tow (2) glasses of water and get medical attention. Contact with eyes may cause sever irritation or burns. If eyes are contacted, immediately flush with clean water for 15 minutes and then get medical attention. For skin contact, rinse with water for at least 15 minutes. For more information, see the Safety Data Sheet provided with this product.

Chemical Feeding and Control

Effective Nitrite concentrations in system will vary from 500 – 1000 mg/L, depending upon system make-up water and system design. This translates to an initial dosage of 1500 – 3000 mg/L of AWC® A-500. It is recommended that a periodic Nitrite test be performed to ensure that Nitrite levels are within the control limits. It is recommended that AWC® A-500 be dosed into the system via either a bypass feeder or dosing pump, or added when the system is being refilled after draining.  For effective protection of copper, system pH should be in the range of 9 – 9.5 at all times.