To combat reference contamination, double junction and/or plasticized references are used to slow down the migration of the sulfide or cyanide to the reference wire. The second junction (IC Controls sensor option – 7) will to increase the path length of the contaminants to the reference wire. The longer the migration path, the longer it will take to reach the reference wire, extending the life of the reference. The second junction also forms a chamber which will slow the migration ions, again extending reference life. A second contamination deterrent is a plasticized reference solution (IC Controls sensor option – 8). The plasticized reference impedes ion migrates as a solid as opposed to a liquid. The more solid the reference solution, the longer contaminant migration will take thus protecting the silver/silver chloride wire.