It is common to hear those in the utility industry refer to iron pipe as “C100 pipe” and poly pipe referred to as “C900 pipe”.
The American Water Works Association (AWWA) publishes a very wide variety of recommendations on every aspect of the operation of municipal water works. These are broken down into several major categories. The E category covers water pumps, the F category covers plant equipment, and even the business management of a water department is included in the G category. All of these are available for sale from the AWWA with separate prices for members and non-members.
The one we want to focus on here is the C category which covers water pipes. Each one of these C categories also includes individual manuals on specific aspects of the base category.
In other words, C100 is the code for iron pipe, but within that category, C105 is for “polyethylene encasement for Ductile-Iron pipe”, while C111 is for “rubber gasket joints for Ductile-Iron pipe and fittings”.
C600 is the general code for pipe installation, but within that category, C606 is for “grooved and shouldered joints”, and C621 is for “internal pipe joint seal assemblies for water service”.
