Purdue University
Agricultural Extension Service	Mimeo AE 47e
Lafayette, Indiana	November, 1960
LIST OF APPROVED DRAIN TILE MANUFACTURERS By Donald R. Sisson, Extension Agricultural Engineer
High quality drain tile is one of the requirements for a durable, long-lasting tile drainage system. The American Society for Testing Materials (ASTM) has set up specifications for drain tile. Every tile user is urged to purchase only tile meeting these ASTM standards. Two classes or grades of tile are recognized; these are "Standard drain tile" and "extra-quality drain tile." Landowners must use tile of at least "standard" quality to qualify for government incentive payments on tile drainage through the soil conservation program.
A.S.T.M. PHYSICAL TESTS REQUIREMENTS FOR TWO CLASSES OF DRAIN TILE Sizes k to 12 inches diameter, inclusive (Specification C4-55)
Minimum Average
Crushing Strength	Maximum Average Absorption
(3-ecLge Bearing Method) by Five-hour Boiling Test Type of Tile	(lb. per linear foot)	(percent)
	Clay	Concrete	Clay	Concrete
Standard drain tile	800	800	13	10
Extra-quality drain tile	1100	1100	11	8
Other requirements are that the tile be sound and give a clear ring when tapped with a light hammer, that it be about straight in length and circular in cross-section, reasonably smooth on the inside, and free from blisters, checks and cracks that would decrease strength. •
In Indiana, through a cooperative program, a list of approved tile manufacturers is published each May 15 and October 15. Tile manufacturers, the Soil Conservation ervice and Purdue University make this list possible* Each tile manufacturer who Jdres to participate has a strength and absorption test performed on a sample of drain ile during the 90 days preceding the date the list is issued. Technicians of the XI Conservation Service select the samples for test at the manufacturers yard. The Producer transports the tile to the independent laboratory of his choice and pays for e tests. Only manufacturers whose tile meet or surpass the "standard" quality retirements are included on the list. Here is the approved list of manufacturers disputing tile in Indiana as of October 15, i960. This list is effective until a new 11 st is Published about May 15, 1961.