Manufactured as per IS:13488 as well as company standard and available in different sizes and types.
As per company standard
For instance, if we consider 16-4-2-30 to 50-B as a reference then,
16 - Pipe Size (mm)
4 - Emission Rate (LPH)
2 - Class (as per IS:13488)
30 to 50 - Spacing (cm)
B - Uniformity Category
Note: The wall thickness of pipes are based on safe working stress of 2.5 MPa at 20°C. Occasional rise in temperature has no deleterious effect on the life & working pressure of the pipe.