Question

prohibited fittings & connections review questions

1. the termvertical with reference to piping means departing from true vertical by

________ than ____ degrees.
2 a double y may not be installed in a piping which is ______________

1. a ty installed in a horizontal pipe to receive another horizontal pipe is not

acceptable because waste will run ______ and ______ in the horizontal piping,
and eventually may cause a __________.

1. a double ty, regardless of opening sizes, if installed in a nominally horizontal pipe

will:
a) permit waste to flow upstream in the main drain in which it is installed
b) permit waste from one branch to flow up the opposite branch
c) cause solid waste to catch and build up on the weir of the fitting
d) be quite acceptable

1. a 90° bend installed in drainage piping should not have a radius less than the

diameter of the pipe. a lesser radius is liable to cause a ______________ in the
piping ____________.

1. a galvanized drainage pipe should not be drilled, tapped or welded.

to connect a pipe by those means could:
a) cause blockage
b) reduce the effective diameter of the main pipe
c) result in destruction of the protective coatings
d) cause all of the above

1. vent piping must connect above the flood level rim of the highest fixture to prevent

the ____ piping as acting as a ____ pipe.

1. a 90° short sweep elbow should not be used to change direction from ______

to__________.

1. a double ty may be used if the barrel of the fitting is a minimum of 3 and the

branches are ____, __ or ____ inches.

1. there are ____ ______ restrictions placed on double__
2. there are no restriction placed on tys when installed in __________ piping.
3. list 4 prohibited fittings and explain why each is so.

Explanation:

These questions pertain to plumbing regulations and best - practices. Knowledge of plumbing codes and the behavior of fluids in pipes helps answer them. For example, in question 4, understanding how fittings affect waste flow is key. In question 6, knowledge of the properties of galvanized pipes is needed.

Answer:

1. not more; 15
2. under pressure
3. back; forth; blockage
4. c) cause solid waste to catch and build up on the weir of the fitting
5. blockage; system
6. d) cause all of the above
7. drain; siphon
8. horizontal; vertical
9. 1 - 1/2; 2; 3
10. specific size; TY fittings
11. vertical
12. Examples: 90° short sweep elbow (can cause blockage when changing direction from horizontal to vertical), double Y in under - pressure piping (can lead to improper flow), TY in horizontal pipe to receive another horizontal pipe (waste can run back and forth and cause blockage), galvanized pipe drilled/tapped/welded (can cause blockage, reduce pipe diameter, and damage protective coating).