=Defects in Plumbing=
The materials used in house plumbing are many and various, the parts
are very numerous, the joints and connections are frequent, the
position and location of pipes, etc., are often inaccessible and
hidden, and the whole system quite complicated. Moreover, no part of
the house construction is subjected to so many strains and uses, as
well as abuses, as the plumbing of the house. Hence, in no part of
house construction can there be as much bad work and "scamping" done
as in the plumbing; and no part of the house is liable to have so many
defects in construction, maintenance, and condition as the plumbing.
At the same time, the plumbing of a house is of very great importance
and influence on the health of the tenants, for defective materials,
bad workmanship, and improper condition of the plumbing of a house may
endanger the lives of its inhabitants by causing various diseases.
=Defects in Plumbing.=--The defects usually found in plumbing are so
many that they cannot all be enumerated here. Among the principal and
most common defects, however, are the following:
_Materials._--Light-weight iron pipes; these crack easily and cannot
stand the strain of calking. Sand-holes made during casting; these
cannot always be detected, especially when the pipes are tar-coated.
Thin lead pipe; not heavy enough to withstand the bending and drawing
it is subjected to.
_Location and Position._--Pipes may be located within the walls and
built in, in which case they are inaccessible, and may be defective
without anyone being able to discover the defects. Pipes may be laid
with a wrong or an insufficient fall, thus leaving them unflushed, or
retarding the proper velocity of the flow in the pipes. Pipes may be
put underground and have no support underneath, when some parts or
lengths may sink, get out of joint, and the sewage run into the ground
instead of through the pipes. The pipes may be so located as to
require sharp bends and curves, which will retard the flow in them.
_Joints._--Joints in pipes may be defective, leaking, and not
gas-tight because of imperfect calking, insufficient lead having been
used; or, no oakum having been used and the lead running into the
lumen of the pipe; or, not sufficient care and time being taken for
the work. Joints may be defective because of iron ferrules being used
instead of brass ferrules; through improperly wiped joints; through
bad workmanship, bad material, or ignorance of the plumber. Plumbers
often use T branches instead of Y branches; sharp bends instead of
bends of forty-five degrees or more; slip joints instead of
lead-calked ones; also, they often connect a pipe of larger diameter
with a pipe of small diameter, etc.
_Traps._--The traps may be bad in principle and in construction; they
may be badly situated or connected, or they may be easily unsealed,
frequently obstructed, inaccessible, foul, etc.
_Ventilation._--The house drain may have no fresh-air inlet, or the
fresh-air inlet may be obstructed; the vent pipes may be absent, or
obstructed; the vertical pipes may not be extended.
_Condition._--Pipes may have holes, may be badly repaired, bent, out
of shape, or have holes patched up with cement or putty; pipes may be
corroded, gnawed by rats, or they may be obstructed, etc.
The above are only a few of the many defects that may be found in the
plumbing of a house. It is, therefore, of paramount importance to have
the house plumbing regularly, frequently, and thoroughly examined and
inspected, as well as put to the various tests, so as to discover the
defects and remedy them.
=Plumbing Tests.=--The following are a few minor points for testing
plumbing:
(1) To test a trap with a view to finding out whether its seal is lost
or not, knock on the trap with a piece of metal; if the trap is empty,
a hollow sound will be given out; if full, the sound will be dull.
This is not reliable in case the trap is full or half-full with slime,
etc. Another test for the same purpose is as follows: hold a light
near the outlet of the fixture; if the light is drawn in, it is a sign
that the trap is empty.
(2) Defects in leaded joints can be detected if white lead has been
used, as it will be discolored in case sewer gas escape from the
joints.
(3) The connection of a waste pipe of a bath tub with the trap of the
water-closet can sometimes be discovered by suddenly emptying the bath
tub and watching the contents of the water-closet trap; the latter
will be agitated if the waste pipe is discharged into the trap or on
the inlet side of trap of the water-closet.
(4) The presence of sewer gas in a room can be detected by the
following chemical method: saturate a piece of unglazed paper with a
solution of acetate of lead in rain or boiled water, in the proportion
of one to eight; allow the paper to dry, and hang up in the room where
the escape of sewer gas is suspected; if sewer gas is present, the
paper will be completely blackened.
The main tests for plumbing are: (1) the _Hydraulic_ or water-pressure
test; (2) the _Smoke_, or sight test, and (3) the _Scent_, or
peppermint, etc., test.
The _Water-pressure Test_ is used to test the vertical and horizontal
pipes in new plumbing before the fixtures have been connected. It is
applied as follows: the end of the house drain is plugged up with a
proper air-tight plug, of which there are a number on the market. The
pipes are then filled with water to a certain level, which is
carefully noted. The water is allowed to stand in the pipes for half
an hour, at the expiration of which time, if the joints show no sign
of leakage, and are not sweating, and if the level of the water in the
pipes has not fallen, the pipes are water-tight. This is a very
reliable test, and is made obligatory for testing all new plumbing
work.
_The Smoke Test_ is also a very good test. It is applied as follows:
by means of bellows, or some exploding, smoke-producing rocket, smoke
is forced into the system of pipes, the ends plugged up, and the
escape of the smoke watched for, as wherever there are defects in the
pipes the smoke will appear. A number of special appliances for this
test are manufactured, all of them more or less ingenious.
_The Scent Test_ is made by putting into the pipes a certain quantity
of some pungent chemical, like peppermint oil, etc., the odor of which
will escape from the defects in the pipes, if there are any. Oil of
peppermint is commonly used in this country for the test. The
following is the way this test is applied: all the openings of the
pipes on the roof, except one, are closed up tightly with paper, rags,
etc. Into the one open pipe is poured from two to four ounces of
peppermint oil, followed by a pail of hot water, and then the pipe
into which the oil has been put is also plugged up. This is done,
preferably, by an assistant. The inspector then proceeds to slowly
follow the course of the various pipes, and will detect the smell of
the oil wherever it may escape from any defects in the pipes. If the
test is thoroughly and carefully done, if care is taken that no
fixture in the house is used and the traps of same not disturbed
during the test, if the openings of the pipes on the roofs are plugged
up tightly, if the main house trap is not unsealed (otherwise the oil
will escape into the sewer), and if the handling of the oil has been
done by an assistant, so that none adheres to the inspector--if all
these conditions are carried out, the peppermint test is a most
valuable test for the detection of any and all defects in plumbing.
Another precaution to be taken is with regard to the rain leader. If
the rain leader is not trapped, or if its trap is empty, the
peppermint oil may escape from the pipes into the rain leader. Care
must be taken, therefore, that the trap at the base of the rain leader
be sealed; or, if no trap is existing, to close up the connection of
the rain leader with the house drain; or, if this be impossible, to
plug up the opening of the leader near the roof.
Instead of putting the oil into the opening of a pipe on the roof, it
may be put through a fixture on the top floor of the house, although
this is not so satisfactory.
Various appliances have been manufactured to make this test more easy
and accurate. Of the English appliances, the Banner patent drain
grenade, and Kemp's drain tester are worthy of mention. The former
consists "of a thin glass vial charged with pungent and volatile
chemicals. One of the grenades, when dropped down any suitable pipe,
such as the soil pipe, breaks, or the grenade may be inserted through
a trap into the drain, where it is exploded." (Taylor.) Kemp's drain
tester consists of a glass tube containing a chemical with a strong
odor; the tube is fitted with a glass cover, held in place by a string
and a paper band. When the tester is thrown into the pipes and hot
water poured after it, the paper band breaks, the spring opens the
cover, and the contents of the tube fall into the drain.
Recently Dr. W. G. Hudson, an inspector in the Department of Health of
New York, has invented a very ingenious "peppermint cartridge" for
testing plumbing. The invention is, however, not yet manufactured, and
is not on the market.