NATIONAL BUREAU OF STANDARDS REPORT

9346

PROGRESS REPORT NO. 6

ON

FLUID DYNAMICS OF PLUMBING

by

R. Wv Beausoliel

and

R. S. Wyly

For Use of Sponsor, Project Advisory Committee,

and NBS Staff Only

Not for Publication or Distribution

U. S. DEPARTMENT OF COMMERCE

NATIONAL OUREAO OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

The National Bureau of Standards is a principal focal point in the Federal Government for assur- ing maximum application of the physical and engineering sciences to the advancement of technology

in industry and commerce. Its responsibilities include development and maintenance of the national

standards of measurement, and the provisions of means for making measurements consistent with

those standards; determination of physical constants and properties of materials; development of methods for testing materials, mechanisms, and structures, and making such tests as may be necessarv. particularly for government agencies: cooperation in the establishment of standard practices

for incorporation in codes and specifications; advisory service to government agencies on scientific and technical problems; invention and development ot devices to serve special needs of the Govern- ment; assistance to industry, business, and consumers in the development and acceptance of commercial standards and simplified trade practice recommendations; administration of programs in cooperation with United States business groups and standards organizations for the development

of international standards of practice; and maintenance of a clearinghouse for the collection and

dissemination of scientific, technical, and engineering information. The scope of the Bureau’s

activities is suggested in the following listing of its three Institutes and their organizational units. Institute for Basic Standards. Applied Mathematics. Electricity. Metrology. Mechanics. Heat. Atomic Physics. Physical Chemistry. Laboratory Astrophysics.* Radiation Physics. Radio Standards

Laboratory:* Radio Standards Physics: Radio Standards Engineering. Office of Standard Reference

Data. Institute for Materials Research. Analytical Chemistry. Polymers. Metallurgy. Inorganic Materials. Reactor Radiations. Cryogenics.* Materials Evaluation Laboratory. Office of Standard Refer- ence Materials. Institute for Applied Technology. Building Research. Information Technology. Performance

Test Development. Electronic Instrumentation. Textile and Apparel Technology Center. Technical

Analysis. Office of Weights and Measures. Office of Engineering Standards. Office of Invention and

Innovation. Office of Technical Resources. Clearinghouse for Federal Scientific and Technical

Information.**

•Located at Boulder, Colorado, 80301. “Located at 5285 Port Royal Road, Springfield. Virginia, 22171.
NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT NBS REPORT

42103-40-4212603 9346

June 10, 1966

PROGRESS REPORT NO. 6

ON

FLUID DYNAMICS OF PLUMBING

by

R. W. Beausoliel

and

The National Association of Horae Builders

R. S. Wyly

for

IMPORTANT NOTICE NATIONAL BUREAU OF gress accounting documents intended

for use within the Governmer Approved for public release by the is subjected to additional evaluation

**nv»v vi hi [joii, id iivi aui me u'litc vi me uiicoiui, iiduuiidi Bureau of Standards, Washi Standards and Technology (NIST) by the Government agency for which

the Report has been specific; October 9 ^015 the Report has been specific; 11il copies °P' <or f 'itst own usee.-

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

ABSTRACT

This progress report, the sixth and last in a series, gives results

of various selected hydraulic loadings on a three-bath, three-level test

plumbing system. Trap-seal losses were measured with several venting

arrangements. A limited number of tests were made with detergents or

solids included in the loads.

The results show that the three-level system required more air for

adequate venting than the one-level, slab-on-grade system previously

tested. Also, the inclusion of detergents in some of the test loads

resulted in adverse trap seal performance.

Further experimental work is needed to adequately evaluate the

performance of test systems with vents smaller than customary, using

various loadings. Standardization of test loads is also needed.

CONTI. ...

Page

1. Introduction 1

2. Apparatus 2

3. Procedure 6

4. Results and Discussion 7

5. Conclusion 16

6 Bibliography 19

1 . INTRODUCTION

A 3 bath, 3 level experimental plumbing system was utilized for

the tests made during this reporting period. Plans called for work to

establish minimum diameters and maximum lengths of vents which would

allow proper trap seal performance under practical loading conditions.

Previous work with a 1 bath, slab on grade system showed satisfactory

pneumatic performance of the test system with considerable reduction in

vent diameter below customary sizes with clear water loadings [l]*. In

the 3 level system detergents or solids were used in some of the loadings

for comparison with clear water loadings.

The work plan also called for some further investigation of air

demand on vents as affected by soil or waste stack length, fitting

geometry, and vertical distribution of load in multiple-fixture loads.

However, because of complexities in evaluating the performance of the

3-level test system, and because a portion of the project funds were

applied to a deficit incurred in the previous fiscal year, no work on

air demand was carried out during this reporting period.

It was not expected nor intended that the laboratory work alone

would set a precedent for the use of small -diameter vents. Obviously,

some factors could not be investigated in the laboratory. For example,

possible effects of aging, weathering, corrosion, fouling, and frost

closure are difficult or impracticable to simulate in the laboratory.

These aspects relating to use of unconventional small-size vents can best

* Numbers in brackets refer to the corresponding number in the Bibliography at the end of this report

- 1-
be investigated by a field study. The sponsor has expressed interest in

such a study, and it is understood tha the present time plans for

such installations in various parts of the country are being developed so

that climatic conditions can be included in the long-time field evaluations.

The project was approved by the National Bureau of Standards

under the Grants- in-sIWsd Program as outlined in NBS Report No. 7736. [2]

2 . APPARATUS

The test system is shown in figure 1. For test purposes, the

vents were not interconnected as would normally be done in the field, but

terminated separately. This modification was considered necessary to

simplify the experimental program. It was considered a conservative

approach, since the relief of pneumatic pressure fluctuations from

recirculation between vents which sometimes occurs in interconnected

systems was not available in the test system used here.

• All piping which would normally be below grade was fabricated of

cast-iron service-weight pipe. Above grade, 3 in. soil stacks and 3 in.

vents were of cast iron. The cast-iron soil piping and fittings were of

hub type joined with neoprene gaskets instead of lead-oakum-pitch joints.

In some instances where special fitting types were not available, oakumpitch joints were made. All of the 1-1/2 and 2 in. vents and the branches

to the main building drain and soil stack that were installed in an abovegrade location were fabricated of Schedule 40, galvanized steel pipe

joined by appropriate recessed, screwed, cast-iron drainage fittings.

To meet plumbing code requirements, the building drain was intended to be

fabricated of 3 in. cast-iron soi] pipe as far downstream as the point of

- 2 -
connection to the basement bathroom group. Beyond this point, the

building drain was to be enlarged to 4 in. size. The reason for this

enlargement is dependent on code practice not to discharge over two

water closets into a 3 in. building drain. Due to an inadvertent error

during construction, the 4 in. portion of the building drain was not

extended upstream beyond the laundry group of fixtures; therefore, a

portion of the 3 in. building drain actually served three water closets.

Since the error was not discovered until the installation was ready for

testing, it seemed reasonable first to investigate system performance

with the undersized drain for later comparison with the larger drain.

This section of drain has recently been enlarged to 4 in. diameter.

The system has been designed to discharge into the laboratory building

drain; however, the end of the experimental system is not tied directly

into the laboratory drain but is separated by an air gap. This separation

will assure that the pneumatic pressure at the end of the experimental

drain will be atmospheric.

The two showers were simulated by means of 2 in. cast-iron soil

pipe "P" traps. The floor drain is represented by a 3 in. cast iron soil

pipe "P" trap. Means for introducing water to replenish trap seal loss

in these traps have been provided.

The two back-to-back water closets were joined to the 3 in. soil

stack by 4" x 6" x 161

' closet bends and 3" x 4" double Washington combination Y and 1/8 bends. The water closet on the lower level was joined

to the 3 in. soil stack by a 4" x 3" reducing closet bend and a 3 in.

combination Y and l/8th bend. No attempt was made to cut these closet

bends as done earlier for the one-story test system, since this should

-3-
not significantly affect results. As showr in figure 1, the rest of the

fixtures included a bathtub installed back-to-back with a shower; two

back-to-back lavatories on the upper level and one on the basement level;

and a two- compartment kitchen sink with food-waste disposal unit and a

dishwasher on the intermediate level. The dishwasher was installed with

its own trap and vent. It could have been installed by means of the holein the -head food-waste disposal unit, but the installation with separate

vent was thought to be more severe from the standpoint of load contribution to the drainage system. Obviously, the hole-in-the -head arrangement

would be the more economical arrangement. The laundry fixtures consisted

of a concrete laundry tub and automatic clothes washer, each installed

with a separate trap, stack, and vent. The clothes washer discharged

into its stack by way of a 2 in. standpipe and recessed, screwed, castiron drainage "P" trap. The water supply for the test system consisted

of runs of 1/2 in. I.D. rubber garden hose terminating at the fixtures at

one end and at a pressure-reducing station manifold at the other end.

Because of the lack of sufficient personnel to expeditiously fill and

discharge fixtures, and to observe trap seal losses, it was considered

necessary to automate the experimental system so that all fixtures could

be operated from a central control station. In past experimentation,

persons have often been used for trap seal reading, fixture filling and

discharging. However, contemporary personnel costs and the complexity of

testing the 3 level experimental system suggested that the automation

approach be used. As automated, all fixtures could be filled and discharged

remotely from the central station by one person and the trap seal losses

for all fixtures could be read from this station. The main advantage
of the automation approach, over and above economics, is that no coordination problem existed during the discharge of the fixtures in accordance

with some predetermined loading sequence. Of course, the main disadvantage

was the considerable amount of time consumed in the design, construction,

and debugging of the innovations required.

laboratory building drain permitted the use of soap and artificial solids

representing human fecal matter in test loadings. As a general rule,

previous laboratory investigations of the hydraulics and pneumatics of

plumbing have been carried out at NBS with clean water. In one investigaand 3-in. building drains, artificial solids loadings were employed in

made from a mixture of plastic asbestos and fine wood shavings molded

into cylinders 1-1/2 to 2 in. in diameter and approximately 4-1/2 in.

long. In other tests, paper towels and toilet paper were used. The solids

loadings contributed to clogging in horizontal lines of 2-in. diameter in

some cases, although in most instances the obstructions could be cleared

by repeated discharge of fixtures without additional solids. See

reference [ l] for a discussion of the characteristics of cellulose sponge

bricks 4-1/2 in. long and 1-1/4 in. in cross section which were used in the

present work. See reference [4] for typical fixture fill depths and

discharge rates for all except the laundry tub. This fixture was filled

to 7-1/2 in. above the discharge orifice, giving a volume of 11.2 gal. and

an average discharge rate of 14.0 gpm.

The fact that this system was connected indirectly with the

tion drainage stacks with 2-

some of the tests [3]. In that investigation, simulated faeces were

- 5 -
3 . PROCEDURE

The test procedure was designed to yield data on trap-seal

performance of the system for various load applications and sizes and

lengths of vents. Most of the work was carried out with the 3-in. building

drain extending beyond the point of connection to the basement bathroom

group, as described in Section 2. The fact that a section of the building

drain was incorrectly, 3-in. instead of 4- in. diameter during most of the

testing does not appear important since (a) such tests as have been made

with both 3 and 4 in. diameters for this short section of drain showed no

significant difference in performance, and (b) most of the test loads involved the discharge of not over two water closets, which is the maximum

number of water closets allowed for a 3-in. building drain by the National

Plumbing Code. Initially 50 ft. coils of 1/2-in. I.D. polyethylene tubing

having a 1/16 in. wall were installed on each vent. Each coil assumed the

same diameter (see figures 2 and 3). With these lengths of tubing attached

to the full-size vent standpipes as shown in figures 2 and 3, and with

the atmospheric terminals of the small I.D. tubing sealed, an air test

was applied to the system such that a positive pressure of 2-in. of water

gage was maintained for at least 1 hr. The pressure loss that occurred

during this time was not more than 0.1 in. of water gage. This may have

resulted from cooling effects in the drain. In any case, a leak of such

small proportions would have negligible effect on the over all venting

performance. Upon satisfactory completion of the air test, electric

probes were inserted through the crown of the building drain extending

nearly to the invert at the positions along the drain as shown in figure 1.

These probes were connected to a power supply, a sensitive microammeter, and

- 6 -
a hand-operated rotary switch. By using a stop watch in conjunction with

this apparatus, the times required for the discharge from various combinations of fixtures to arrive at the probe positions in the drain were recorded,

as shown in table 1. This was done so that all of the water from any

particular sequence of fixture discharges could be concentrated approximately

at one position in the building drain, if desired. This load concentration

tended to give the most severe condition. Various loading patterns were

applied to the test system with 50-ft., 1/2-in. I.D. vents closed and

also open. Some of these loadings were repreated with 25-ft. and 1-ft. le

lengths of 1/2-in. I.D. tubing. Loadings were applied in a similar manner

after the installation of a 1-ft. length of schedule 40, galvanized 1-in.

I.D. steel pipe for the main vent, as well as an 18-ft. length of 1-1/4-in.

I.D. pipe of the same material for the main vent, while in both cases

using 25-ft. lengths of 1/2-in. I.D. tubing for all other vents (see

figures 4 and 5) . Trap seal losses were determined for a number of the lo

loadings listed in table 2. Some of these loadings were applied with

artificial solids or detergent inclusions.

The artificial solids were of the type indicated in reference [l].

The detergent loadings consisted of 200 ml of TIDE in the automatic

clothes washing machine, and SWAN in the discharge of the lavatories, bath

tub, and kitchen sink in the loadings involving detergent in these fixtures.

The SWAN was measured in caps full (container cap), a cap full being 8 ml.

4. RESULTS AND DISCUSSION

The work on the 3-level system has progressed through the first

stage of the investigation as originally planned. This stage was concerned

primarily with the determination of an appropriate set of loadings and a -7-
minimum vent diameter or combination of minimum diameters to use in the

second stage. The second stage had been intended as the final and more

thorough aspect of the work upon which this report would have been based,

and was intended as an evaluation of performance as a function of vent

length. Since it became apparent that stage two could not be completed

within the limitations of the investigation, most of the tests were made

with arbitrary vent diameters, the lengths being either limiting extremes

or somewhat representative of lengths required in field Installations.

In the various bar-graph figures showing trap-seal losses, all

data are based on averages from test runs in triplicate, with the 3- in.

building drain extending downstream to the basement laundry group of

fixtures, where it was enlarged to 4-in. diameter. The lack of a bar and

numeral above a fixture designation on the horizontal scale signifies no

trap seal loss for that fixture following application of the indicated load.

Figure 6 shows trap seal loss for various fixtures with 1/2-in.

I.D. tubing vents 1-ft. long on each vent standpipe. This information is

compared with results from the substitution of a 1-ft. length of 1-in. Sch. 40

galvanized steel pipe for the main vent. A test load was applied consisting of the simultaneous discharge of clear water from closet No. 1 and

lavatory No. 1. None of the trap seal losses exceed 1/2-in. The substitutiin of the 1-ft. length of 1-in. galvanized steel pipe for the main

vent showed a marked improvement. Except for water closet No. 3, which had

0.12 in. loss with the 1/2-in. main vent and none after the enlargement of

the main vent, the lower level fixtures did not have any seal losses. As

a general rule, even with the vents sealed, the discharge of clear water

from upstairs fixtures produced negligible loss of trap seal at the basement

level

- 8-
Figure 7 shows trap seal loss for various fixtures with 1/2-in.

I. D. tubing vents 25-ft. long on each vent standpipe. This information

is compared with results from the substitution of 1/2-in. I. D. tubing

vents 1-ft. long on each standpipe. The test load was the clear water

discharge of both compartments of the two compartment kitchen sink. Also

the effects of substituting for the main vent first a 1-ft. length of 1-in.

galvanized steel pipe and next an 18-ft. length of l-l/4in. galvanized

steel pipe are compared on the same plot. The worst loss occurred in the

bathtub trap with the 25-ft. tubing vents (0.76-in. of water). Considerabl

improvement was observed with enlargement of the main vent. The lower

fixtures did not have any trap seal losses with either venting arrangement.

Figure 8 gives similar information to figure 7 except that 1-ft.

lengths of individual vents were not used, and the load was different.

The test load was the clear water discharge of water closet No. 1. It is

seen that with the 1/2-in. vents throughout, four trap seal losses were 1

in. or more and lavatory No. 2 lost almost 2 in. of trap seal. An increase

in main vent size showed a remarkable improvement in trap seal performance

for this particular loading. The magnitude of the seal losses where 1/2-in

I. D. venting was used throughout suggests the unsuitability of using this

size on all individual vents of this system. Again attention is focused

on the fact that very little trap seal loss was encountered on the lower

level (maximum loss 0.18 in. of water from shower trap).

Figure 9 shows trap seal loss from the simultaneous discharge of

all lower level fixtures. This is shown for 25-ft. lengths and 1-ft.

lengths 1/2-in. I. D. tubing vents. Also, the effects of installing

the two larger diameters of main vent are shown. The trap seal losses

-9-
seem exceptionally low for such a heavy loading. Again, improvement of

considerable amount is noted after substituting a larger diameter on the

main vent. It is also interesting to note that relatively little trap

seal loss occurred in the upper level fixture group. This further

confirms the finding from several of the tests described above that clear

water loadings at one end of the system rarely affected trap seals at the

other end.

Figure 10 shows the effect of open and closed vents on the kitchen

group during the discharge of water closet No. 1. The venting consisted

of 1-ft. lengths of 1/2-in. I. D. tubing. It was desired to find out if

the air introduced through short lengths of 1/2-in. tubing vents to the

kitchen group of fixtures would result in an improvement similar to that

resulting from enlargement of the main vent. It is obvious that some

improvement resulted from the additional venting provided by the kitchen

sink vent and dishwasher vent, but in most instances this improvement

was only marginal.

Figure 11 compares the trap seal performance with the three lengths

of 1/2-in. I. D. tubing used during this work. The 50-ft. lengths are

compared in both the open and closed condition. These comparisons are made

only for the discharge of water closet No. 1. Several of the losses for

lengths of 25 and 50 ft. are well beyond 1 in. of water. The system

certainly should be expected to perform well with only the discharge of

one water closet.

Figure 12 shows trap seal losses with clean water and detergent

solution loadings from the two-compartment kitchen sink. The effect of

- 10-
operating the garbage grinder while discharging a detergent solution was

also investigated. These comparisons are made with 1-ft. lengths of 1/2-i

I. D. tubing in place on all vents. The effect of purging the system with

clean water in an attempt to wash out all of the residual suds from the

drain is also shown. The water temperature was 50® C and 16 ml. of SWAN

detergent was added to each sink compartment which contained 1500 ml. of

water. The discharge of clean water caused little or no loss of trap

seal in most instances. The addition of detergent solution to the test

load substantially increased some of the trap seal losses, particularly

for water closet No. 3, and the operating of the garbage grinder in conjunction with the detergent loading substantially increased the trap seal

loss of water closet No. 3. The effect of purging suds from the system

between runs appears to have resulted in an improvement in the trap seal

performance downstream from the sink, and a worsening upstream.

Figure 13 shows the effect of artificial solids inclusion in the

discharge of water closet No. 1. The comparison is made between a clear

water discharge and discharges including one, two, or three solids [ 1]

The venting consisted of 1/2-in. I. B. tubing 1-ft. long on each individi;?

fixture vent standpipe. Little or no practical difference can be seen

between the results of loadings with and without solids nor can much

effect be detected due to the number of solids introduced.

Figure 14 presents data on trap seal losses for the various fixtv

for the following discharge pattern; Water closet No. 1, Lavatory No. 1.

ao.d bathtub simultaneously; followed 5 sec. later by water closet No. 3,

and automatic clothes washing machine simultaneously . This is shown for h

clear water discharge in comparison with a discharge in which 200 ml of

- 11 -
TIDE was included in the automatic washing machine. Addition of detergent

to the test load increased the trap sea A lossas of three fixtures on the

lowest level of the system, but none of these exceeded 5/8-in. Losses

for the fixtures on the upper and intermediate levels were not increased

by the detergent loading. The location of the clothes washing machine

on the most downstream branch of the system near the building sewer may

account for the relatively slight effect of detergent load on fixture

trap seals upstream from the washing machine. Individual vents consisted

of 25-ft. lengths of 1/2-in. I.D. tubing and the main vent was an 18-ft.

length of 1-1/4-in. galvanized steel pipe.

Figure 15 shows the effect of discharging lavatory No. 1 and lavatory No. 2 with clear water and with 8 ml of SWAN in each. Little or no

trap seal loss occurred from the clear water load except for water closet

No. 3, which lost a little over 1/2-in. of seal. The addition of the

detergent increased the losses in some fixtures, but resulted in a smaller

loss for water closet No. 3. As a general rule, in other tests, water

closet No. 3 received the worst seal loss from detergent loadings.

Figure 16 shows the effect of discharging water closet No. 1

and bath tub simultaneously. This was done with clear water and with

SWAN detergent in the tub. The effects from clear water loadings are

compared to those from 16 ml and 48 ml detergent added to the bathtub.

The venting consisted of 25-ft. lengths of 1/2-in. I. D, tubing for all

except the main vent. The main vent was an 18-ft. length of 1-1/4- in.

galvanized steel schedule 40 pipe. Again, all trap seal losses were less

than 1-in. with the clear water loading. The detergent loading yielded

worse results only in the case of water closet No. 3, but here the effect

- 12 -
was drastic. The temperature of the water in the bath tub was approximately

50° C, probably somewhat hotter than would normally be discharged in

service. This may have contributed to excessive suds generation.

All of the above work was done with the 3-in. building drain

extending down to its junction with the basement laundry group, where it

was enlarged to 4-in. diameter. The section of 3-in. drain between the

basement bath group and the laundry group has recently been replaced by a

4-in. diameter section, as required by the National Plumbing Code [5].

Since this modification to the drain, results from the detergent

loading of figure 1 6 have been observed closely to acquire some understanding

of the phenomenon involved in the complete failure of W.C. No. 3 trap.

By inspection it was found that this failure occurred several minutes

after the passage of all water from the system. A 4-ft. length of 2-in.

clear plastic vent pipe extending above W.C. No. 3 permitted observation

of the detergent flowing up into the vent. The pressure generated was such

as to cause the suds to over-flow the vent, and to cause a noticeable

rise in W.C. No. 3 trap seal. This occurred in a clean system which had

been completely purged of residue detergent from preceding tests. Approx.

16 ml of detergent was used in the test loads. The vent sizes were 1-1/2 in.

for individual fixtures, 1-1/4 in. for the main vent, and 2 in. for W.C.

No. 3. It was found that it took many purges with clear water in order to

eliminate all of the detergent from the system, and that the detergent suds

remained in the drain for many hours. For example, these suds were found

to remain in W.C. No. 3 vent for as long as 40 hrs. after the initial

discharge. This suds persistence has been seen by other researchers.

See page 70 of reference [6], A measurement showed that 2000 ml of

- 13 -
detergent foam placed in a large beaker with a diameter of about 10-in.

persisted for only about 3 hrs. The residua consisted of about 100 ml of

liquid. This seems to indicate that the evaporation rate, or decomposition

rate, as you please, may be dependent on the diameter of the container,

and possibly also on contact of suds with the atmosphere and with water.

Some experimentation would be required to adequately describe and explain

this phenomenon.

The only further data taken on the system after drain modification

concerned the clear water discharge of water closet No. 1 and water closet

No. 2 simultaneously, followed by water closet No. 3 five seconds later.

This was performed with full diameter vents on all fixtures except the

water closets. Vent standpipes 1-1/2-in. I.D. and 5-ft. long were used

on the various fixtures and an 18-ft. length of 1-1/4 in. pipe on the main

vent (water closet No. 1 & No. 2 vent). Water closet No. 3 was vented

through a length of 3-in. cast iron reduced to 2-in. During the first

three runs, water closet No. 3 lost 3/4 in. of seal with seal replenishment between runs. This was somewhat surprising; so more runs were taken.

It was found that after the third run, this loss in water closet No. 3 did

not occur. It was found that no trap seal losses took place with an

additional seven runs, either in W.C. No. 3 or in any other fixture. The

occurrence of the initial three losses of seal in water closet No. 3 may

have been caused by residue detergent suds generated during earlier testing

with detergents, although efforts had been made to assure that the system

was cleared of detergent before commencing the latter test. In any case,

the result of the final seven runs Indicated that the system was adequately

vented for the three water closet loading. Preliminary loadings with this

-14-
combination with the 3-in. , non-code section of building drain between

the basement bath and laundry groups had previously shown no trap seal

losses with this venting arrangement. Thus, the performance of the system

with vents, as described above, was satisfactory with a clear water loading

comprising the 3 water closets, both with and without the "non-code" 3-in.

section of building drain.

For comparison, figure 17 shows data for the 3-water closet, clear

water load with 1/2 in. I.D. tubing 25-ft. long for each of the individual

vents, and a 1-1/4 in. steel pipe 18-ft. long for the main vent. The

building drain was 3-in. diameter extending downstream to the basement

laundry group branch, and 4-in. beyond this point. Water closets No. 1 and

No. 2 were discharged simultaneously, followed by W.C. No. 3 either 3, 5,

or 7 seconds later. The results show that a time delay of five seconds

in discharging W.C. No. 3 produced, on the average, a little more severe

load than either 3 or 7 seconds. However, the difference was not striking.

In addition, figure 17 shows that the use of 1/2-in. I. D. tubing for the

individual vents yielded questionable, "borderline" performance with this

load. Thus, additional venting is probably essential for this load which,

however, seems rather unlikely to occur in field service.

Experience over a period of time with full scale experimental

plumbing systems has shown that the discharge of all fixtures simultaneously

does not necessarily yield the greatest trap seal losses. The data of

figure 18 show one example of this. The data were taken under the worst

possible pneumatic condit ion-—all vents sealed. Therefore, it should not

he inferred that the performance obtained was typical of the system with

venting. As shown in the figure, the discharge of one water closet

-15-
resulted in more trap seal loss than all fixtures discharged simultaneously.

One possible explanation for this is the self trap-seal-logg replenishing

characteristic of the discharging fixtures. Also, it is possible that the

interference of colliding streams in some of the horizontal drains may

have prevented the creation of sub-atmospheric pressures adjacent to the

trap seals. It should not be inferred from the above that the discharge

of one fixture was the most severe load that could have been applied, since

no data are shown with intermediate numbers of fixtures between the two

extremes. Possibly some sequence of discharge of all except one or two

fixtures would have yielded the greatest seal losses.

5 . CONCLUSIONS

1. It can be concluded from this work that 1/2-in. I.D. polyethylene

vents used throughout the test system did not yield satisfactory pneumatic performance. Further work might show that, at least for clear

water loads, 1/2-in. or 3/4-in. I.D. vents could be used on certain

fixtures in combination with larger size vents elsewhere in the

system. This possibility was suggested from the results of tests

made on the 3-level system with a 1-1/4 in. main vent in combination

with 1/2-in. individual vents.

2. In the limited amount of work done with solids loading, little effect

of artificial solids inclusions was detected. However, from this

alone it cannot be said that solids loadings do not affect trap seal

performance. While the artificial solids used were believed to

represent one type of a heavy load, it might be desirable to vary the

type of solid material used and include some paper in the W.C. loads.

For instance, toilet paper and baby diapers of the disposable type

-16-
might be tried. British and Swiss investigators have detected

substantial effects from the use of newspaper and paper diapers.

3. The adverse effects due to detergents in some of the tests, particularly

in relation to trap seals of some of the lowest fixtures, indicates

either (a) the detergent test loads used may have been unreasonably

heavy, or (b) the physical arrangement of the test pipework was not

such as to yield the most favorable performance with detergent loads.

It is understood that builders, plumbing inspectors, and engineers

have generally reported little or no detergent foam problems in one

and two family houses. Thus, it seems clear that further study of the

properties of detergent foam and of the detergent phenomenon under

conditions representative of a typical house plumbing drainage system

should be carried out. The following might be studied: (a) attenuation

of sudsing action with dishwashing or laundering, (b) effect of temperature on extent of suds generation, (c) effects of detergent concentration and composition on suds pressure and rate of suds generation, (d)

effect of pipe diameter and rate of suds generation on suds pressure,

(e) persistence of suds as related to size of container (or pipe) and

proximity to liquid or atmosphere, (f) effect of pipe diameter on ease

of entry of suds into a branch drain or vent, and (g) the mechanism

by which negative pressures occur in a suds-choked system subsequent

to cessation of water flow.

4.. From a consideration of experience-based practices and the data obtained

in this study, it seems likely that it would be advantageous to separate

the discharge from detergent using fixtures in houses, such as the

kitchen sink, automatic clothes washing machine, laundry tub, etc.

-17-
from the discharge of other fixtures connecting the waste branch serving

detergent fixtures to the building drain as close as possible to the

building sewer, instead of connecting it to the main stack or to the

building drain near or ahead of other branch drains. This aspect of

piping arrangement should be further investigated. In some instances,

separate drainage of detergent-using fixtures in high-rise buildings,

has been found effective in alleviating detergent "back-up".

5. It would be informative to load field systems with detergent and

observe whether or not there is a tendency for the suds to back up

into certain fixtures, or to cause trap-seal losses. Observation on

"back-up" would be facilitated by removing the water from the idle

fixture traps. For instance, basement water closet seal removal would

allow easy access to the trap way for suds generated in the drain.

Without seal removal, it would be difficult to detect a field system

choked with detergent suds.

6. Further study is needed to establish "reasonable"test loads in small

systems such as installed in one and two-family houses. Standardization

of test loads would be of great value in achieving uniformity of

results between different tests and different laboratories, and would

permit the evaluation of system performance under loadings similar to

service loadings.

- 18 -
6 . BIBLIOGRAPHY

[

1]

Progress Report No. 5 on Fluid Dynamics of Plumbing,

NBS Report No. 9013. [2]

Progress Report No. 1 on Fluid Dynamics of Plumbing,

NBS Report No. 7736.

[3]

Hydraulics and Pneumatics of 2-inch Drainage Stacks,

NBS Report No. 2521.

[4]

Progress Report No. 3 on Fluid Dynamics of Plumbing,

NBS Report No. 8354.

[5]

National Plumbing Code, ASA A40. 8-1955, American Society

of Mechanical Engineers and American Public Health Association.

[6]

Drainage Pipework in Dwellings: Hydraulic Design and Performance,

A.F.E. Wise, Her Majesty's Stationary Office, London, 1957

- 19 -
Table X„ Fixture discharge arrival time at selected

positions in. building drain

Fixture

Discharge Run Time Time Time Time

Pattern A/ no. to to to to

Station Station Station Station

No. 1 No. 2 No. 3 No. 4

secsecsec

sec

A 1 5 10 13 18

A 2 5 10 12 17

A 2 5 10 12 17

B 1 5 10 12 17

C 1 5 11 14 21

c 2 5 9 12 26

c 3 4 8 11 18

D

E 1 5 11 14 23

E 2 5 11 14 22

E 3 4 11 14 22

F 1 5 12 16 24

F 2 6 11 16 24

F 3 5 11 16 23

TP J=/

F

2/

1 7 9 14 28

2 7 14 18 26

3 7 14 19 27

G 1 5 11 14 23

G 2 5 11 14 23

G 3 5 11 14 23

G

U'

1 5 11 14 23

2 5 11 14 23

3 5 11 14 23

—/ See Table 2 for explanation of symbols

With garbage grinder running

3/ Only one run made. Assumed equivalent to pattern "A".

Hi No data taken. Assumed equivalent to "C".
Table 1. (Continued)

Fixture discharge arrival time at selected

positions in building drain

Fixture

Discharge . Pattern —Run

no. Time

to.

Time

to

Time

te

Time

to

Station

No. 1 Station

No. 2 StationNo. 3

Station

No. 4

sec

secsec

sec

H 1 9 18 - 32

H 2 9 18 - 31

H 3 9 17 - 32

I 1 _ _ 5 13.5

I 2

- - 5.5 13.5

I 3

- - 5 13.6

J 1 - - 4.5 13

J 2

- - 4.5 13

J 3

- -- 4.5 13

K 1 - - - 10

X 2

- - - 10

K 3

- - - 10

L 1 _ - - 14

L 2

-- - - 12

L 3

- - - 11

M 1 5 8 10 13

H 2 5 8 10 13

M 3 5 8 10 12.5

N 1 3 6,5 8.5 16.5

N 2 2.5 7.0 9.0 15.0

N 3 2.5 7.0 9.5 17.2

0 1 4 8 10 17

0 2 4 8 10 15

0 3 3.5 7.5 9.5 15.4

p 1 4 8 10 18

p 2 4 8.5 9.5 18.2

p 3 4.5 8.0 10 14.6
Table 1. (Continued)

Fixture discharge arrival time at selected

positions in building drain

Fixture

Discharge

Pattern

Run Time Time Time Time

no. to to to to

Station Station Station Station

No. 1 No. 2 No. 3 No. 4

sec

secsec. sec.

ql/

R 1/

S 1/

T 1 2.5 6.0 8.0 14.0

T 2 2.5 6.5 7.0 11.5

T 3 2.8 6.5 7.5 12.0

U 1 4.5 9.0 12.0 18.0

U 2 4.5 9.0 11.0 18.0

u 3 4.0 8.8 11.0 18.5

U 2/ 1 4 9.5 12.0 22.0

U 2/ 2 4 9.5 12.5 21.0

U 2/ 3

- — •—

V 1/

w 1/

Xl/

Y 5/

Z 1 9.5

z 2

- - 7.5

z 3

- - 7.5

A 1

1 3 6 7.5 14.2

A 1 2 3 5.5 8.0 14.5

A 1 3 3 5.0 8.0 13.5

_5/ No data taken for these patterns
Table 2. Fixture Discharge Pattern Code

(An Explanation of Table 1 Symbols)

SYMBOL PATTERN

A Water closet No. 1

B Water closet No. 2

C Lavatory No. 1

D Lavatory No. 2

E Bathtub

F Kitchen sink compartment No. 1

G Kitchen sink compartment No. 2

H Dish washer

I Water closet No. 3

J Lavatory No. 3

K Wash tub (laundry tub)

L Automatic clothes washer

M Water closet No. 1 & Water closet No. 2 simultaneously

N Lavatory No. 1 & Lavatory No. 2 simultaneously

0 Water closet No. 1 & Lavatory No. 1 simultaneously

P Water closet No. 2 & Bath tub simultaneously

Q Water Closet No. 1, Lavatory No. 1 & Bath tub simultaneously

R Water closet No. 1, Water closet No. 2 & Lavatory No. 1 simultaneous!

S Water closet No. 1, Water closet No. 2, Lavatory No. 1 & Lavatory

No. 2 simultaneously

T Water closetsNo. 1 & No. 2, Lavatories No. 1 & No. 2, and Bath tub

simultaneously

¥ Sink compartments No. 1 & No. 2 (Kitchen sink) simultaneously

V Kitchen sink compartment No. 1 & Dish washer simultaneously
Table 2. (Continued) Fixture Discharge Pattern Code

SYMBOL PATTERN

W Kitchen sink compartment No. 2 & Dish washer simultaneously

X Kitchen sink compartments No. 1 & No. 2 & Dish washer simultaneously

Y Water closet No. 3 & Lavatory No. 3 simultaneously

Z Laundry tub & Automatic clothes washer simultaneously

A-^ Kitchen sink compartments & Dish washer simultaneously, followed

2 seconds later by top floor group simultaneously

Bi All fixtures discharged simultaneously

C;l All basement level fixtures discharged simultaneously

Two compartment kitchen sink and dishwasher simultaneously,

followed 2 seconds later by basement fixtures simultaneously
wf*

r >• h «c m<- 8r<J 2 > © JO« ® OJX jf -

u. « u.

V)

tal

aoS 5 O ^ «

"* 5 * 6 ,

is <4) c

CO *Hc

4-1 •H o £

CO

a)

to Cf} 3 4J O C6 rr5 o >•, a; -3 o

,c

4J 8JL 4-J *o CO o o 4H I

>*

Q

s^ss * 2 Sr

,. tu K o J o J IU0£ tu

wdo

ft

fl P

*H £0 P

’xi ea

<u

CO <30 3 d

CU P 1»**s .a 3 03

«)

G

p oj d.

,-C

G -P

60 8 P.

•H T3 s 01 R

„q 03

p P P

eg CO iC o p p G

JZ

G 3=4

p

a.

G

!>. «w & P <U o P P m 1 P

CO 60 p *0 c G P

*P „Q 03 p E IS e 3 a g G 3

COG t3

R P G G

Qp r=M •R

<0O e P p G

i=4

p e o X

<y

G

p

CO

G

to P

CO

GG

rG & p O

60

R CO

G

H

p P C

fi

G

JZ •H > P

cam

G

JO e N i o •P G •H CO g so P C rP

XZ

G I-H

p 0. eg

'rl E “Q 03

G V'

1—1H

w

G

d 1-4 CO G i E <y h a> h

rH

m ,o

D PJ TO ^ ^ H

<0in3

60

•H

Pp
PIPE

NIPPLE

WITH

Qcf

Figure

2,

Test

vent

installation

details

for

water

closets

using

1/2-in.

I.D.

tubing

50-ft.

long

(The

25-ft.

coil

had

approximately

the

same

radius,

and

the

1-ft.

length

was

installed

without

coiling.
TUBING

INSERTED

INTO

NIPPLE 1

of

to

M4-1 3 I o O J= in -u

-r-l oo S c

•H 'O X> (U 3 -< U t-H • u Q to • C • to C to •H £ I cm .cu

—I ooc

00 <0 c <-• •H

to3 W

iw

to I

0)

CO 0) o X i-H 4Ul o

"O

>H

C

Q> cr

4-1 CO * S CO3 C

CO *G

CO

x &H

4-»

(1)

u e

CD CO x CO uo 0)

co 4-1 Q>U >>> 3 H 4-1 <1) X 4-1 CO6

tHX

O o

*4-4 >Ha

03 cx

r-H CO tH

CO XI

4J CO

<u rC

T3

i—4 c *r4 o o

•H o

4J

CO • t-H LJ

r-H <4H CO 1 4-» m

CO CM C

*rH a) rC

4-J

H

003

4J 00 r-l •I C n

<l»

O

O

H T-H o

<D3

00
-Jb-

<si

O >* P 5 £ : U

t/i

00

Figure

4.

Test

installation

details

for

main

vent

using a

18-ft.

length

of

1-1/4-in.

steel

pipe
Figure

5.

Test

installation

details

for

main

vent

using

a

1-ft.

length

of

1-in.

steel

pipe.
am *m

WMO

’130 'HU

3'HMHS £ 'AVI £ ‘O'M

HSVM‘0

>! EMUS’ >9 I 'HMKS 8 AVI 3 'O’M 1 'O'M

H31WA JO S3H0SMI - SSOl 1V3S dVHX

T

4-1 9 c

cu v; > ; ' c •H

COB

fit 1 3 •* o i 

TO

(U W\

1-4 1—4

CO

4-4

•11 V1 CO • 3 .4 ai t-4 V l-l CU l.Jf co 1-4 0) ‘ ! 3 cu Cu >, o TO 1-4 ; 1 cu 3 Cu ( V 4 3 CO

co 4-1 I—

4-1 CO CU t—

CU , U 3 4-4 4-4 B 3 co 4: •H (U :!

GO > 4-4o V «-* rCO U3 1 H 3 1-4 CO 4-4 *> <u o CU 00 > ;•$ 4-1 3

to 3 <u 3 > O 1—4

oo • 3 4-4 s •H 4-4 7 oo X 1 3 H 3 r-4 /,

•H 4-4 00 o - t vV 1-1 i • CO J3: A co $ 

i—i • «H 3 4-1 a» o M TO

>> to 3 3 i X 00 •H i-4 '&

Cc 1 1 • i-f TO to

0)

X

CN r—4 *| i 4-1 O 1-4 4-4 o w Cu •5

CU 1-4 •• <4-1 CU 1 t ! 44 to 3 o o

4-1

O

X

CO 1-4 *H

X cu 7 ' <0 4-J 4-4 CO 4-4 <0 00 • / CO CO CU 3 1-4 7

<u • CO 4-4 i—l CO • *4

cu >-i -h CO •S

CO CO 4-1 • . A «1 OJ C 4-1 <U '* * 

O i—1 CD *4-4 6 v HUT) 1 co M r-4 CO <:•; * 1-4 1 ,$

CO ••

X

(HMD. • • Hi !• m C co i-t CM 1

CU TO

•i-4 00

1-t $

<0 CO 1-4

1-4

O CO

H i-3 PQ >Vf • vO

'• K'r

cuM $ 3

00

•H I'X

C*4 y.
0.7 Hlim d0 S3H0NI-SS01 1V3S dVHl

CU Xu

0) d

cu o

-r4CUTJ

TD <u d CO

CO p

4-1 co 03

CO 4J »

d

cu CU > CL

»H X cu

• o

03 CO rH u <u <v d <D

<0 d 4-» > 0 CO 00 X) . d <U C

•H rH •r4 00 rH 1

i-l CO i—< CO u

1—1 CO 4H d C O

CU rC

i-i 00 4-1 O d 00

• *H d

00d C/? -D CU P i-H

•iH 4J d • (0 • 4-J

4-1 r4 Q 44

i-l C/5 •

i o M t—

4

-c 4-1

03 o • CO a

fo a) •H 4-1 -d oo 1 CO u CN X

T3 co \ 4-1 a) X i—1 4-1 u 4-1 a 03 4-1 CU

cu *r4 • • o a)

4-1 d o

44 o rC X

co i-l •r4 4-» cu

cu 4-1 60

03 4-1 CO c * CO CO CJ a; t-4 s -i—

i

t-H 03 4-1 03

cu i-l i-l • CO 03 CO 4-1 4-J CO a) d 4H CU o rH <0 | g

I—

l

CJ TO m co M CN C/5 r—

1

CO • • -d

d) 00 cu • 03 d CO rH CN •W d a-o M

CO co d

d O CO H hi W

a)d

P

<30 •H

td

T3

0!

03P

03

CO&

CUCL

•dCL

c

44 . o TD

CU X co

4-1 p

00d CU

(U d

! 1 CU

Es 4J CO 44 -d

1 4-1 00 00 r4 d

cu d 1—4 CO

4-J 4-1 CO 44

4= 1 4-1 r—

1

4-1 4-J Cu CL

CU CU o O

X X

cu CU

CN r-4

CO CO

CO CO

<u (U 6 G

CO CO

C/3 C/5

CO
2.0

ca:

ieei

L=_

F-T

ce:

_ISZ

J 1 J _L ±

aru

m 0) <u • X X

Q) 4J 4J mm tandpip ted

on

sd

for

m irid

CO

p CO

-UI

D

4-1 °H C 4J <U

<D CO CX > ,0 *r-l 28MHS d ex X CO • u r-H £ mi £ 'DM

HSVMQ

mmx

am

a I dMHS z mi \ mi Z DM 1 DM

wo® - ~ d® ^ w o © © © c(1) >

60c

60U

£0 T“

c

<y

X« *H o • o

60 • 0 & •HC g

<DO

4-> >h

Xi 4-1 O

rC

U

CO 0)

4-) ^ 03 ^ & X in

d> 03 U Q) U r—i 0) O

4-1

4-1 4-1 CO O •

to (U HI

qj

a a) •H 4-J

C

a to o

r-H • 'O 0) C

(U 0) *H

C3 *1-1 r-H

4-1O

a> ca 60 o

X< *H

CO 4-1 X -H o u

CO c

«H 0) Q XI

60C 4-1 •H O

-Q 4J

Z) 60

4-1 4J £

60 a) • C rH Q d) • I—I • W 4J • 4-1 • 4J | CJ 44 00

*H I r-H I f-4 cm a \ CO CO

4-1 O- CX 0 0) <0 o a ^ x x u a) a> soC • • <U 7-1 cm

r—

CO CO • CO CO u

4-1 <33 0) 1 g g m co si CM CO C/3

QJ *• rC

<D 60 CX • • • CO C to H CM CO

60

In

CO

CX X>

63 03 U O H i-l

W

0)

PHp

60 Pm JO S3H0NI -SS01 1W3S dVdl
0.3

eru *m

WMO m uid

%'UPAHS ££ *0*M

HSVM‘0

XNISH

anrs 1 ‘feJMHS 3 AVI i ‘AVI Z ’0‘M I 0‘M

n

— o d d

aaivM jo S3honi

—ssoi ivas dvai

CD

d > d • d o

a; •iH 4-', ai co

•rH 6 X

ex 0) X a) CO d 43 d

CO 4-J

4-1 CO CO d CO o £ 4-1 Cd d CD

a)

X ft. > CD •d m a

43

d • O

d

CO • cU cd a> 4J >, cd Cd CD d sd •d 4-J a) CO d a, co > d o o id » bO OJ X CD d d d aj 0) •d

•H CO rH 4-J ( bO 4-J rH CO <fr d 7—

Cfl 9 d 4-J

d

X rH 6 W d ! a) d *d C •d d CO

CD CO •H I d d Cd d X) 60 O CD o cd c Cd d

bO •H o 43 CD bO d vQ 4-J £ d co 3 43 bO

•H 43 4J 4-1

d co

d CJ bO a> 4d

a) CO • C

d 4-J

d •rH

Q ai bO

dX • i- • d o M d a> 43 CO • Cd d

CO at

O 4-J 1 d C Cd 00 • d •H 1 rH d

43 4-1 1 d Cd X CM d i X •rH \ CO as d

OJ Cd rH d 4-J 4-1 4-J O rH 4H a. ft. ft. 0) 0) • • O (D CD a) Cd > d o a u

M-l aj o rC

XX

X

CO i—

•H 4-J a) at CD U 60

CO

d CO

a • • • CO at O 0) d CN d £

•rH rH

CO 6 Cd CO CO CO

at rH •rH • 9 9 m

CO -u 4-J CO rH d «4H CD a) a> ' o i—

0) 1 E 6 S 1—

< X m CO 9 9 H CM C/5 w W rH

CO • • 43

CD bO

a

CO

d CO rH CN1 co -O'

•rH

d

ft.X bO

CO cOd

d

O co

H .41 CQ

(T\

a)dd

bO

•H

In
0.9

to

CDex

•d

ex XI • d

to CO u W C CO

CD> 4-1 d

d

d CD (D a) > a X o

to rH

to rH to i

CO

d

X CD to o X •H 4J 4-1 XJ T3 O

T3 <D rH d X r*H

eg

O «j

r-i eg i X • 4-4 i d o 4-4 i • CO i W £ XI

toO CD

too e d to d o o O

*d

d r—

id

co

d o O • .d d 4J CO o CD UH 4J

4-1 | d

>, « i—

ai XI &

W) >

T3

d

G

u

CD eg ®H >D u CD & X o r—

0 CO

CD o u •• • CO

<4H

dd £ MH <4-1 o CD X $2 O « *r4 ex co • 4-1 o *d w CD M eg XI

CS toO o to d • •d 4-1 'O

CO CO

G C4-I

dd

a)

X •H •d CD CO CO CD 1 4-4 >

CO CO CvJ

d o •d \ CD »d

d 1—

Q rH XI td *d M <5 C/3 I—

CO • • • • X

<D toO 60 ex • • to d G cO i—

Cxi •d *H d

CX xl 4-J toO CO -eg G d d O 0) eg X X > o

0)d3

toO •H

pH
U31VM 30 S3H0NI -SS01 1V3S dVHl

CO x

C

0)>X . O CO

0)

oj co

Jo •r-) 3 co

CO X

O 3

r-H co

CJ 4-J CO x

3 +J

cd 3

0) CO >

4-1 c T—

01 i-H > cd

0-4 o

o ^ o-J

rC u X

u • QJ 60 5 X

3 o

a) 0-1 CO

r-H O 4-1 4

4-J ;n 0) CO X 60

i-4 60

XI CO 3 X

QJ X X QJ

4-1 cj Xi t-H 3 3 3

cj CO 3 CO QJ QJ QJ 0) •H X • • Q) CO CO Co

0-1 X 3 tf) o o O

00 • O

CO 3 Q X w CO CO CO

oj X u X X X

co 4-J M CO C 3 3 3

cd CO CJ Q) QJ 0) a> ?

• X > > > >

CO C X

0) •H • • • • CO CO i X u X X X

CO OJ CN 3 MH X X X

o r-H „ 3 1 i 1 1

1—

u t-0 X o o in 1—

M LO m CM

r-H

CO • • • • X

a) 60 60 CO • • • • CO 3 3 CO r~H CNI cn X •r4 J-j Co X X 60

CO CO 3 3

O <3 3 H X > «

QJ

Oi3

60 •H

Ph
CO

<DOh

•pHcu X

p

CO

C

4) a

44

J-4 COa

a

o

a

o

CO

CD

P

<Dtou

CD

4-» 0) , X

COCDO

O

P

COC

cua)£u

<D rO

CO XI P

3 3

CO U

CO 44 a o

44 P cu

4-J O U X 44 p cu

<D 1—

1

4-> t>0 > a CO J4 0

cu 3 CO

i—

1

4-J Ch 0)

i—

l

1—1 CO a> 4-J *4 O of

>

•r4 O

C

CD 44

4-J CO 44

CO s CO X cu CD c CD iH 0 44 CO

•l4 jC CO 0 CO X

CO O 0) p >> p

CO co g CO CO CO P 4-J 0 V/

•H 4-J n p 44

CO >4-1 <D 00 O

4-J 1—

1

CD a a 00 CO s £ *r4 X

0) P 0 4-J c <D 00 o 6 •i4 CU p 00

$4 t—

1

0 4-J £> p u

CD u u p

4-J • 44 r—

4

CO a

a> 4-J O X 5-4 X 4-4 U CO p (1) a

I CD CO X CD kO • i—

1

4-J 4-J p 44 JC 0} CO P 44 *r4 CO CO 00 £ CD O J4 >> X p to 00 CO

CD •r4 U u X 4-J r£> cO <D <u 44 44 O fH P a) 4-J 00 a a.

Q> CO 4-J • • 1—

1

CU u CD cu 44 P 0 X p CJ 0

44 44 o a. X X

CO o Q •H 44 44 CD cu

4-J 0 O 4-» CO a) M co 0 0 CO 00 a <D CD P CN co

J-l • to to

CO co P 44 U U a CO CO

<13 rC •r4 CO CO CD CO CO CO o | 4-J -c rC 4-J CO to CN P 0 O CO CU cu O •H \ <D CO CO >> a 6

r—

1

Q r—

4

X •«4 •pH CO CO CO M a Q CO CO

i—

1

CO • • •• 42

CD 00 00 P. • • • CO p p CO i-4 CN CO

•r4 *r4 ^4 a x>

co co

44 to p u u o (D_ CO H iJ > «

(1)

00

P4
eni *m

KIMO

HQ ‘Hid

2‘dMHS

£ AVI

£ 'O'M

HSVM'O

>4N!S * >1 ears

I HMHS

Z AVI

I AVI

Z ‘DM

I ‘O'M

a)a

*rHCL -ac

CO Cl

CO

00 XJ c a)

•nl X

X) o

CO CO o w

T 1 Cl

co c

*r-t 00C

CO 0

X) i-H

•fl

• o u

CO 4-1

>>

1 T—

1

60 CU X) r-l G 00

0) Li Cl U CO o • G X <u rs u • • a

CW c CO

4-1 4-1 • o •rl

CO O Q •H T3

• Cl

co CU M CO Li

CO 00 O a)

Li • •r“l Cl

CO CO G 44 CO

QJ X •iTM

1

•i-l CO o 1 Cl

co co CN C Li O *rH \ <u CO Q r—f XI a) M »—! 1-

1

O 1 co •• • • X CU 00 60 CL

co G G CO • •H •»H >-i H 1 CL XJ 00

cfl CO G L G O 0) CO H X > «

O O O

U .-i CM ro

CU

Ci3

oo

H3XVM dO S3H0NI -SSOl 1V3S dVHl
6

0

00

EBi

lh:

ani *m

WMO

aa ana

2'dMHS

£ AVI

£ DM

HSVM'O

>4NIS*>I

enre

1 urns

2 AVI

1 AVI

2 DM

S 'O'M

GO K <0 IO d d d d d odd kj w — o

CO O

-Qu

a)

X

d)§

c<

c

cd>

c

•r4cdB

<0 rC

Cu

co 0) O 0

c 4-4 X 4-J *r4 d) CJ X CO o t—

r-H >

CO CO 1—

B 3 co e

O •H 00 <0 a Cd c a 0 B

•r-H Cd X 4-J X d)

cn r—4 CO rC

TO 2 1—

4-J S B 1—

•H cd c

to CO 4-» 0

cd CO 4= rO e X

u 3 * •H CO o 4J i-H

r—4 rC rH 00 r-H o 4-1 CO e cd

cd 3 0 4-J d PQ O t—

CO

•Hi CO G ^ C • •rH

4-) cd 4-J C - 4-J 4H CO

0) rH r-* 1 C4

00 P^ 0 m •H

*h ^ B CN a

co O -H

4-1 4-1 CO CO rH

0) CD 4-J CO X > <0 C CO

CO C CO 4-J >•> »-3 -H > CO rQ rC

- CJ 00 • X) iH cd c e

(0 • £3 *r4 •H

4J u rQ 1 O • bO 3

<D :2 d 4-J 4-1 —1 1—

4-4 4-C ,C 1 Cd O to Q i—

to co CD 5 M 4H

cd 00 O

!-i to

CO CO CD C rC

<0 X X *H 4-1 cn O DJ 1 00

CO CO O CN c o *H 1—

\ d)

i—

Q 0 rH rH

i—

cd • • • • <0 00 00

CO c a

•H *r4 a -o 4-J cd CO C

5*4 O (0 H X >

rH t—1 ' O r—

coc

*H

rCo

cde

00a

cd£

co

<0 rC

u

<0 X

<000u

co

4-1

• <o

*H X)

<o

4-J 4-4

cd o

S

r—

u

to

a) o

o

U CN X

p.

to > u

00u

CO pa

d31VM dO S3H0NI-SS01 1V3S dVdl <0U

o

00
00

aaiw* jo SBHONi -sscn nv3S aval

c<

<y x:

PU

01u

X 4-1

Cl) £

CD

i—

i

>

r—

1

cd £

•r-4 £ Cd O 6

cuX CD

• Pn cd

CO 5-4 i-h 4-1 CD o »—

•

•H 4J CO £

Cd 4-) o

o > u CO

CO »-5 > r~*

CO 00 '—

I

C CO

C T>

•H <0

, o 4-J £ >> r-i CO •H V-4 £

0 •H u

4-1 4J 4-> o £ Cd 4-4 CD 4-J a) > 1 a cd 00 cd m •r-4 >

J-4 CNI CL. cd 0) i—4

4-J 4-1 CO i—

1

CD O l-l CD rC X £ <D o

CD a) 4—1 cd 00 > CO CD U

cd 00 £ X rC £ £ •H

CD o •H

4J CO r& | 4-J o *T—

1

P £

<D X 4-J \ • • (D m r—

1

£ 00

4-4 CO 1 O u

cd p Q l—

1

•H CD O 4J 4-J CO <D M 4-4 cd 0) CD

cd £ O o 4J X

cd •r4 Cd CO 4-J £ 4-4 4-4

(D r—

1

•H 4-J *r4 O

CO £ | 00 4J £

CO a CN £ £ cd i—4 O •r4 CD CD 0) B

i—

i

CO t—

4

i—

I

X i—

i

M CJ 00

r-l

cd • • •• rC

CD 00 00 a • CO £ £ cd r—

1

CM

•H u

P. X) 4-J 00

cd <0 £ u o (D cd H J > PQ

0)U

3

60
00

d

<

| am m

mm

m °uid

BMHS

£ AVI

£ °D*M

NSVMQ

mis x

eore

S "BMHS

2 AVI

S AVI

E*0”M

I *0*M

x

d

CP>

d

•H

a) x:X

X

a

cuo

X

at

« d

cu d >

o

d

TO X

CU CO

. >1 cd d

43 I—

u o

3 co CO

4-1 d C X

43 o •H <u X cu r-4

CO d 00 r-4 43 co d CO

4-1 o 43 d r—

I—

co

i—l 3 d

6 • -1-4 4-> 43 d CO 4-4 cu cu 1 a • 00 43 U~l •H 43 d d CM a d

<0 43 43

4-1 43 CO r—

43 • CU 43 43 CU 43 X

xl CO d cu cd <u P3 at 43 43 CO >1 > co d

43 d

00 • • X T—

X 1—

d d 00 6

at 0 •H r-4 d X

4-1 o 43 1 X d 00 o d -0- X cu <!•

a) 43 •

at 00 X r—4 d o d X

4-1 4-4 •

1 o i—4 at d

cd o « i—

X X 43

• 43 d at co at H 4-4 cd CU X 1

CO 00 O o 43 CM d • •r4 CO X

CO to d 43 4-4 £ 0 CO

at 43 1-4 43 •i-l cd

CO o | OO 43 d T—

co so CM d d cd 6 at o •l“l "-i. <u CU <u 6

1—

O r-4 i—X X vO CO H O r—

CA

r-4cO » »« 43

a) 00 00 cu • • M d d CO X CNJ ro

•H •H d axi u oc

cd so d d

u O a) eg h d > PQ

U3im JO S3H3N1-SS01 1V3S dVHl |ao P4
am m

E

— [ CUST/

1 -

r m

\~z=

1

' r— 1 ^ j —

,— 1 ^ r

—i— «>

, 1— «s*

i —

r

i ^

r-

-L I I I l l i i i i

l i i I i

„ l • —• • • _• • _* • • • • • — qOOCOOOOO

mm

m yu

2’UMHS

£ AVI

£ ‘0‘M

HSVM‘0

mm°y§

ania

I MHS

Z AVI

1 AVI

Z DM

I ‘0‘M

aiivm 30 S3H0NI -SS01 1V3S dVHl Figure

17.

The

effect

of

varying

the

discharge

timing

in

a

sequence

load.

Loading:

W.C^

&

W.C.

S

simultaneously

followed

by

W.C.

3

t

sec.

later.

Venting:

1/2-in.

I.D.

tubing

vents

25-ft.

long

installed

on

all

vents

except

the

main

vent

An

18-ft.

length

of

1-1/4-in.

steel

pipe

installed

on

the

main

vent.

Bargraph

Identification:
«31W JO S3H0NI - SSOl 1V3S dVHl

Figure

18.

Trap

seal

losses

with

closed

vents.

Bargraph

Identification:

1.

Discharge

of

W.C.j

,

clear

water.

2.

Discharge

of

all

fixtures

simultaneously,

clear

water.