Greetings, Soldier
This archive contains information previously posted on the RepWars home page. The reports briefly deal with aspects of various plumbing systems. Some provide additional online resources allowing you to obtain more in-depth information. Others include editable design forms that can be downloaded to aid you in your campaigns.
AIR CHAMBERS
For many years, Plumbing Engineers have specified air chambers for controlling hydraulic shock in water distribution systems.
In practice, they have proven to be less than satisfactory and in many cases worthless. An air chamber can only be effective when properly sized and
as long as it retains its initial charge of air. Within a brief period of time, the air will be depleted and the chamber will become water-logged, causing the air chamber
to become useless. A better method for controlling hydraulic shock is to utilize manufactured shock absorbers which contain a cushion of inert gas
or air within a permanently sealed unit. This type of device provides many years of effective operation. A good online resource related to specifying
and sizing manufactured shock absorbers can be found at the
MANUFACTURED SHOCK ABSORBERS
Manufacturers have provided online information for specifying and sizing shock absorbers (water hammer arrestors).
The Following sites could help you select the proper equipment your project requires
BFP INSTALLATION
Drainage provisions for reduced pressure zone backflow assemblies (RPZ) are not always given proper consideration during the design of plumbing
systems.
CLIENT COORDINATION
When designing additions or renovations to facilities, it is
important to provide materials and equipment that are compatible with the existing installation and
that are preferred by the owner. We have developed a form that will allow your client to easily identify
the items that should be specified within your documents
Form is a rich text file saved as Pmanques.zip (4kb)
DECOMMISSIONING FLOOR DRAINS
Plumbing Engineers involved with renovation projects are often confronted with floor drains that are no longer required within a building area.
ENERGY CODES
Energy codes have existed in many jurisdictions for over 20 years. Due to the present economic and political climate,
more stringent standards and enforcement procedures are being implemented.
The International Energy Conservation Code is considered by many to be a benchmark. The document below lists a few plumbing related
requirements addressed within the 2000 I.E.C.C.
Below are web sites that provide information concerning energy codes:
ELECTRONIC FIXTURES
Many Plumbing Engineers have experienced an increase in client requests to provide automatic
sensor operated faucets and flush valves. This has been driven by a desire to conserve water, improve hygiene and even just to project a high-tech
image. A Plumbing Engineer must be aware of the various types of sensor operated fixtures available and understand how they operate to insure that the
client will be satisfied with the products specified. To review a few pointers related to electronic activated fixtures
ELECTRICAL/PLUMBING COORDINATION
Communicate with the persons designing the Electrical systems of your projects.
This should begin during the early stages and continue as design develops.
The forms below help organize the information that needs to be conveyed.
There are two separate forms available. The first allows you to
identify proposed Plumbing equipment and systems
at the conceptual or schematic phase. The second accomodates detailed input
such as horsepowers, voltages, locations, etc
Forms are rich text files saved as pepcoord.zip (9kb)
ELEVATORS & SPRINKLERS
When a building is required to be totally protected by sprinklers, NFPA Standard
No. 13
requires that sprinklers be provided for all elevator machine rooms and
pits. However,
sprinklers may be omitted at the top of noncombustible hoistways of
passenger elevators when the car
enclosure meets the requirements of ASME A17.1. The sprinkler in the
pit is only required for hydraulic elevators or if oil buffers are present
and the hoistway is of
combustible construction.
Elevator fire protection must comply with NFPA 13, NFPA 70, NFPA 72, and
ANSI/ASME A17.1 or A17.3 as applicable.
When sprinklers are installed in elevator equipment rooms, the electrical power
to the elevator
controller must shut down prior to sprinkler activation. A common method of
doing this is by using
a heat detector to activate an independently controlled shunt trip circuit
breaker when the
temperature in the machine room exceeds the setting of the heat detector.
The detector shall have
both a lower temperature rating and a higher sensitivity (lower Response
Time Index) as compared to the sprinkler.
A sprinkler head rated at 212deg. and a heat detector rated at 135 deg. is
recommended.
Heat detectors used to shut down elevator power prior to sprinkler
operation shall be placed
within 2ft. of each sprinkler head and connected to the fire alarm control
panel.
A smoke detector should also be provided to initiate phase one elevator
recall. This will send cars to the appropriate level prior to electrical power
shut-down.
No sprinkler risers shall be permitted inside any hoistway. Sprinkler branch
lines shall enter hoistways only where a sprinkler is required.
ONLINE INFORMATION
EMERGENCY LEAK PANS
A leak from drainage piping is never a welcome event. It can be unacceptable if this occurs above "sensitive" areas or equipment.
EXISTING PLUMBING SYSTEMS EVALUATION
Evaluating Plumbing Systems within an existing facility can be accomplished in less time and
more thoroughly by preparing a list of items to observe and reviewing available drawings prior to visiting the site.
The following form may help with this task
Form is a rich text file saved as Peval.zip (8kb)
In addition to product descriptions; The following manufacturer sites
offer online engineering information that can help you design various systems :
EXPANSION TANKS
THE NEXT TIME YOU DESIGN A DOMESTIC WATER HEATING SYSTEM, CONSIDER THE
FOLLOWING :
Thermal expansion occurs when water is heated during non-use periods. The
installation of a Pressure Reducing Valve (PRV), Check Valve or Back Flow
Preventer "closes" the water system, leaving water with no room for expansion.
Many local codes now require a closed system, to prevent backflow into the
water main.
Thermal expansion in a closed plumbing system can be damaging, dangerous and
costly. According to the 1993 BOCA Commentary (P1508.7) and the 1997
International Plumbing Code Commentary (607.3), 40 gal. of water heated from
45°F to 145°F will have 1 gal. of thermal expansion, a ratio of 40:1.
EXPANSION TANK PRESSURE
Because of shipping regulations, expansion tanks come pre-charged at only 40 psi. If your system pressure is 40 psi, you can leave it at that.
Otherwise, you should specify that the tank be charged up to the actual system operating pressure BEFORE being installed.
(Charging it after installation will work only if there is no water pressure against it.) This makes the most effective use of the tank.
The bigger the difference between the air pressure in the tank and the actual water pressure, the less effective the tank will be at controlling thermal
expansion.
The following sites contain helpful information concerning
the application of expansion tanks :
PLUMBING FIXTURE CHASES
A basic duty of a Plumbing Engineer is to insure that Architectural floor plans provide sufficient
wall and chase spaces required to properly install various plumbing fixtures.
The following Download may aid you in the coordination of this effort :
Form is a Word Document file saved as pchases.zip (116kb)
ARCHITECTURAL INSTRUCTION
An Architect must have basic knowledge concerning plumbing fixture installation requirements.
Encourage the Architects you work with to review the following information. It is a new installment to the RepWars
"Plumbing for Architects" section and provides explanations and graphics to help them accommodate plumbing fixture
piping and supports
PLUMBING FIXTURE SELECTION
How often has an Architect informed you that a sink, water closet or other
fixture is needed,
but seems to be oblivious and maybe even unconcerned as to exactly what type is
actually required? A new page has been added to help provide an
Architect with basic knowledge concerning fixtures and their selection. This is
an installment to the
"Plumbing for Architects"
section within this site which is intended to inform Architects of various
aspects of Plumbing systems.
Review this new article and forward the address to the Architects you work
with. Your design efforts may be a little easier
if the Architects have an understanding of plumbing components.
PLUMBING FIXTURE MANUFACTURERS
The following sites provide online product information that will help you select Plumbing Fixtures :
GAUGES
Plumbing design documents should clearly define the placement and type of all gauges required to allow proper start-up, commissioning, operational performance and
troubleshooting of systems included within a project.
HOW HOT IS TOO HOT?
Thousands are scalded each year by domestic hot water. Poor system design, improper installation, equipment malfunctions, inadequate system maintenance and
misuse by end users all play a role in the cause.
LEGIONELLA
Though the first Legionella outbreak was ascribed to water from an air-conditioning cooling tower,
most cases are acquired from contamination of potable water supplies. This fact makes it important that Plumbing Engineers address
this issue. Where practicable, the following engineering measures should be incorporated into the design of your systems:
ONLINE RESOURCES CONCERNING LEGIONELLA
LOUVERS
THE NEXT TIME YOU DESIGN A COMBUSTION AIR LOUVER, THIS FREE DOWNLOAD MIGHT
HELP.
The General has created a spreadsheet type program that will size louvers for
you based on the Uniform Plumbing Code. All you have to do is enter
equipment BTU's. It is a template that will allow you to include the project
name, equipment descriptions,
etc., so you can forward it to the architect and include it within your project
design file for reference. If you have Excel '95 or later, Check it out
DOMESTIC WATER HEATERS
The following sites contain helpful information
concerning
the application and selection of water heaters :
NATURAL GAS SERVICE
Most natural gas companies require a formal written request for a new gas service
when desired delivery pressure on the customer side of the meter is 1 p.s.i. or higher. The request must identify type and
btu input of all proposed gas fired equipment. We have developed a template that you may consider using the next time
the need arises. The form provides spaces to list equipment and will automatically total btu's
NEMA ENCLOSURES
Proper enclosures should be specified for all plumbing equipment electrical components.
A Plumbing Engineer must verify the environment where equipment will be located and determine
which enclosure is required to protect personnel from injury and to prevent electrical components from being
affected by dirt, water, ice, snow, oil and other hazards.
NFPA 99 - 2005
The 2005 release of NFPA 99 "Health Care Facilities" has incorporated a few significant changes to the 2002 edition.
Most notably are the allowances for the use of oil-free screw type air compressors and computers as alarm annunciators.
There have also been numerous badly needed clarifications incorporated.
PIPE SUPPORTS
Do not underestimate the importance of providing unambiguous details and specifications for the various pipe and equipment supports
required within your projects. Leaving this aspect of your bid documents up to the imagination of the bidding contractors can
provide you with much embarrassment and possible liability concerns. Insure that proper support methods and spacing is clearly identified within your documents for each type of piping material and equipment.
Consider including information directly on the contract drawings (rather than the specifications) that should be referenced by the individual installing the systems.
This can help insure that your design is followed due to the fact that the installer may not have perpetual access to the specifications.
COPPER PIPE SUPPORTS
Bare copper pipe should always be isolated from supports to reduce sound transmission and/or electrolysis.
Tape wrap is used extensively for this purpose and is approved by various plumbing codes. However, tape wrap is a poor choice
due to the facts that it does not reduce sound transmission and can separate from the pipe because of pipe movement and/or improper installation. Some authorities, such as Hospital Licensing groups, will not accept tape wrap for isolation of medical gas lines from ferrous supports.
Manufactured isolators incorporating clamps with cushion inserts are excellant for this purpose when channel type supports are used. Non-ferrous hangers, such as copper, should be used for single lines and incorporate manufactured isolators to reduce vibration when required.
MANUFACTURED PIPING & EQUIPMENT SUPPORTS
Various manufacturers have provided online information for specifying and sizing Hangers, Guides, Rollers, Roof Curbs, Etc.
The Following sites could help you select the proper supports your project requires
PLUMBING DESIGN PROCESS
Your plumbing design projects will be easier and maintain better quality by following a design process that
organizes the information you need from others and the information you need to give them.
The following form may help with this. It lists what and when basic information is needed and the tasks that the plumbing designer
must accomplish in order to provide outputs to other design diciplines.
ONLINE PLUMBING DETAILS
Various details are available on the web for free downloading. Below are a number of sites that contain details with no charge or registration requirements.
Medical Vacuum and Gases
THE NEXT TIME YOU DESIGN A MEDICAL GAS SYSTEM, CONSIDER THE FOLLOWING
This is obviously not an all inclusive list, but it can help you get started on
the right course. I also recommend spending significant time reading NFPA 99.
ONLINE RESOURCES
The following sites contain helpful information concerning
Medical Vacuum and Gas equipment :
HVAC/PLUMBING COORDINATION
Consistent communication must be maintained between persons designing a project's HVAC and Plumbing
systems. The forms listed below may help with this effort.
There are two separate forms within this download. The first allows you to obtain preliminary information concerning the proposed Mechanical systems
at the conceptual or schematic phase of a project. The second accomodates detailed input from the Mechanical Engineer as system design develops :
ROOF DRAINS
Roof drains must be sized based on local rainfall rates and in accordance with
adopted
local plumbing codes. Tables within plumbing codes list roof drain and pipe
sizes required for various roof areas and rainfall rates.
When designing a system in a location where the rainfall rate is not noted in
the table, the Plumbing Engineer must adjust the values.
In either case, it is good practice to generate documents identifying sizing
requirements and incorporate them into the project's Plumbing Design File.
The Forms below can be used as a guide. Remember to revise the values based on
individual project requirements
MANUFACTURED ROOF DRAINS
The following manufacturers provide online information to aid Plumbing
Engineers in selecting
the proper roof drains for their projects. The J.R. Smith, Zurn, Wade and MIFAB
web sites also include helpful sizing guides
Plumbing Engineers can help themselves by increasing an Architect's knowledge
concerning roof drainage. Applicable information
directed toward Architects can be found by clicking
HERE.
SOUND TRANSMISSION
Sound generated by plumbing system piping and equipment can be annoying and even harmful to building occupants and maintenance personnel.
STEAM
A Plumbing Engineer should have, at least, basic knowledge of steam systems.
This must include; properties of steam, boiler types, emissions, efficiency, and how to calculate demand. Take time to review the following information:
ONLINE STEAM RESOURCES
IPC VERSUS UPC
IAPMO has obtained a copy of an engineering comparison of the two most widely
adopted plumbing codes,
2000 Uniform Plumbing Code and 2000 International Plumbing Code.
This comparison contains a comprehensive analysis of the significant
differences between them
and enables the reader to determine the relative advantages of each
SHUT-OFF VALVES
Price and quality of valves vary significantly. Your specifications should clearly define the performance that your systems require.
If you need domestic water valves that will provide excellent service for many years in commercial and institutional facilities, consider using the following criteria:
ONLINE VALVE INFORMATION
The following manufacturers have provided online information that will aid you in selecting and specifying all types of valves :
VENDORS
ALWAYS MAKE SURE YOU VERIFY ANY INFORMATION OBTAINED FROM VENDORS OR
CONSULTANTS. I had a recent experience with a commercial swimming pool
consultant that confirmed this fact. The pool was to be used for physical
therapy purposes and had wheel chair lifts at various locations to allow
disabled persons to be transported in and out of the pool while sitting in
their chairs. The pool consultant stated that the lifts operated properly
utilizing "City" water pressure and no special system would be required. I
took him for his word because I assumed he knew his trade. Assuming was my mistake.
A few weeks after the facility was occupied, I was informed that the lifts
were not operating properly. I then researched the equipment's requirements on
my own. I found that a minimum 60 p.s.i. water pressure is required for proper
functioning of the lifts. If I had known this during the preparation of my
design documents, I would have included a booster pump and bladder tank system.
We live and learn. Never assume, and never include any information in your design documents that you don't
understand.
THE WAR CONTINUES - Victory depends upon us all working together and acquiring
the information we need. The following assignments can support all of us in our
battles:
RepWars is maintained by persons actively involved in producing drawings and
specifications for Plumbing systems. The objective of this site is to provide an online,
non-biased resource for those striving to produce quality Plumbing Design.
WATER SOFTENERS
THE NEXT TIME YOU DESIGN A WATER SOFTENER SYSTEM, CONSIDER THE FOLLOWING
This is obviously not an all inclusive list, but it can help you get started on
the right course. If you need help sizing or choosing a system, I recommend
that you contact a local water treatment vendor. They can usually provide
helpful information. A good online resource for basic water quality information
can be found
HERE.
SOFTENED WATER
Some Plumbing Engineers and others in our industry hold the belief that softened water
is corrosive to materials. However, recent research has shown this belief to be incorrect.
It's common knowledge that naturally soft water is generally corrosive to plumbing materials, so the assumption has been that water softeners
contribute
to corrosivity in water. Naturally soft groundwater is low in calcium, magnesium, and total dissolved solids (TDS) and usually has a low pH which does
cause it
to be corrosive.
Water softeners exchange sodium for calcium and magnesium and do not change the TDS concentration, pH, and other general water quality
parameters
that are characteristic of naturally soft water. Therefore the softening process does not affect any of the factors which contribute to water corrosivity.
ONLINE RESOURCES - The following sites contain helpful information related to water softener systems :
PLUMBING INFORMATION REQUIRED
Gathering information at the beginning of a project is easier and more thorough
when utilizing
a list of basic items which need to be defined. The following form is not an all inclusive list, but it can help start your own
standard guide :
EDUCATE YOUR ARCHITECTS
Architects are on the front line of most projects you will be involved with. It
is imperative that you consistantly communicate
basic plumbing requirements and concepts enabling them to implement provisions
for your systems.
The following information may aid you in this effort. Encourage the Architects
you work with to review:
FILM PROCESSOR WASTE
Plumbing Engineers often specify a neutralization tank filled with limestone for treating film processor
waste prior to being discharged into the sanitary system with the intention of maintaining code compliant PH levels. However, this design will rarely
produce the results intended. Processors normally discharge a "sludge" or "muddy" type of waste. This waste will coat the limestone,
rendering it ineffective and often prevent drainage.
It is very common to find that maintenance personnel will permanently remove the limestone from tanks to avoid the constant cleaning
and replacement required. It is also very important to note that limestone raises PH levels. If waste Ph is high (Alkaline), limestone treatment will
exaggerate corrosiveness.
SHOWER FLOOR WATERPROOFING
All non-monolithic shower compartment floors should be provided with a waterproof membrane, or "pan", installed beneath the finished shower floor surface,
sloped and secured to the floor drain.
Shower floors installed on ground level slabs are no exception unless the finished shower drain top is at least two inches
below the surrounding finished floor and the shower recess is poured integrally with the adjoining floor.
Approved shower pan materials include PVC, CPE, Sheet Copper and Sheet Lead. PVC and CPE materials are most commonly used due to the
skill, time and expense required for the proper installation of Copper and Lead linings.
SHOWER FLOOR PAN PRODUCTS
LABORATORY WASTE
Non-hazardous lab waste is normally discharged into the sanitary system
after being treated or neutralized, typically for pH correction. Solutions disposed of down the sink must be neutralized between pH6-pH10.
Prior to selecting piping, verify the charactoristivs of the effluent being discharged. There is no single material
that will cover all situations. The most common piping materials specified for lab waste are:
Of the above, the most economical (first cost) piping material is PPFR. However, strong oxidizing acids, organic solvents and chlorinated
hydrocarbons attack a PPFR system. TFE arguably offers the best protection against all chemicals. Only ammonia-based
substances can damage the material. The next best choice is Glass Pipe, which is not acceptable for Ammonium Fluoride, Fluorine, Hydrofluoric Acid,
Hydrofluosilicic Acid and Sodium Sulfide. The remaining mentioned alternatives offer varying degrees of protection.
To view a chart indicating "relative" cost comparison of various lab waste piping,
CLICK HERE
HAZARDOUS WASTE
Certain wastes are regulated as hazardous if they exhibit one or more of the following characteristics:
Ignitability, Reactivity, Corrosivity, or Toxicity.
Sink disposal of any hazardous waste is not permitted by environmental regulations. Wastes exhibiting any of these characteristics must be handled and
disposed of by the facility users in accordance with applicable regulations.
The following is a partial list of waste that CANNOT go down the drain:
The following is a partial list of waste that MAY go down the drain:
Additional information concerning this subject can be reviewed at the following sites:
GALVANIC CORROSION
Galvanic corrosion, often misnamed "electrolysis," is a common form of
corrosion in piping systems. It occurs
when dissimilar metals come into contact with each other. When a galvanic
couple forms, one of the metals
becomes the anode and corrodes faster than it would all by itself, while the
other becomes the cathode and
corrodes slower than it would alone.
The electrochemical difference between metals (when wet) causes
electrons to flow, creating ions. These ions combine with oxygen or other
elements to create corrosion.
PIPE ISOLATORS
Various products are available to help you combat galvanic corrosion. Below are
a few suggestions:
Waterway Fittings:
Nipples, Unions, Flanges:
Channel Isolators:
PIPE PENETRATIONS
A single detail on a set of Plumbing Drawings may not be sufficient to
address all of the various floor pipe penetrations required in a project. Some penetrations will required sleeves and others may not.
All penetrations should be sealed watertight, but some may require sleeves with tops extended above the slab for additional
protection at locations where standing water is expected. A Plumbing Engineer should evaluate the various penetration conditions that will
be encountered on an individual project and clearly define the requirements that must be met within the Contract Documents.
PENETRATION DETAILS
Below are a few floor pipe penetration details that address cast-in-place and cored concrete slabs.
The details are DWG's and can be saved to your PC and/or reviewed on-line if you have a CAD viewer plug-in for your browser or AutoCad R14+ :
VACUUM PUMPS & AIR COMPRESSORS
Selecting the correct vacuum pump or air compressor for a laboratory or medical
facility can be challenging. Manufacturers have developed various types of pumps and compressors to address a wide range of applications.
Rotary vane, liquid ring, reciprocating, screw, lobe, claw, oil-less, lubricated, etc. The Plumbing Engineer must obtain at least a basic understanding
of the various types available and determine which is best suited for a particular project. Facility maintenance personnel experienced with these
systems can be an invaluable resource. Manufacturers' factory technicians and representatives can provide excellent information, but make sure
you filter any biasness they may have concerning the equipment they provide.
EQUIPMENT SELECTION
Based upon observing actual installations of various vacuum pump and
compressed air equipment for many years, lubricated liquid ring (waterless) vacuum pumps and screw type air compressors have proven to provide exceptional
performance and reliability for typical laboratory and medical applications.
Liquid Ring (waterless) Vacuum Pumps:
Rotary Screw Air Compressors:
WATER FREE URINALS
Urinals utilizing "water free" technology have gained surprizingly positive acceptance within the past few years.
These fixtures have demonstrated significant water savings and proven to be acknowledged by many building owners and users as an effective alternative to conventional flushing type urinals.
There are, however, a few very important facts that a Plumbing Engineer should know when considering whether or not to specify them.
BOOSTER PUMPS
There is no single type of domestic water booster system that is suited for every
application. The variables of demand, pressure and usage dictate which type will provide the most practical and efficient operation.
Constant speed motors will operate at maximum load even when system demand is minimal. Variable speed motors operate at variable loads
depending on system demand but are normally only cost effective for relatively large building systems. Facilities t
Failure to provide adequate drainage for RPZ discharge can result in significant property damage.
A Plumbing Engineer should design drainage systems to accommodate testing, draining and relief valve discharges. Drain capacity
must be sized for both intermittent discharges and a catastrophic failure of the relief valve.
Manufacturers flow curves should be used to determine
maximum discharge rate based on anticipated pressures. For additional recommendations for the installation of backflow preventers, review the
document below:
A vague note on a drawing stating " Remove Floor Drain" does not provide the contractor with enough information to properly perform the work required.
Generally, removing a floor drain from an existing slab is impracticable, costly, and can even introduce structural and/or fire rating issues.
For more information concerning this subject and to review/download associated details
Various codes and regulatory agencies address this issue by prohibiting the installation of drains above locations where health and safety may be jepordized.
However, they are not always clear on identifying all areas that are considered "sensitive" nor are they always clear on specifying acceptable methods for protecting these areas when this requirement can not be met.
A Plumbing Engineer should not only become familiar with applicable codes, standards and equipment manufacturer's
requirements; he or she must also thoroughly understand how the various systems are expected to operate.
Using this knowledge, an Engineer can detail, note, and
specify the locations and types of gauges necessary to provide funtional and maintainable installations.
The following provides a few recommendations for plumbing gauge provisions:
Plumbing engineers can help reduce the occurance of scalds by incorporating safeguards in system design, monitoring installations,
specifying quality equipment and educating clients. It is also important to understand what water temperatures can be injurious to end users.
The following article provides information on the potential hazards of hot water and a few recommendations for combating them.
NEMA classifies thirteen different types of enclosures by degree of protection.
The following document provides detailed information that can help you select the appropriate enclosure :
Some jurisdictions will automatically adopt the latest version of an NFPA publication, some will review and eventually adopt them
with exceptions, others may wait for an extended period of time before enforcing an individual edition.
In any case, it is important for a Plumbing Engineer to become familiar with the latest edition of NFPA 99 in order to deal with any confusion
that may arise during design, installation and certification of medical vacuum and gas systems.
To help you understand the latest revisions, Mark Allen with BeaconMedaes has produced the following excellent pamphlet:
Always remember that all details must be modified as required to address particular project requirements before being included within a contract
document.
A Plumbing Engineer should include provisions within design documents to insure that sound is reduced to acceptable levels.
Sound is vibration. The most effective way to limit sound transmission is though the use of isolators. Specify that all piping and motorized equipment
be isolated from direct contact with supports and building elements.
Selecting equipment with reduced decibel ratings will also help. The following table will provide you with a perspective for determining reasonable
sound levels:
For a Plumbing Engineer's perspective, review the following RepWars article