USACE / NAVFAC / AFCESA / NASA UFGS-44 44 73 (April 2006)
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Preparing Activity: USACE Superseding
UFGS-44 44 73 (November 2003)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 44 44 73
ULTRAVIOLET DISINFECTION EQUIPMENT
04/06
NOTE: This guide specification covers the requirements for ultraviolet (UV)
disinfection equipment for treatment of wastewater.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
PART 1 GENERAL
NOTE: This specification should be used to allow the Contractor to install
proven "off-the-shelf" units supplied by reputable vendors. This guide specification
includes technical requirements for ultraviolet disinfection equipment and controls.
This specification will not be used for disinfection of water or industrial
wastes.
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)NEMA 250(2003) Enclosures for Electrical Equipment (1000 Volts Maximum)NEMA C82.4(2002) Ballasts for High-Intensity-Discharge and Low-Pressure Sodium Lamps (Multiple-Supply Type)NEMA ICS 1(2000; R 2005; R 2008) Standard for Industrial Control and Systems General Requirements][NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)NFPA 70(2007; AMD 1 2008) National Electrical Code - 2008 Edition][U.S. ENVIRONMENTAL PROTECTION AGENCY (EPA)EPA 625/1-86/021(1986) Design Manual: Municipal Wastewater Disinfection]1.2 SYSTEM DESCRIPTION
Provide an ultraviolet (UV) disinfection system complete and operational with controls and accessories as shown
and as specified. Provide equipment suitable for outdoor open channel, gravity flow installation including,
but not limited to, the following components, and appurtenances necessary for the interconnection of components,
in the quantities required:
(1) UV lamp module with support rack and bracket.
(2) UV system instrumentation, controls, and power distribution.
(3) Wireway and interconnecting cables.
(4) Water level control device.
(5) UV intensity monitoring system.
(6) Elapsed time meter.
(7) Cleaning system.
(8) Spare parts.
1.2.1 Operation of Existing Facility
NOTE: Include the following paragraph only where UV disinfection system is
replacing another disinfection system at the existing wastewater treatment plant.
Maintain the continuous flow of wastewater and disinfection until the new system is tested, approved and fully
operational. No discharge of untreated wastewater, reduction in existing hydraulic capacity or organic treatment
capacity will be allowed.
1.2.2 Design Conditions
NOTE: Determine or estimate plant flows, total suspended solids (TSS), UV transmittance,
and influent microorganism count. A value for UV transmittance must be determined
from an independent laboratory. Occasionally, a wastewater quality may be encountered
which exceeds the experience of design engineers (e.g. due to an unfamiliar
process design, a familiar but poorly operated process, an under-designed plant,
an unusual influent to the treatment plant, etc.). In these cases, a pilot
study should be conducted to provide information required for design. Channels
must be designed for peak design flow.
Ultraviolet equipment shall disinfect wastewater effluent with the following characteristics:
a. Peak flow, cubic meter per sec. (Mgd): Initial [_____].
Design [_____].
b. Average flow, cu. meter/sec. (Mgd): Initial [_____].
Design [_____].
c. Minimum flow, cu. meter/sec. (Mgd): [_____].
d. Total suspended solids (TSS), mg/L: [_____].
e. Average turbidity, NTU: [_____].
f. UV transmittance @ 253.7 nanometers (nm), through
a 1 cm cell: [_____].
g. Influent [fecal coliform][_____], MPN/100 mL: [_____].
1.2.3 Performance Requirements
NOTE: Typical values for nominal average intensity, UV density and theoretical
retention time are 5100 microwatts per square cm, 3.35 watts per liter, and
7 seconds, respectively. Nominal average intensity will vary between manufacturers.
Density depends upon the design of the particular UV system and the number of
lamp banks. Retention time depends upon the channel geometry and number of
lamp banks. Insert values per specified equipment manufacturer's calculations.
1.2.3.1 Inactivation
NOTE: Predominate effluent criteria used in performance requirements for UV
systems is for whole body contact: 200 most probable number (MPN)/100 ml of
fecal coliforms, with a maximum 7-day average of 400 MPN/100 ml. Some states
have different microbe and disinfection standards; therefore, determine the
site specific disinfection requirements from the state permitting authority.
Provide a system capable of reducing the influent [fecal coliform] [_____] count to [200 MPN/100 mL] [_____]
on a 30 day geometric mean of daily samples.
1.2.3.2 UV Dose
NOTE: Conventional units for UV dosage are microwatt-seconds per square cm.
The standard dosage of UV radiation is determined by the effluent; unfiltered
effluent may require a 30,000 dosage while a dosage of 16,000 to 20,000 is more
typical of filtered effluent to achieve a disinfection safety factor of 2.0.
Insert value per equipment manufacturer's recommendation.
The UV dosage shall be not less than [_____] microwatt-seconds per square cm based on peak design flow conditions,
lamp output at 65 percent of its initial level after 1 year (8750 hours) of lamp operation without fouling on
the lamp sleeves, and minimum UV transmittance as stated in paragraph Design Conditions.
1.2.3.3 Nominal Average Intensity
The nominal average intensity within the channel shall be not less than [_____] microwatts per square cm at a
transmittance of 70 percent after 100 hour burn-in of lamps and with no fouling on the lamp sleeves.
1.2.3.4 UV Density
The UV density of the channel shall be not less than [_____] watts/liter.
1.2.3.5 Retention Time
The actual retention time (t) of the effluent within the system determined by hydraulic analysis shall be not
less than 0.9 times the theoretical retention time (T). The theoretical retention time (T) shall be not less
than [_____] seconds at the peak design flowrate.
1.2.3.6 Plug Flow
The flow characteristics through the system shall closely simulate ideal plug flow conditions under the full
operating flow range. The Morrill Dispersion Index, defined as the time required for 90 percent of the salt
and dye traces to pass, divided by the time required for 10 percent to pass, shall be less than 2.0. The ratio
of the time required for 50 percent of tracer to pass to the mean residence time shall have a value between 0.9
and 1.1. The ratio of the time of initial tracer appearance to the theoretical residence time shall have a value
greater than 0.5.
1.2.3.7 Dispersion
The dispersion coefficient, which accounts for the deviation of the channel's hydraulic behavior from that of
perfect plug flow, shall be less than 100 square cm per second. The dispersion number (ratio of the dispersion
coefficient to the product of flow velocity and channel length) shall be less than 0.l.
1.2.3.8 Turbulence
Flow through the system shall be turbulent with a Reynolds Number greater than 4,000 at average flow.
1.2.3.9 Channel Volume
Full use shall be made of the channel volume throughout the flow range. The ratio of the mean residence time
(theta) to theoretical residence time (T) shall be greater than 0.9.
1.2.3.10 Headloss
The headloss caused by each bank of horizontal lamp modules shall be such that at the peak flow rate no lamp
is exposed to the atmosphere and the maximum depth over the uppermost lamp sleeves is 40 mm 1.5 inch. The headloss
through vertical lamp banks shall not exceed 150 mm 6 inch.
1.2.3.11 Cross Sectional Area
The cross-sectional area occupied by the lamp module frame at the entrance and exit of each bank shall be no
greater than 35 percent of the cross-sectional area occupied by the effluent in the channel.
1.2.3.12 Aspect Ratio
The system shall have a minimum aspect ratio (ratio of channel length to hydraulic radius) of 15 per lamp bank.
1.3 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are for [Contractor Quality Control approval.][information only. When used, a designation following the "G"
designation identifies the office that will review the submittal for the Government.] The following shall be
submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-02 Shop Drawings
Layout[; G][; G, [_____]]
Installation[; G][; G, [_____]]
Drawings showing fabrication methods, assembly, accessories, installation details and point-to-point
wiring diagrams; instrumentation and controls; equipment; dimensions; make and model; materials
of construction; and installation instructions. Drawings shall indicate clearances required
for maintenance and operation and shall also contain complete wiring and schematic diagrams,
equipment layout, dimensions, templates and directions for the installation of anchor bolts
and other anchorages and any other details required to demonstrate that the system has been
coordinated and will properly function as a unit.
SD-03 Product Data
Equipment[; G][; G, [_____]]
Manufacturer's descriptive data, technical literature, and catalog cuts. Submittal shall
include: design calculations relevant to the type of system proposed indicating removal performance
including dose; nominal average intensity within each reactor; UV density; theoretical retention
time of effluent within the system; dispersion coefficient; maximum headloss caused by each
bank of lamp modules; lamp module cross-sectional area; aspect ratio of lamp bank; installation
list; manufacturer's illustrations; and a statement by the equipment manufacturer listing any
exception to or deviations from the contract drawings and specifications.
Framed Instructions
Proposed diagrams, instructions, and other sheets, prior to posting.
Field Training[; G][; G, [_____]]
A proposed lesson plan of field instruction, 30 days prior to commencement of scheduled training.
Spare Parts
Parts list including recommended spare parts and maintenance supplies with current unit prices
and source of supply for each item of operable equipment. List shall include parts recommended
by the manufacturer to be replaced after 1 and 3 years of service. List special tools, instruments,
accessories, and special lifting and handling devices required for periodic maintenance, repair,
adjustment, and calibration.
SD-06 Test Reports.
Design Conditions
a. Results of tests done by an independent testing laboratory showing effective hydraulic
design of the reactor, including headloss calculations.
b. Documentation showing that the type of ballast required for the particular lamp supplied
for the system have performed successfully for a period of not less than one year.
c. Hydraulic calculations demonstrating compliance with the specified hydraulic characteristics.
d. Residence time distribution (RTD) data plotted as concentration versus time, and as cumulative
tracer passed versus time in accordance with EPA 625/1-86/021. The Contracting Officer reserves
the right to require separate tests to be conducted on a system identical in design to the proposed
system if the hydraulic test data submitted by the manufacturer is determined to be unacceptable.
e. The results of a bioassay test done on a scaled model of the full size system by an independent
and certified laboratory shall be submitted to the Contracting Officer. The bioassay results
shall be used to verify the theoretical calculations only and shall be conducted in accordance
with Section 7.3.3.1 of EPA 625/1-86/021. The test protocol and results shall have been certified
by the laboratory which conducted the testing. Tests performed on similar equipment designs
of another manufacturer shall not be acceptable.
f. The test unit used in the development of the RTD curves and bioassay test shall have had
a minimum of 20 lamps utilizing the same lamps, electronic lamp controller, ballast and automatic
level controller as that proposed in the full scale system.
Operating Test
Report in booklet form, upon completion of testing of the installed system. Test report shall
include field tests performed to adjust each component and field tests conducted to prove compliance
with the specified performance criteria. Test report shall indicate the final position of controls.
Site Visits
A written report of the results of each visit by the manufacturer's representative, including
purpose and time of visit, tasks performed and results obtained.
SD-07 Certificates
Manufacturer's Qualifications
Standard Products
Written evidence that equipment and accessories are products of a qualified and experienced
manufacturer.
Performance Testing
Certificate of compliance, as specified.
SD-10 Operation and Maintenance Data.
Operating Instructions[; G][; G, [_____]]
[Six] [_____] complete copies of operating instructions outlining the step-by-step procedures
required for system startup, normal operation, short- and long-term deactivation, and shutdown.
An introduction and overall equipment description, purpose, functions, and simplified theory
of operation shall be included in the beginning of the instructions. Instructions shall include
the manufacturer's name, model number, service manual, parts list, and brief description of
each piece of equipment and its basic operating features. Instructions shall include component
layouts, simplified wiring, and control diagrams for the system as installed. Performance test
data shall be reflected in the operating instructions.
[Six] [_____] complete copies of maintenance instructions listing routine maintenance procedures,
calibration procedures, possible breakdowns and repairs and trouble shooting guides, prior to
the start of the training course.
Each manual shall have an index listing the contents and tab separators between sections.
Manuals shall be bound in sturdy three-ring, loose-leaf binders.
1.4 QUALITY ASSURANCE
1.4.1 Contractor Qualifications
Contractor shall have a minimum of [2] [_____] years experience in the construction of water, wastewater, and/or
industrial wastewater facilities.
1.4.2 Manufacturer's Qualifications
Manufacturer shall have experience in the production of substantially similar equipment, and shall show evidence
of satisfactory operation of identical equipment to that proposed in at least 3 installations for a period not
less than one year disinfecting secondary effluent with similar effluent flow and characteristics to the treatment
plant in this contract.
1.4.3 Equipment Parts
Parts shall be manufactured to standard sizes and gauges so that repair parts furnished at any time can be installed
in the field. Like parts of duplicate units shall be interchangeable.
1.4.4 System Performance
The installed UV system shall produce an effluent which meets the bacteriological requirements of this specification.
The effluent quality exiting the system shall be equal to or better than the specification requirement.
1.5 PRECONSTRUCTION CONFERENCE
Preinstallation conference will be required by the Contracting Officer. Include subContractors, suppliers, and
UV equipment manufacturer.
1.6 DELIVERY, STORAGE, AND HANDLING
Protect from damage, deterioration, weather, excessive humidity, excessive temperature variation, dirt, dust,
and contaminants equipment and materials delivered, handled, and placed in storage, from the time of shipment
until installation is completed and the equipment and materials are ready for operation. Equipment shall be
marked and stored to permit easy identification and inspection. Each item of the equipment shall be tagged or
marked as identified in the delivery schedule or on the shop drawings. Include with each shipment complete packing
lists and bills of materials.
1.7 EXTRA MATERIALS
Spare parts shall be new, exact replacements, and separately packaged. Include with the package bill of materials
with quantity, item description, and part number. Furnish the following spare parts and safety equipment:
a. One completely assembled lamp module.
b. Ten percent of the total number of the syatem lamps.
c. Five percent of the total number of the system ballasts.
d. Ten percent of the total number of the system lamp sleeves.
e. Ten sets of lamp end seals.
f. Ten sets of lamp socket connectors.
g. [Four] [_____] personnel safety shields which block out UV wavelengths between 200 and 400 nm.
PART 2 PRODUCTS
2.1 MATERIALS
Metal in contact with plant effluent shall be either Type 316 or Type 304 stainless steel, passivated. Wiring
which may be exposed to UV light shall be of a material that resists degradation by UV light. Material exposed
to UV light shall be stainless steel, passivated; quartz; polytetrafluoroethylene or other UV resistant material.
2.1.1 Standard Products
Provide material and equipment which are the standard product of a manufacturer regularly engaged in the manufacture
of the product and which essentially duplicate equipment that has been in satisfactory operation for at least
2 years prior to bid opening. Equipment shall be supported by a service organization that is, in the opinion
of the Contracting Officer, reasonably convenient to the site.
2.1.2 Nameplates
Provide major equipment items with the manufacturer's name, address, type or style, model or serial number, and
catalog number on a plate secured to the item of equipment.
2.2 EQUIPMENT
2.2.1 Layout
The physical layout of the system shown is based on equipment manufactured by [_____]. If UV equipment proposed
is sufficiently different than that shown, submit detailed, modified layout drawings and descriptions for approval
by the Contracting Officer within 5 working days following Notice to Proceed. Also obtain approval, if applicable,
from the State permitting authority for the sufficiently different equipment and layout proposed within [15]
[_____] working days following Notice to Proceed.
2.2.2 Equipment Construction
2.2.2.1 UV Lamp Module
a. Module shall consist of lamps with each lamp placed in an individual sleeve. Module shall be capable
of being withdrawn as a unit and replaced without interrupting operation of any other module, shall be
self-supporting in the channel, and shall be capable of supporting a weight of 90 kg 200 pounds.
b. Horizontal lamp module shall have lamps in sleeves sealed and supported in a NEMA 6P stainless steel
frame. Electrical wires which carry power to the lamps and ballasts shall be completely enclosed in
the frame and shall be isolated from the wastewater. The frame shall be capable of protecting lamps
and sleeves from foreign material or debris within the channel.
c. Vertically oriented module shall have lamps installed in a weatherproof, watertight enclosure. Sleeve
shall be fitted to the enclosure using compression fitting and neoprene gasket. Wiring shall have numbered
terminal strips which correspond to the numbering in the main power panel. Lamp enclosure shall be fitted
with a waterproof wiring connector to allow the enclosure to be disconnected and removed from the channel.
Lamp connection shall be above the waterline or shall be waterproof. Safety interlock switch shall turn
off power to the lamps when module enclosure covers are opened. A Class B, ground fault circuit interrupter
shall be provided for each enclosure to turn off power if water enters the enclosure. Lamps shall be
arranged so that they can be replaced without disassembling or removing lamp module.
d. System shall allow for complete system shutdown or by-pass. System shall allow continuous disinfection
while replacing lamps, sleeves, and ballasts; and while cleaning the lamp sleeves.
e. Individual lamp modules weighing 25 kg 55 pounds or less shall be removable without requiring mechanical
lifting devices. Systems with individual lamp modules weighing over 25 kg 55 pounds shall be provided
with a mechanical lifting device as [specified] [shown].
2.2.2.2 UV Lamps
a. Lamp shall be low-pressure mercury vapor type of the hot-cathode, instant-start design in which the
coiled filamentary cathodes are heated by the arc current. The filament shall be a clamped design, and
shall withstand shock and vibration.
b. Lamp shall have the following characteristics:
(1) 90 percent of UV radiation shall be within the wavelengths of 233.7 to 273.7 nm.
(2) Produce a minimum UV intensity of 190 microwatts per square cm at a distance of 1 meter.
(3) Maximum power input of 65 watts (not including ballast losses).
(4) Have a minimum arc length of 1475 mm 58 inches.
(5) Rated to produce zero levels of ozone.
(6) Have a minimum UV output of 26.7 watts at 100 hours.
c. Lamp base shall be metal and ceramic, resistant to UV light and ozone. Lamp tube shall be capable
of transmitting 90 percent of the radiation produced therein.
d. Changing lamps shall not require removal of the sleeve from the lamp module frame. Lamp ballast
shall be capable of being replaced by plant operating personnel.
e. System shall use lamps available from at least 2 currently active lamp manufacturers without modifications
to the system.
2.2.2.3 UV Lamp Sleeve
a. Sleeve shall be clear fused quartz circular tubing. Sleeve shall be rated for transmittance of 89
percent or more and sleeve shall not be subject to solarization over its life. The nominal wall thickness
shall be between 0.8 and 2.09 mm 20 and 53 inch.
b. One end of each sleeve shall be closed and the other end sealed by a lamp end seal and compressed
O-ring. The closed end of the sleeve shall be held in place by means of a retaining O-ring. The sleeve
shall not come in contact with any steel in the frame.
2.2.2.4 Lamp End Seal and Lamp Holder
a. The open end of the lamp sleeve shall be sealed by means of a stainless steel nut which compresses
an external sleeve O-ring seal. The sleeve nut shall have a surface which allows a positive hand grip
for tightening and shall not require any tools for removal.
b. The lamp holder shall be held in place in such a way as to isolate and seal the lamp from the module
frame and other lamps in the module. Should a lamp sleeve fracture, the seal shall prevent moisture
from entering the module frame and the electrical connections to other lamps in the module. The lamp
holder shall incorporate UV resistant materials which prevent lamp sleeve from touching steel.
2.2.2.5 UV Lamp Module Support Rack
Rack shall be stainless steel construction and shall not allow UV light to radiate above the channel when the
lamp modules are energized and fully immersed in the effluent.
2.2.3 Lamp Array Configuration
a. Horizontal lamp configuration shall be a uniform array with lamps parallel to each other and to the
flow. Lamps shall be evenly spaced in horizontal and vertical rows with centerline spacings equal in
both directions. The single array pattern shall be continuous and symmetrical throughout each reactor.
b. Vertical lamp configuration shall be a staggered uniform array with lamps parallel to each other,
but perpendicular to the flow. Lamps shall be evenly spaced with alternating rows offset by one-half
the uniform centerline spacing.
2.2.4 Water Level Control
NOTE: If more than 1 channel is required, there needs to be a positive method
of flow distribution to each channel. The downstream level control device is
designed to build-up negligible head at peak flow rates and may not distribute
flow equally to all channels. The equipment manufacturer should be consulted
for recommended methods of flow distribution in multiple channels.
Automatic Slide/Sluice Gates: These gates are required, two per channel, if
the UV system is to operate in an automatic mode for multiple channel configurations.
These gates are not necessarily supplied by the UV equipment manufacturer.
Additionally, it is the gate manufacturer's responsibility to properly install
and set up each gate, such that a gate closed limit switch, one per gate, is
transmitted to the UV Control Center. Each gate must be able to receive one
opening and one closing signal from dry 10 amp contacts located in the Control
Center. To insure disinfection under all conditions, gate interlocking, both
mechanical and electrical, is required to prevent all gates from being closed
at any given time. These interlocks are the responsibility of the gate manufacturer.
During automatic operation, if channels are to be placed in and out of service,
accommodations should be made to drain the channel when the channel is not in
service. Channels, when out of service, must be completely isolated and not
allow any leakage through slide gates or valves to enter final effluent.
a. A level control device shall be placed [at the discharge end] [both ends] of each channel. Level
control device shall maintain constant channel water level within tolerances required to keep lamps submerged
and shall prevent excessive water layer over the top lamps.
b. [Automatic level controller shall be pivoted above the effluent water surface so that each unit shall
open across the width of the channel. Counterweights shall be adjusted using counterbalance weight at
startup for the full flow range and shall not require adjustment after initial setting. Material of
construction shall be stainless steel, Lexan, Delrin bearings, counterweights of carbon steel with galvanized
finish and corrosion resistant seal of neoprene or other suitable elastomer.] [Fixed weir shall be stainless
steel.] [_____].
c. A water level sensor shall be situated within the channel to provide an alarm indication and/or automatic
system shutdown should the water level drop below the uppermost part of the top row of horizontal lamps.
Alarm contacts for remote annunciation shall also be provided.
2.3 ELECTRICAL
2.3.1 Parameters
a. The system shall be divided into the proper number of parallel electrical subsystems for the peak
design flow.
b. Each electrical subsystem shall be powered from a distribution center and shall include ground fault
circuit detection, circuit protection, modules, and interconnecting cables.
c. One power panel shall be supplied for each module and shall be prewired by the manufacturer, except
for the final connection of the individual modules to the power panel.
d. Ground fault detection shall be standard with the UV equipment manufacturer.
e. Control and monitoring components and power supply shall be housed in NEMA enclosures. Internal
components shall be sealed from the environment. System electronics to be used in an interior environment
shall be housed in enclosures conforming to NEMA 250 Type 12. System electronics to be used in an exterior
and corrosive environment, as defined in NEMA 250, shall be housed in enclosures conforming to NEMA 250
,Type 4X.
f. Sufficient cooling shall be provided to ballasts. Magnetic ballasts shall have a minimum allowable
air flow per ballast of 0.014 cu. m/s 30 cfm.
g. Wiring and electrical connections shall be protected against moisture to prevent electrical shorts
or failure. Electrical installation and materials shall conform to NFPA 70. The unit shall be completely
wired requiring only an external connection for a single external power supply and remote control.
h. Controls and designations shall conform to NEMA ICS 1.
2.3.2 Interconnect Cables
a. Multiconductor unshielded cable shall be suitable for outdoor installation.
b. Insulation shall be thermoplastic rubber with operating range of minus 60 to 125 degrees C minus
76 to 52 degrees F with low temperature flexibility and flame retardants.
c. The UV stabilized jacketing shall be resistant to oils, chemicals, fuels, solvents, and to mechanical
abuse and abrasion.
d. Cable shall be supplied by the equipment manufacturer and shall be of sufficient length and number
for a complete system.
e. Cable shall be of a modular repairable type and shall allow for field replacement and repair of its
components by plant operators.
2.3.3 Connectors and Receptors
Connector shall be waterproof Type S.O. cable for in-line connection. The design shall allow fast and easy positive
coupling and uncoupling. Connector shall be mounted out of possible flood-prone environments. Connector shall
be of a "snap-on" design having no threads and shall allow for visual confirmation that the connection is locked
in place.
2.3.4 Ballasts
Ballast shall conform to NEMA C82.4; shall be coordinated to the ballast supplies; shall be rated for [120] [208]
[240] [277] [480] [volts] [the voltage indicated]; and shall have a power factor of not less than 90 percent
at a crest factor of 2.0 or less, and a voltage range of not less than plus or minus 10 percent. Ballast shall
be suitable for operating at [minus 15] [minus 30] [minus 40] degrees C [5] [minus 22] [minus 40] degrees F and
above. Magnetic ballast shall be located and/or enclosed in an environment not susceptible to the effects of
heat, cold and moisture. Ballast shall be of a modular design allowing for quick disconnect and replacement
by operators.
2.3.5 Cableway
If required by the equipment manufacturer, cable shall be installed in weatherproof and submersible cableway.
The cableway shall be stainless steel, 1.98 or 1.59 mm thick 14 or 16 gauge. Cableway shall be gasketed and
completely watertight under a submerged condition.
2.3.6 Instrumentation and System Controls
2.3.6.1 Controls
Equipment shall be of the fully automatic program control type and shall be capable of receiving standard 4-20
mA control signals from the plant effluent flowmeter. Control of 2 or more banks of modules shall be accomplished
by turning lamp banks on and off in proportion to flow variations. Controls shall continuously adjust the UV
intensity automatically in proportion to wastewater flow. Controls shall require no manual attention other than
adjustment of the required UV intensity.
2.3.6.2 Lamp Status Indicators
a. Indicators shall indicate the status whether ON/OFF of each lamp in the module being powered.
b. Indicators shall indicate the status "POWER ON", only, in each module.
c. The lamp monitoring system shall indicate the geometric location of each individual lamp and operating
status of each lamp by means of a neon lamp or alpha-numeric data display (LED or LCD). Upon lamp failure,
the corresponding lamp shall be illuminated and contact closure shall occur for remote alarm annunciation.
Contact closure for remote annunciation shall be provided to indicate lamp module failure due to ground
fault interruption.
2.3.6.3 UV Intensity Detection System
a. A submersible UV sensor shall continuously sense the UV intensity produced in each bank of lamp modules.
The sensor shall measure only the germicidal portion of the light emitted by the lamps within the channel
between 254.5 and 255.0 nm. The UV intensity shall be displayed on the intensity meter. Each UV intensity
probe shall be located at a point of minimum expected intensity within the lamp array. The probe shall
mount to any lamp in the array and shall be clip-on and self-aligning to assure the proper spacing from
the tube without necessity of handtools. The probe shall be factory calibrated with verification in
the field prior to startup. The UV equipment manufacturer shall provide justification for the sensor
location.
b. One UV intensity meter shall be provided per bank of lamp modules. The meter shall indicate safe
intensity, low intensity, and unsafe intensity by means of color codes on the meter face, or have a 0
to 100 percent scale. The UV intensity meter shall be clearly labeled and located on the remote control
panel.
c. A nonresettable elapsed time meter shall be provided per bank of lamp modules. The meter shall record
hours of UV bank operation from 0 to 99,999 hours.
d. One hand/off/auto switch shall be provided for each UV bank and for each automatic slide gate shown
and specified.
e. Alarms shall be time delayed to prevent nuisance alarms.
2.3.6.4 Minor Alarms
Minor alarms and dry contacts shall be provided to indicate that maintenance attention is required. Minor alarms
shall include:
a. Low warning UV intensity.
b. Individual lamp failure.
2.3.6.5 Major Alarms
Major alarms and dry contacts shall be provided to indicate an extreme condition in which the disinfection performance
may be jeopardized. Major alarms shall include:
a. Low UV intensity.
b. Lamp failure of 2 or more adjacent lamps.
c. Multiple lamp failure.
d. Module failure.
2.3.6.6 Flow Pacing
NOTE: If the system consists of 2 or more banks of lamps, the system can be
flow-paced using a signal from an effluent flow monitoring device in the plant.
a. A flow pacing system shall be provided to turn the UV banks on and off in relationship to the signal
received from the plant effluent flowmeter. Flow pacing sequence shall be as recommended by the UV equipment
manufacturer. Where lamp dimming is used, a controller shall be provided to allow plant operator to
ratio the flow to UV dosage and UV intensity. Where on/off control is used, the system shall allow the
operator to vary the flowrate setting and allow the operator the option to operate individual banks in
either the manual or automatic mode. Logic and time delays shall be provided to regulate the UV bank
ON/OFF cycle to prevent excessive cycling on both startup and shutdown of the UV bank. Multicycle lamps
may be specified in applications which demand up to 100,000 annual cycles.
b. Normal mode of operation shall place each effluent channel continuously in service.
2.4 CLEANING SYSTEM
2.4.1 General Requirements
Provide cleaning equipment and cleaning solutions. Cleaning system shall [be a permanent in-channel installation]
[an out-of-channel installation] [a portable cleaning installation with basin] for cleaning individual lamp sleeves
or entire lamp modules.
2.4.2 Cleaning Tank
Portable cleaning tank shall be stainless steel and equipped with air blower (compressor), lamp module rack,
hose connections and drains. Tank shall hold at least [3 horizontal modules] [1 vertical module] and be equipped
with hard rubber casters. Tank shall have a sealed cover to prevent spilling. Unit shall be equipped with disconnect
switch, a grounded plug and 3 m 10 feet of outdoor cable.
2.4.3 Cleaning Rack
A cleaning rack mounted above the portable cleaning tank shall be provided to hold one horizontal module above
the cleaning liquid for hand wiping of the sleeves.
2.4.4 Cleaning Fluid
Sleeve conditioner and cleaning solution shall be provided for 12 months of normal operation. Conditioner and
cleaning solution shall be supplied in containers not greater than 20 L 5 gallon capacity.
2.5 PAINTING
Shop painting of ferrous metal surfaces shall be in accordance with manufacturer's standard practices.
2.6 ANCHOR BOLTS
Stainless steel anchor bolts of the size required and with ample strength for the purpose intended shall be provided
by the Contractor. Hooked anchor bolts shall be directly embedded during placement of concrete.
PART 3 EXECUTION
3.1 EXAMINATION
After becoming familiar with all details of the work, verify dimensions in the field, and advise the Contracting
Officer of any discrepancy before performing the work.
3.2 INSTALLATION
Perform installation in accordance with the drawings, shop drawings, and manufacturer's instructions and recommendations.
3.3 FRAMED INSTRUCTIONS
Framed instructions under glass or in laminated plastic, including wiring and control diagrams showing the complete
layout of the entire system, shall be posted where directed. Condensed operating instructions explaining preventive
maintenance procedures, methods of checking the system for normal safe operation, and procedures for safely starting
and stopping the system shall be prepared in typed form and posted beside the diagrams. The framed instructions
shall be posted before acceptance testing of the systems.
3.4 FIELD QUALITY CONTROL
3.4.1 Operating Test
After Contractor and Contracting Officer have mutually agreed that the equipment installation is complete and
ready for continuous operation, Contractor shall conduct an operating test of the equipment and controls in the
presence of the Contracting Officer to demonstrate satisfactory operation.
3.4.2 Performance Testing
a. Begin performance testing after the UV equipment has been installed and field tested. Collect samples
at times when the flow through the plant is at or near the peak flow rating from one section of the channel.
Where multiple systems are supplied, the plant flow shall be at or near the peak flow rating of at least
one system or one section of the UV system.
b. The samples collected shall be analyzed for the following, using standard testing methods or procedures:
(1) [Fecal coliform] [_____] in MPN/100 mL just prior to UV disinfection.
(2) [Fecal coliform] [_____] in MPN/100 mL just after UV disinfection.
(3) Total suspended solids prior to disinfection.
(4) Percent UV transmittance at 254 nm with 1 cm cell length prior to disinfection.
c. Performance testing shall continue for 14 days and samples shall be collected 3 times per 24 hour
period. The data obtained shall be recorded in booklet form. Test reports shall indicate the final
position of controls.
d. The effluent quality exiting the UV unit shall be equal to or better than the specification requirement.
Retesting shall continue for at least 2 consecutive days or until satisfactory bacteriological results
have been obtained.
e. Submit statements signed by responsible official or representatives of the manufacturer attesting
to conformance to the specified requirements. The statements shall be dated after performance testing
has been completed, shall name the project, and shall list the specific requirements which are being
certified.
3.5 MANUFACTURERS' FIELD SERVICES
3.5.1 Manufacturer's Representative
Services of a qualified manufacturer's field service representative shall be provided. The representative shall
supervise the installation, adjustment, testing of equipment and instruct plant operators in the care, operation,
and maintenance of the equipment.
3.5.2 Site Visits
Manufacturer's representative shall assist in the proper installation and checking of the equipment for a period
of time necessary to insure a completed installation. The representative shall, for a period not less than three
full days, start up the equipment, supervise initial operations, perform the required field tests and instruct
plant operators in the proper care, operation and maintenance of the equipment. Upon request of the Government,
at any time during the 1-year warranty period, the representative shall recheck the system, recalibrate and adjust
equipment, answer plant operator's questions and review operation and maintenance procedures.
3.6 ADJUSTING AND CLEANING
Equipment shall be tested, calibrated, adjusted and operated to verify its satisfactory operation. Equipment
shall be cleaned of dirt, dust and foreign matter.
3.7 Field Training
Instruction shall be a combination of classroom and hands-on training at the site. Representative shall instruct
designated maintenance and operations personnel in the recommended corrective and preventive maintenance procedures
for the equipment. Field training shall cover each item contained in the operating and maintenance manuals.
3.7.1 Instruction Plan
A lesson plan shall be prepared which shall include the elements presented in the outline specified below. Specific
components and procedures shall be identified in the proposed lesson plan. Specific instruction topics shall
be detailed. Training aids to be utilized in the instruction shall be referenced and attached where applicable
to the proposed lesson plan. Hands-on demonstrations planned for the instruction and estimated duration of each
segment of the training shall be described in the lesson plan.
3.7.2 Training Outline
The elements presented in the following outline shall be included in the instruction as a minimum:
a. Equipment operation.
b. Detailed component description.
c. Equipment preventative maintenance.
d. Equipment troubleshooting.
e. Equipment corrective maintenance.
f. Hands-on demonstrations.