GENERAL                                                                      Date 10/20/03






Work Included:

The work specified in this section includes furnishing, installing, and testing a hose type of vehicle interior cleaning system at the location shown on the drawings. It shall be a single service lane vacuum system with a festooned hose at the front and/or rear doors for cleaning the interior of fixed route transit, paratransit, and tour buses. The cyclone collector, vacuum blower and festooned hose may be located either at the service lane as a package or separately at a remote location.  The hose festoon system shall have a chord supported from the roof or a built-in arm 20’ high.  The festoon shall be connected to an automatic retraction mechanism (not counterweighted) thru a series of pulleys. Include all of the equipment as specified herein to interconnect the various system components.  Not included is the work of bringing the utilities to the vacuum equipment.






Codes and Regulations:

The bus vacuum system shall be in accordance with national and commercial standards, codes, rules, and regulations, local ordinances, and other authorities having jurisdiction of this work. Electrical work shall be in accordance with the applicable provisions of the National Electric Code for Class 1 Division 2. Emissions shall conform to AQMD regulations and noise, to OSHA regulations




If the vacuum system supplier is a subcontractor for a new facility, he shall coordinate the location of the vacuum cleaning equipment with the location of other mechanical and electrical installation work.  Coordinate the positioning of the electrical stub-ups, if any, and the location of the cyclone/blower assembly.  If the vacuum system supplier is working in an existing facility as a prime contractor, he must do the same with the owner.  




All metal parts not galvanized shall be cleaned and covered with two coats of primer and two finish coats of semi-gloss industrial enamel paint. The finish color is to be selected by the district or project engineers







Submit front, end, and plan view drawings of the collector and festooned hoses.  Also include drawings of the piping/control schematic, bill of material, and recommended spare parts. Engineer's review and approval of the drawings is required before proceeding with fabrication.



Installation and Erection Instructions:

Submit complete installation instructions including technical literature on the vacuum blower, electric controls, festooned hose, dumpster or 55 gal drum, and silencer for review by the engineer.









Test Data:

Submit for approval all test results per par. 3.2




Submit a letter that all equipment is in operating condition per par. 3.2.A



Operation and Maintenance Manual:

6 copies and include maintenance instructions, drawings, necessary spare parts, and product data sheets.












All major equipment shall be shipped upright and ready for unloading and installation. Festoon tube, spare parts, and miscellaneous hardware shall be shipped crated, labeled, and packaged for safe handling to avoid damage. 






The general contractor or owner shall be responsible for unloading and storing festoon tube, spare parts, and miscellaneous hardware in a dry safe area prior to installation. 















Description of System:

The 3” single lane festooned hose bus vacuum assembly shall be Robertson Air Systems or equal.  The equipment shall conform to all the features shown on the drawings and as described in these specifications.  It shall consist of one service lane with a festooned hose for the front door and/or for the rear door. At the pick-up end of the hose shall be a lance with two or three explosion proof push button switches in the handle; one to turn on the vacuum blower, one to extend the festooned hose, and the other to retract the festooned hose.  Hard wire shall connect these switches to their respective automatic devices. The festoon shall consist of a chord one end of which is fastened to an intermediate point in the hose and the other end routed to the retraction device thru pulleys supported from above in the roof or from by an arm in the support structure. Similarly, a chord and pulleys shall be provided to manually raise the lance to the roof when not being used.  The collected trash shall be deposited into a 55 gallon drum or dumpster located beneath the collector.  A silencer on the blower discharge shall limit the noise from the vacuum blower to the specified levels.          





Sequence of Operation:

Litter too large to be vacuumed shall be picked-up manually and deposited into a trash container located nearby. Next, the operator shall enter the front or rear door with the 3” lance while extending the hose with the push button in the handle of the lance.  This push button will automatically start the vacuum blower.  The operator shall vacuum around the driver’s area, the front door step well, and throughout the length of the entire bus including the rear door step well.  When finished the operator shall retract the hose with the second push button in the handle of the lance. When vacuuming for all the buses is finished at the end of the shift, the operator may hoist the lance to the roof with the manual festoon.  The operators shall be responsible for replacing the full drum or dumpster with the spare before the trash causes a plug in the cyclone.  The blower shall stop by a timer.      






The pick-up velocity through the 3” lance opening shall be no less than 13,000 fpm and shall be verified by test per Par. 3.2.2 (b).  Festooned support and control of the hose is the only acceptable method; hose reels are unacceptable.  The noise level from the lance shall not exceed 90 dba at the operators ear.  The noise level from the vacuum blower at floor level shall not exceed 85 dba.






Electric power: 208/230/460 volt, 3 phase, 60 hz, with sufficient capacity for the vacuum blower. Compressed air for the brake on the festoon chord.





Allowable Space:

The footprint of the collector/blower assembly shall be 3’ wide by 4’deep with a 55 gallon drum or 4’deep by 8’ wide for a dumpster both exclusive of the festoon.   The height of the cyclone/blower assembly shall not exceed 17’.  The preferable height for the festoon is 20’ or higher, but lower heights can be accommodated.





Acceptable Suppliers:




Robertson Air Systems




33381 Coral Reach




Dana Point , CA  92629




Tel: 714-420-1450




Fax: 866-906-1450




E-mail: jim@robertsonairsystems.com




Web Site: www.robertsonairsystems.com  






Items necessary for complete and working installation of one collector assembly and one or two 3” festooned hoses servicing one service lane.





One Cyclone Collector Assembly with involute inlet and seismic support structure located either adjacent to the service lane(s) or in a remote location.





One High Pressure Vacuum Blower w/Motor bolted to the top of the cyclone below the roof or above the roof with a spool section extending thru the roof. 





One Silencer on the vacuum blower discharge.





One Transition on the inlet to the cyclone.





One Front and/or Rear Door Hose Festoon located next to the respective bus doors and supported from the roof by a nylon chord connected to the retraction device.





One Flexible Duct located between the bottom of the cyclone and airtight lid.





One Airtight Lid located at the bottom of the cyclone discharge cone and the 55 gallon drum or dumpster. 





One or Two  3" Lance(s) on the end of the vacuum hose including a handle with three push buttons.





One or Two 3 ½”Vacuum Hose(s) by 37’long with smooth inner surface





One 55 Gallon Drum or Dumpster shall interface with the air tight lid located beneath the discharge cone of the cyclone separator. 





One Spool located between the top of the cyclone and the inlet to the vacuum blower only when the vacuum blower is mounted outside above the roof.






One Cyclone Plugged Detection Control located in the cone of the cyclone






One Electric Control Cabinet located on one end of the support structure or in a remote location.





One "On-Off-Auto" Switch located on the front of the electric control cabinet. 





Two 4” Slide Gates located in the vacuum piping connecting the festoon with the cyclone collector for a two lance system only





One or Two 3” Lances located at the pick-up end of the festooned hoses





One Set of Spare Parts as listed on the plans. 





Miscellaneous Hardware Including: red-heads for the cyclone, vacuum piping, adhesive, electric wire, conduit, pneumatic fittings, lubricants, ring clamps, and touch-up paint.










Cyclone/Blower Collector Assembly: 

The cyclone/blower collector assembly shall be by Robertson Air Systems or equal. It shall consist of two major assemblies i.e. the cyclone/blower assembly and support structure.  The cyclone shall be fabricated from 12 gage metal.  It shall be sized for one only 3” lance with a pick-up velocity of 13,000 ft/min.  Collection efficiency shall be 100% for litter and 99.9% for dust down to 30 microns. Flange the cone just below the body portion to provide access to the interior of the cyclone.

  The support structure shall consist of four 1/4”x 3" angle legs; four 1/2" thick x 9"sq. base plates with holes for four 5/8"dia. redheads; framing for mounting the electric control cabinet and/or the pneumatic control cabinet on one end; 1/4" x 3" angle cross bracing on top and 1/4"x 2" diagonal cross bracing as required on the sides.  No horizontal cross bracing shall be any lower than 6 1/2' from the ground in front to allow access to the drum or dumpster.  Legs shall be flanged near the middle to permit shipping in the upright position.    





Airtight Lid:

The airtight lid shall be located below and connected to the cyclone with an airtight flex hose.   It shall interface with the top of the drum or dumpster to form an airtight seal.   





Electric Control Cabinet:

It shall be pre-wired for 240 volts or 480 volts, 3 phase, 60 hz, in an explosion proof enclosure, and shall contain: combination disconnect full voltage magnetic  motor/starter; and overload protection in all three phases. Provide all other necessary programmed controls, relays, timers, and terminal blocks. Fan "Start/Stop" push buttons and pilot light shall be on the control panel door.  Cabinet shall meet or exceed all state and/or local electrical codes.





Vacuum Festooned Hose Assy.:

The hose shall be 3 ½” inside diameter and smooth on the inside and have a negative pressure rating of 7 inches mercury.  A nylon chord shall connect the hose from an intermediate attachment point to the retraction cylinder thru overhead pulleys.  Vacuum piping shall connect the bottom of the cylinder to the vacuum blower with an optional explosion proof booster vacuum blower in between.  Extending and retracting the hose shall be controlled by valves regulating the vacuum pressure in the cylinder.  A second nylon chord, cleat, and pulleys shall be used to manually elevate the lance when not being used.






Shall be 3”dia.x 48"long, contoured on the end, and made of aluminum or plastic with  a 30o elbow, and a 360o swivel with two aluminum handles.  The forward or main handle shall contain the three Piezo explosion proof push button switches.





Vacuum Blower:

Shall be vertical shaft, Class B spark proof construction, flanged mounted to the top of the cyclone with a 208/230/460 volt, 3 phase, 60 hz., explosion proof, motor with aluminum wheel and motor removable from the drive side.  It shall have flanges on the inlet and discharge openings.  It shall have power and capacity to produce a velocity of 13,000 ft./min. minimum thru a 3” lance per the requirements of  test 3.2.C and it shall comply with the noise requirements of  test 3.2.D






Outlet Silencer:

Vibro-Acoustics or equal type RDS flanged mounted to the blower discharge. Construction shall consist of continuously welded hot rolled steel casing; fiberglass acoustical media, galvanized perforated metal, fiberglass cloth erosion protection, and reinforced steel angle flanges. Pressure drop shall not exceed 1".






A doughnut shaped spacer silencer located between the cyclone and vacuum blower with flanged ends to elevate the blower above the roof.  It shall have an inner perforated cylinder and an outer shell with sound absorbing material in between.  Is normally used only when the blower is mounted thru the roof on the outside.





Plug Detect ion Control:

It shall be an acoustic type to shut-off the blower in case of a plug in the cyclone.  It shall consist of an amplifier receiver (microphone) and a transmitter (loudspeaker) with two sensors located 12” above the bottom of the cones on opposite sides of the cyclone.  The sound shall not be audible to the human ear and a timer shall prevent false alarms.  It shall shut off the blower if a plug is detected.   
















At the owner’s or contractor’s request  the supplier shall send a qualified representative to the jobsite, to supervise others responsible for carrying out all the work related to the equipment installation. It shall be the responsibility of the owner or contractor to ensure that the equipment to be furnished and installed fits the available space.





The whole collector/blower assembly shall be shipped upright in two parts.  The lower part of the support structure with four flanged legs on both ends and the upper part with the cyclone, vacuum blower, and four legs with matching flanges on the bottom.  Each part can be lifted from the truck with a fork lift and installed into its proper place in the facility.  The lower part shall be lag bolted to a cement base and the upper part bolted to the flanges on the lower part.  All other accessories including the festoon and utilities should be connected according to the installation instructions.            






At the request of the owner or contractor the supplier shall send a qualified representative to the jobsite to conduct the following tests and submit a report for approval.






From the three push buttons on the lance operate the vacuum blower and festoon through a number of cycles to the satisfaction of the engineer and/or owner.






Measure the current in all three legs of the fan motor with one vacuum hose wide open and then closed off.





Pick-up Velocity (capacity):

Measure the pick-up air velocity in feet per minute with only one lance open.  It should be 13,000 ft/min. minimum.






Vacuum Pressure:

With the booster blower turned off measure the vacuum pressure in the festoon piping with the lance wide open and then also closed off.  It should be about 41” wide open and 38” closed off .






Lift Pressure:

With the booster blower (if used) and the main vacuum blower operating measure the negative vacuum pressure in the festoon piping. 






Noise Level:

Take four DBA noise readings with the vacuum blower and booster blower operating and the vacuum air at the lance shut-off at 5 feet above the floor level at a distance of 5' all around starting in front of the cyclone or blower if it is on the ground.  These should be 85 dba or lower.  The noise of the vacuum air entering the lance is not controllable and the operator should be required to wear ear protection.  







Under normal operating conditions for one or two shifts, there should be no evidence of any litter passing thru the cyclone collector.  If litter passes thru the supplier shall make corrections to remedy this problem.