BREATHING

The high pressure breathing air system shall be mounted on a highway ready, dual axle trailer with a 10,000 lbs. Gross Vehicle Weight (GVW) axle classification. The actual dry weight shall not exceed 7500 Lbs. The air system shall include the high pressure air compressor, electric motor, diesel engine driven GenSet, air purification system and air storage system with all of the necessary operating controls as specified below. All operating equipment, components and control devices shall be enclosed within a weather tight metal enclosure. The enclosure shall have swing out doors on each side of the enclosure for access to the compressor and drive assembly and operating control panel. A swing-up rear door shall provide access to all operating controls. The trailer mounted air unit shall be completely factory assembled and tested as a system.

The external construction of the trailer mounted breathing air system enclosure shall be appliance-like; using formed aluminum structures and panels without visible welds, burrs and grinding marks. All structure fasteners shall be concealed and all access panels shall include concealed hinges and push button latches. The interior of the enclosure and the operating control panel shall be illuminated.

All operating control components and performance indicators shall be mounted on a large, illuminated panel. The control panel components and indicators shall be arranged by function for clarity and all indicators located to permit "at sight" operator monitoring. All high pressure air plumbing and fill components shall be rated for 6000 PSI working pressure. All high pressure air plumbing connections shall use compression fit design fittings.

II. Compressor

The ambient air intake and compression shall be accomplished by a four-stage, air-cooled reciprocating compressor with a capacity of 14 CFM charging rate and a working pressure of 6000 PSI.

The design shall include a heavy duty crankcase supporting an iron crankshaft with ball bearings on both ends. The lubrication shall be accomplished by controlled splash of oil and pressure induced migration from the sump of the totally sealed crankcase.

The crankcase shall be piped back to the inlet cylinder to maintain proper crankcase pressure and eliminate the emission oil contaminated air to the atmosphere. The cylinder arrangement shall be a balanced "V" configuration with double-acting, ringed pistons providing minimum vibration and assuring air delivery efficiency throughout the compressor pressure range while operating at a maximum speed of 1750 RPM. Each stage of compression shall be protected by a safety relief valve.

The compressor cylinders must include cooling fins to dissipate heat into the cooling air flow generated by the flywheel fan. Individually mounted coolers shall be located after each stage to cool the compressed air. Accumulated condensation from cooling the compressed air shall be collected in moisture separators on the compressor and piped out through an automatic, timed drain system to a reservoir for periodic collection and proper disposal. Prior to shutdowns, the control system shall allow the compressor to run unloaded (with open drains) for a timed period (purge cycle) in order to purge all cylinders, separators and the crankcase of damaging condensation that develops as compressors cool down.

III. Gasoline Engine

The compressor shall be V-belt driven by an air-cooled, 20 HP gasoline engine. The naturally aspirated engine shall be wired for electric start. The compressor and engine shall be mounted on a common baseplate designed to facilitate belt adjustment. The baseplate shall be supported on the enclosure by zinc plated, steel encased, 400# neoprene isolators to absorb vibration.

IV. Gasoline Engine Driven Control System

The compressor electrical control shall be accomplished via a 12vdc electric system powered by a rechargeable, no-maintenance battery.

As a minimum, the control system shall include the following:

• Air pressure switch to automatically shutdown the compressor when the upper pressure set limit has been satisfied.
• High compressed air temperature shutdown switch. The switch shall include a gauge and a sensor located in a thermowell after the compressor’s fourth stage to measure temperature directly from the air stream. Cylinder surface sensors are not acceptable.
• Compressor low oil level shutdown switch.
• Engine low oil level shutdown switch.
• Electric engine start system.
• Low air storage pressure "restart engine" warning light.
• AirMonitor including CO and H2O electronic detectors with pre-set warning and shutdown limits.

V. Gasoline Engine Driven Control Instrumentation

The operating control system shall include all monitoring devices necessary to indicate normal system operation, fault conditions and shutdowns. These shall be mounted on a control panel at the rear operations center of the unit and arranged so as to permit "at sight" performance monitoring.

As a minimum, the instrumentation required is as follows:

• Keyed engine on/off switch.
• Power “ON” light.
• Compressor interstage and final stage pressure gauges.
• Compressor final stage temperature gauge.
• Compressor normal high air pressure shutdown indicator light.
• High compressed air temperature shutdown indicator light.
• Compressor general fault shutdown indicator light.
• Compressor low oil shutdown light.
• Purge cycle indicator light.
• Hourmeter.
• Enclosure doors warning light.
• Instrument panel light switch
• Emergency stop button.
• Engine low oil shutdown indicator light.
• Inlet filter restriction indicator (located on compressor ambient air intake).
• Digital AirMonitor ( CO and H2O) panel with actual content display in PPM and prompter software keypad for CO monitor calibration. A flow panel with factory plumbed calibration gases shall be included.

VI. Air Purification System

The high pressure air purification system shall be a multi-chamber arrangement that utilizes disposable cartridges manufactured to provide breathing air that meets or exceeds NFPA and CGA Grade "E" specifications and all other equivalent and recognized standards in use worldwide. All system components shall be rated for 6000 PSI working pressure. All chambers in the system shall be constructed of 304 stainless steel to enhance safety and corrosion resistance.

The purification system shall be sized to process 85,000 cubic feet of air at 80° F. and compressed to 6000 PSI between cartridge changes. (A)
The purification system shall be sized to process 165,000 cubic feet of air at 80° F. and compressed to 6000 PSI between cartridge changes. (B)

The system shall include the following:

• Final separator chamber connected to the automatic condensate drain system.
• Check valve to prevent back pressure to the compressor.
• One (1) 33” desiccant cartridge chamber. (A)
•       One (1) 33” purifier cartridge chamber. (A)
• Two (2) 33” desiccant cartridge chamber. (B)
        One (1) 33” purifier cartridge chamber. (B)
• Pressure maintaining valve to assure that the system is maintained pressurized in order to attain the rated processing capacity of the air purification cartridge(s).
• Safety relief valve.
• Drain valve to relieve the system pressure for maintenance.
• Stem-mounted gauge for system pressure verification.
• The system shall be designed so that filling cannot occur in the event that any of the disposable cartridge is not installed.

VII. High Pressure Breathing Air Storage System

The high pressure air storage system shall meet or exceed all current DOT code requirements and include the number of cylinders specified below. The air storage system shall include the interconnecting piping arrangement selected and be completely factory assembled and tested at maximum working pressure.

The air storage system shall consist of:

Two (2) DOT 6000 PSI cylinders each with a capacity of 509 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for bulk filling.
Two (2) DOT 6000 PSI cylinders each with a capacity of 509 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for cascade filling.
Three (3) DOT 6000 PSI cylinders each with a capacity of 509 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for bulk filling.
Three (3) DOT 6000 PSI cylinders each with a capacity of 509 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for cascade filling.
Four (4) DOT 6000 PSI cylinders each with a capacity of 509 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for bulk filling.
Four (4) DOT 6000 PSI cylinders each with a capacity of 509 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for cascade filling.
Two (2) ASME 6000 PSI cylinders each with a capacity of 525 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for bulk filling.
Two (2) ASME 6000 PSI cylinders each with a capacity of 525 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for cascade filling.
Three (3) ASME 6000 PSI cylinders each with a capacity of 525 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for bulk filling.
Three (3) ASME 6000 PSI cylinders each with a capacity of 525 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for cascade filling.
Four (4) ASME 6000 PSI cylinders each with a capacity of 525 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for bulk filling.
Four (4) ASME 6000 PSI cylinders each with a capacity of 525 cubic feet of air at 6000 PSI. The piping of air storage shall be arranged for cascade filling.

VIII. SCBA/SCUBA Cylinder Containment Fill Station

The mobile fill station shall have the capacity for filling two (2) SCBA/SCUBA cylinders simultaneously or separately. The enclosure shall be designed to contain the impact of suddenly expanded high pressure air and all displaced fragments in the unlikely event of a cylinder or fill component rupture. The containment design shall feature a loading door that is trapped inside the fill enclosure cabinet frame when closed. The enclosure shall include an automatic, safety interlock to prevent filling unless the loading door is completely in the closed position and a safety relief valve to protect operators in the event that the SCBA/SCUBA fill pressure exceeds 4750 PSIG.

The external construction of the high pressure, breathing air fill station shall be appliance-like; using formed, fabricated steel structures and panels without visible welds, burrs or grinding marks.

IX. SCBA Fill Enclosure and Access Door Control

The fill station must allow the complete fill process to be accomplished from the front and include an access door control that enhances the enclosure containment design, is simple to operate and requires minimal physical operator effort. Two (2) fill whips, each fitted with a cylinder fill adapter, shut-off valve and pressure bleed valve shall be located within the enclosure.

The access door assembly shall include two (2) integral, steel cylinder sleeves to secure the SCBA/SCUBA cylinders while being filled. The assembly shall tilt forward until horizontal, positioning the cylinder sleeves at the optimal height for loading and unloading cylinders with minimal operator effort.

The access door control shall include an air actuator handle designed to operate a pneumatic cylinder to open and close the access door. For opening, the handle shall lower the access door, releasing it from behind the cabinet frame and allowing the operator to pull the door forward to load and unload SCBA/SCUBA cylinders. For closing, the access door is rotated up to the vertical position and the handle shall then raise and trap it behind the cabinet frame. When fully raised, the door trips the safety interlock allowing air to flow to the fill station.

The access door shall be supported on the enclosure frame with an adjustable bearing bushing on each side assuring a balanced, smooth rotation and effortless operation when opening and closing. A gas strut shall secure the assembly to the enclosure so that it does not require operator support when opening or closing and to cushion the access door landing when opened.

X. SCBA/SCUBA Cylinder Fill Controls

The SCBA/SCUBA cylinder fill control system shall include a regulated air control panel with all components, devices and piping arrangement necessary to direct supplied compressed high pressure breathing air to the SCBA/SCUBA cylinders being filled.

A cascade control system shall be included for the number of banks specified below. The cascade control system shall permit filling or drawing down each air storage cylinder, independently of each other, while filling SCBA/SCUBA cylinders. An air storage by-pass valve shall be included to permit filling SCBA/SCUBA cylinders from the compressor. (C)

The control system shall include a dual regulator package for safely filling SCBA/SCUBA cylinders with two (2) different pre-set pressures. The package shall include installation of the standard and an additional regulator behind the panel at pre-set pressures. A selector button located at the control panel shall be required to select air flow from the regulator with the highest pre-set pressure. A pneumatic actuator valve shall return the air flow to the low pressure regulator after every high pressure fill cycle. (D)

An additional "dedicated fill circuit" shall be included to safely fill SCBA/SCUBA cylinders at a different pressure than that flowing from the main control panel regulator(s). The "dedicated fill circuit" shall include an adjustable, pre-set regulator installed behind the control panel plumbed directly to a dedicated fill whip and adapter located in the fill enclosure and a separate panel mounted flow valve and gauge. (E)

The fill control system shall include an integral retractable air reel with 50’ of hose and CGA fitting for filling remote air storage systems. (F)

The fill control system shall include an integral retractable air reel with 100’ of hose and CGA fitting for filling remote air storage systems. (G)

All air flow components and indicators must be labeled and mounted on a steel control panel on the front of the unit and located above the fill enclosure. The panel shall be painted in a matte shade with a textured finish to eliminate glare and enhance the visibility of gauges and indicators. The panel shall be illuminated.The panel shall be designed so that it can slide forward, out of the compartment, and tipped down so that all piping and components are accessible for maintenance.

As a minimum, the air control panel must include the following:

• Inlet pressure gauge.
• Adjustable, 0-6000 PSI self-relieving regulator.
• Regulator outlet pressure gauge.
• Air storage by-pass valve
• SCBA/SCUBA cylinder(s) fill control valve.
• SCBA/SCUBA cylinder(s) fill pressure gauge.
• Panel lights on/off switch.
• Two (2) bank cascade control with “To” and “FROM” valves and gauge per bank. (C)
• Three (3) bank cascade control with “To” and “FROM” valves and gauge per bank. (C)
• Four (4) bank cascade control with “To” and “FROM” valves and gauge per bank. (C)
• Dual regulator high pressure selector button. (D)
• “Dedicated fill circuit” flow valve and gauge. (E)
• Air reel fill valve and gauge . (F,G)

XI. Trailer and Enclosure

The trailer shall be a dual axle design with a 10,000 Lbs. GVW highway classification. The trailer shall comply with all federal and state highway safety regulations and include electric brakes, running, rear and brake lights, safety chains, spare tire and a ball type hitch. A 20 gallon fuel tank and a compressor condensate reservoir shall also be included. Three (3) jack stands shall be provided for stability when stopped for filling operations.

The enclosure housing for all the high pressure air system components shall be a formed aluminum, weather protected assembly and include main access and utility, swing out doors on each side and one (1) swing-up operator control access door at the rear. All metal surfaces on the trailer mounted high pressure air system shall be protected with a scratch-resistant, powder coat red finish.