New York Codes, Rules and Regulations › Title 1 - DEPARTMENT OF AGRICULTURE AND MARKETS › Appendices › Appendix 4

Current through Register Vol. 46, No. 28, July 10, 2024
PASTEURIZATION EQUIPMENT AND CONTROLS-TESTS
(cf. Part 2)
I. Testing Apparatus Specifications
TEST THERMOMETER
Type.
-Mercury-actuated; readily cleanable; plain
				front, enameled back; length 12 inches, immersion point to be etched on stem,
				mercury to stand in contraction chamber at 32°F (0°C).
Scale Range.
-At least 12°F (7°C) below and
				12°F (7°C) above the pasteurization temperature at which the operating
				thermometer is used, with extensions of scale on either side permitted,
				protected against damage at 300°F (149°C).
Temperature Represented by Smallest Scale
				Division.
-0.2°F (0.1°C).
Number of Degrees per Inch of Scale.
-Not more than
				6 Fahrenheit degrees or not more than 4 Celsius degrees.
Accuracy.
-Within 0.2°F (0.1°C) plus or
				minus, throughout specified scale range. The accuracy shall be checked against
				a thermometer which has been tested by the National Bureau of Standards.
Bulb.
-Corning normal or equally suitable
				thermometric glass.
Case.
-Suitable to provide protection during
				transit and periods when not in use.
GENERAL PURPOSE THERMOMETER
Type.
-Pocket type; mercury-actuated.
Magnification of Mercury Column.
-To apparent width
				of not less than 0.0625 of an inch.
Scale Range.
-30°F (-1°C) to 212°F
				(100°C), with extension on either side permitted. Protected against damage
				at 220°F (105°C).
Temperature Represented by Smallest Scale
				Division.
-2°F (1°C).
Number of Degrees per Inch of Scale.
-Not more than
				52 Fahrenheit degrees or not more than 29 Celsius degrees.
Accuracy.
-Within 2°F (1°C) plus or minus,
				throughout the specified scale range. Checked periodically against a known
				accurate thermometer.
Case.
-Metal, provided with a fountain pen
				clip.
Bulb.
-Corning normal or equally suitable
				thermometric glass.
ELECTRICAL CONDUCTIVITY MEASURING DEVICES
Type.
-Wheatstone bridge, Galvanometer,
				Milliammeter; manual or automatic.
Conductivity.
-Capable of detecting change produced
				by the addition of 10 ppm of sodium chloride, in water of 100 ppm of
				hardness.
Electrodes.
-Standard.
Automatic Instruments.
-Electric clock, time
				divisions not less than 0.2 of a second.
STOPWATCH
Type.
-Pocket type, open face, hand indicating
				fractional seconds.
Accuracy.
-Accurate to 0.2 of a second.
Hands.
-Sweep hand, one complete turn every 60
				seconds or less.
Scale.
-Divisions of not over 0.2 of a
				second.
Crown.
-Depression of crown starts, stops, and
				resets to zero.
II. Test Procedures
Equipment and field tests to be performed by the regulatory
				agency are listed and suitably referenced below. The results of tests shall be
				recorded on suitable forms and filed as the regulatory agency shall
				direct.
TEST 1. INDICATING THERMOMETERS-TEMPERATURE
				ACCURACY
Reference.
-Item 16p(D).
Application.
-To all indicating thermometers used
				for measurement of milk temperature during pasteurization, including airspace
				thermometers.
Frequency.
-Upon installation and once each 3
				months thereafter.
Criteria.
-Within 0.5°F (0.25°C) for
				pasteurization thermometers and 1°F (0.5°C) for airspace thermometers
				plus or minus, in a specified scale range.
Apparatus.
-1. Test thermometer meeting
				specifications under Appendix 4, Part I.
2. Water or oil bath and agitator.
3. Suitable means of heating water or oil bath.
Method.
-Both thermometers exposed to a water or
				oil medium of uniform temperature. Indicating thermometer reading is compared
				to the reading of the test thermometer.
Procedure.
-1. Prepare 10 gallons of water in a
				milk can or a quantity of oil in an oil bath by raising the temperature of the
				water or oil to within a range of 3°F (2°C) of the appropriate
				pasteurization temperature or airspace temperature.
2. Remove heat source, agitate water or oil bath
				rapidly.
3. Continue agitation. Insert indicating test thermometer to
				indicated immersion point during the test.
4. Compare both thermometer readings at the temperature reading
				within the test range.
5. Repeat comparison of readings.
6. Record thermometer readings, thermometer identification, or
				location.
Corrective Action.
-Do not run test if mercury
				column has been split or capillary tube is broken as thermometer should be
				returned to the factory for repair. When the indicating thermometer differs
				from the test thermometer by more than 0.5°F (0.25°C) and the airspace
				thermometer by more than 1°F (0.5°C), the scale plate of the indicating
				thermometer should be adjusted to agree with the test thermometer. Retest the
				thermometer after adjustment.
TEST 2. RECORDING THERMOMETERS-TEMPERATURE
				ACCURACY
Reference.
-Item 16p(D).
Application.
-To all recording and
				recorder/controller thermometers used to record milk temperatures during
				pasteurization.
Frequency.
-Upon installation, at least once each
				3 months and whenever recording pen-arm setting requires frequent
				adjustment.
Criteria.
-Within 1°F (0.5°C) plus or
				minus, in specified scale range.
Apparatus.
-Pasteurizer indicating thermometer
				previously tested against a known accurate thermometer, three 10-gallon milk
				cans, or suitable vats or containers, agitator, suitable means of heating water
				baths, and ice.
Method.
-The testing of a recording thermometer for
				temperature accuracy involves the determination of whether or not the
				temperature pen-arm will return to within 1°F (0.5°C) of its previous
				setting after exposure to boiling water and melting ice.
Procedure.
-1. Adjust the recording pen to read
				exactly as the previously tested indicating thermometer in the temperature
				range for the pasteurization process being used after a stabilization period of
				5 minutes at a constant temperature. The water bath shall be rapidly agitated
				throughout the stabilization period.
2. Prepare one water bath by heating to the boiling point.
				Maintain temperature. Prepare a second container with melting ice. Place water
				baths within working distance of the recorder sensing element.
3. Immerse the sensing element of recorder in boiling water for
				not less than 5 minutes.
4. Have a can of water adjusted to a temperature within the
				testing range for the pasteurization process being used.
5. Remove the sensing element from the boiling water and
				immerse in water at a temperature within the testing range for the
				pasteurization process being used. Allow a 5-minute stabilization period for
				both indicating and recording thermometers. Compare readings of 1°F
				(0.5°C) plus or minus, indicator thermometer reading.
6. Remove sensing element from bath at operating temperatures
				and immerse in melting ice for not lean than 5 minutes.
7. Remove sensing element from ice water and immerse in water
				at a temperature within the testing range for the pasteurization process being
				used. Allow a 5-minute stabilization period for both indicating and recording
				thermometers. Compare readings of 1°F (0.5°C) plus or minus, indicator
				thermometer reading.
8. Record results.
Corrective Action.
-If the pen does not return to
				1°F (0.5°C) plus or minus of indicating thermometer reading, the
				recording thermometer should be repaired.
Note.-When this test is performed on recorder/controllers used
				with HHST pasteurization systems, an oil bath shall be substituted for the
				boiling water in step 3. above. The temperature of the oil bath shall be such
				that the temperature sensing element of the recorder/controller system is
				raised to a temperature above that which the recorder/controller is capable of
				sensing.
TEST 3. RECORDING THERMOMETERS-TIME
				ACCURACY
Reference.
-Item 16p(D).
Application.
-To all recording and
				recorder/controller thermometers used to record time of pasteurization.
Frequency.
-Upon installation and at least once
				each 3 months thereafter.
Criteria.
-The recorded time of pasteurization
				shall not exceed the true elapsed time.
Apparatus.
-1. A watch graduated at intervals not
				to exceed 1 minute, and accurate to within 5 minutes in 24 hours.
2. A pair of dividers, or any other suitable device for
				measuring short distances.
Method.
-Comparison of the recorded time over a
				period of not less than 30 minutes with a watch of known accuracy. For
				recorders utilizing electric clocks, check cycle on face plate of clock with
				known cycle; observe that clock is in operating condition.
Procedure.
-1. Determine if chart is appropriate to
				recorder.
2. Inscribe reference mark at the pen point on the recorder
				chart at the start of the holding period and record the time.
3. At the end of 30 minutes by the watch, inscribe a second
				reference mark at the pen point position on the chart.
4. Determine the distance between the two reference marks and
				compare the distance with the time-scale divisions on the record chart at the
				same temperature.
5. For electric clocks, remove face plate, compare cycle
				specification on face plate with the current cycle utilized.
6. Enter finding on chart and initial. Record results.
Corrective Action.
-If recorded time is incorrect,
				the clock should be adjusted or repaired.
TEST 4. RECORDING THERMOMETERS-CHECK AGAINST INDICATING
				THERMOMETER
Reference.
-Item 16p(D).
Application.
-To all recording and
				recorder/controller thermometers used to record milk temperatures during
				pasteurization.
Frequency.
-At least once each 3 months by
				regulatory agency; daily by plant operator.
Criteria.
-Recording thermometer shall not read
				higher than corresponding indicating thermometer.
Apparatus.
-No supplementary materials
				required.
Method.
-This test requires only that the reading
				of the recording thermometer be compared with that of the indicating
				thermometer at a time when both are exposed to milk at a stabilized
				pasteurization temperature.
Procedure.
-1. While milk is at a stabilized
				pasteurization temperature, read indicating thermometer.
2. Immediately inscribe on the recording-thermometer chart a
				line intersecting the recorded temperature arc at the pen location; record on
				the chart the indicating thermometer temperature; initial.
3. Record results.
Corrective Action.
-If recording thermometer reads
				higher than indicating thermometer, the pen should be adjusted by the
				operator.
TEST 5. FLOW-DIVERSION DEVICE-PROPER ASSEMBLY AND
				FUNCTION
Reference.
-Item 16p(D).
Application.
-To all flow-diversion devices used
				with continuous-flow pasteurizers.
Frequency.
-Upon installation and at least once
				each 3 months thereafter.
Criteria.
-The flow-diversion device shall function
				correctly in operating situations and shall de-energize the metering pump in
				the event of malfunction or incorrect assembly.
1. LEAKAGE PAST VALVE SEAT(S)
Apparatus.
-Suitable tools for disassembly of
				flow-diversion device and sanitary piping.
Method.
-Observe the valve seat(s) of the
				flow-diversion device for leakage.
Procedure.
-With the system operating with water,
				place the flow- diversion device in diverted-flow position. Disconnect the
				forward flow piping; observe the valve seat for leakage. Check leak escape
				ports to see if they are open.
Corrective action.
-If leakage is noted, device
				must be dismantled and defective gaskets replaced or other suitable repairs
				made.
2. OPERATION OF VALVE STEM(S)
Apparatus.
-Suitable tools for disassembly of
				flow-diversion device and sanitary piping.
Method.
-Observe flow-diversion device valve
				stem(s) for ease of movement.
Procedures.
-When a stem packing nut is used,
				tighten stem packing nut as much at possible. Operate system; place device in
				forward and diverted flow several times. Note freedom of action of valve
				stem.
Corrective action.
-If valve action is sluggish,
				suitable adjustment or repair shall be made to permit stem to act freely in all
				positions, with packing nut, when used, fully tightened.
3. DEVICE ASSEMBLY, SINGLE STEM DEVICE
Apparatus.
-Sanitary fitting wrench.
Method.
-Observe function of metering pump when
				flow-diversion device is improperly assembled.
Procedures.
-a. With HTST system in operation,
				unscrew by one-half turn, the 13H hex nut which holds the top of the valve to
				the valve body. This should de-energize the metering pump. This test should be
				run with no piping connected to the forward flow port of the device since there
				can be sufficient force from the piping to keep the forward flow port tightly
				clamped even though the hex nut is loosened.
b. With the HTST system in operation and the flow-diversion
				device in the diverted position, remove the connecting key located at the base
				of the valve stem. The metering pump should be de-energized.
Corrective action.
-If metering pump fails to
				respond as indicated, immediate checks of the device assembly and wiring are
				required to locate and correct the cause.
4. DEVICE ASSEMBLY, DUAL STEM DEVICE
Apparatus.
-None.
Method.
-Observe function of metering pump when
				flow-diversion device is improperly assembled.
Procedures.
-a. With the device in diverted-flow
				position, remove one actuator clamp.
b. Move the device to the forward-flow position and disconnect
				stem from actuator.
c. Move the device to the diverted-flow position and turn on
				the metering pump. The metering pump should not run.
d. Reassemble the device by moving it to the forward-flow
				position and reconnecting the stem to the actuator.
e. Move the device to the diverted-flow position and replace
				the actuator clamp.
f. Repeat the procedure for the other actuator.
Corrective action.
-If metering pump fails to
				respond as indicated, an immediate check of the device assembly and wiring are
				required to locate and correct the cause.
5. MANUAL DIVERSION
(when booster pump is
				installed in the HTST system)
Apparatus.
-None.
Method.
-Observe the response of the system to
				manual diversion.
Procedure.
-With the HTST system in operation and
				the flow-diversion device in the forward-flow position, press the manual
				diversion button. This should (a) cause the valve to assume the divert
				position, and (b) de-energize the booster pump; the pressure differential
				between raw and pasteurized milk in the regenerator should be
				maintained.
Corrective Action.
-If (a) and (b) above do not
				occur as described or the necessary pressure differential between raw and
				pasteurized milk is not maintained, the assembly and wiring of the HTST system
				must be immediately reviewed and the indicated deficiencies corrected.
6. RESPONSE TIME
Apparatus.
-Stopwatch. The stopwatch should be used
				to determine that the response time interval does not exceed 1 second.
Method.
-Determine the elapsed time between the
				instant of the activation of the control mechanism at cut-out temperature on
				declining temperature and the instant the flow-diversion device takes the fully
				diverted-flow position.
Procedure.
-a. With water or oil bath at a
				temperature above cut-out temperature, allow the water or oil to cool
				gradually. At the moment the cut-out mechanism is activated, start the watch
				and the moment the flow-diversion device takes the fully-diverted position,
				stop the watch.
b. Record results.
Corrective Action.
-Should response time exceed 1
				second, immediate corrective action must be taken.
7. TIME DELAY INTERLOCK WITH METERING PUMP.
Application.
-To dual stem flow-diversion devices
				with a manual forward-flow switch.
Apparatus.
-None.
Method.
-Determine that the device does not assume
				a manually induced forward-flow position while the metering pump is
				running.
Procedures.
-With the system running in forward
				flow, move the control switch to the "Inspect" position and observe that the
				following events automatically occur in sequence:
a. The device immediately moves to the diverted-flow position
				and the metering pump is turned off.
b. The device remains in the diverted-flow position while the
				metering pump is running down.
c. After the metering pump stops turning, the device assumes
				the forward-flow position.
d. Repeat the above procedure by moving the control switch to
				the cleaned-in-place (CIP) position.
e. Record test results and seal the control enclosure.
Corrective action.
-If the above sequence of
				events does not occur, either a timer adjustment or wiring change is
				required.
TEST 6. LEAK PROTECTOR VALVE
Reference.
-Item 16p(D).
Application.
-To all pasteurizer inlet and outlet
				valves.
Frequency.
-Upon installation and at least once
				each 3 months thereafter.
Criteria.
-No leakage of milk past the valve seat
				in any closed position.
Apparatus.
-No supplementary materials
				required.
Method.
-By observing when the piping is
				disconnected from the valve outlet whether or not leakage past the valve seat
				occurs when milk pressure is exerted against the upstream face of the
				valve.
Procedure.
-1. During normal operation, while milk
				pressure is exerted against the valve inlet, fully close the valve and
				disconnect the outlet piping.
(Caution: Care must be taken to avoid contamination of the
				valves or the piping.)
2. Observe whether or not any milk is leaking past the valve
				seat into the valve outlet.
3. In the case of plug-type valves, turn the valve to the
				just-closed position, and examine for leakage into the valve outlet.
4. Reconnect the outlet piping.
5. Record identity of the valve, and findings, for office
				record.
Corrective Action.
-If leakage past the valve seat
				should occur in any closed position, the valve plug should be reground, gaskets
				replaced, springs replaced or other necessary steps be taken to prevent
				leakage.
TEST 7. INDICATING THERMOMETERS ON PIPELINES-THERMOMETRIC
				RESPONSE
Reference.-Item 16p(D).
Application.
-To all indicating thermometers
				located on pipelines and used for determination of milk temperatures during
				pasteurization.
Frequency.
-Upon installation and once each 3
				months thereafter.
Criteria.
-Four seconds under specified
				conditions.
Apparatus.
-Test thermometer, stopwatch, water bath
				(10-gallon can), agitator, heat supply, and indicating thermometer from
				pasteurizer.
Method.
-By measuring the time required for the
				reading of the thermometer being tested to increase 12°F (7°C) through
				a specified temperature range (temperature range must include pasteurization
				temperature). The temperature used in the water or oil bath will depend upon
				the scale range of the thermometer to be tested.
Procedure.
-1. Immerse indicating thermometer in
				water or oil bath heated to a temperature at least 19°F (11°C) higher
				than minimum scale reading on indicating thermometer. Bath temperature should
				be higher than maximum pasteurization temperature for which thermometer is
				used.
2. Immerse indicating thermometer in bucket of cold water for
				several seconds to cool it.
Note.-Continuous agitation of water baths during the
				performance of steps 3, 4, and 5 is required. Elapsed time between end of step
				1, and beginning of step 3 should not exceed 15 seconds so hot water bath does
				not cool significantly.
3. Insert indicating thermometer in hot water or oil bath to
				proper bulb immersion depth.
4. Start stopwatch when indicating thermometer reads 19°F
				(11°C) below bath temperature.
5. Stop stopwatch when indicating thermometer reads 7°F
				(4°C) below bath temperature.
6. Record thermometric response time for office record.
Example.
-On a thermometer with a range of
				150°F to 175°F (66°C to 80°C) used at pasteurization
				temperatures of 161°F and 166°F (72°C and 75°C), a water bath
				of 170°F (77°C) could be used. 19°F (11°C) below 170°F
				(77°C) would be 151°F (66°C); 7°F (4°C) below 170°F
				(77°C) would be 163°F (73°C). Hence, after immersing the
				thermometer which has been previously cooled, in the 170°F (77°C) bath,
				the stopwatch is started when the thermometer reads 151°F (66°C) and
				stopped when it reads 163°F (73°C).
Note.-The test included the pasteurization temperature of
				161°F and 166°F (72°C and 75°C).
Corrective Action.
-If the response time should
				exceed 4 seconds, the thermometer should be replaced or returned for
				repair.
TEST 8. RECORDER/CONTROLLER-THERMOMETRIC
				RESPONSE
Reference.
-Item 16p(B).
Application.
-To all recorder/controllers used in
				connection with continuous-flow pasteurizers except those in which the
				flow-diversion device is located at the end of the cooler section.
Frequency.
-Upon installation and at least once
				each 3 months thereafter.
Criteria.
-Five seconds, under specified
				conditions.
Apparatus.
-Previously tested indicating
				thermometer on pasteurizers), stopwatch, water or oil bath (10-gallon milk
				can), agitator, heat supply.
Method.
-Measure the time interval between the
				instant when the recording thermometer reads 12°F (7°C) below the
				cut-in temperature and the moment of cut-in by the controller. This measurement
				is made when the sensing element is immersed in a rapidly agitated water or oil
				bath maintained at exactly 7°F (4°C) above the cut-in
				temperature.
Procedure.
-1. Check and, if necessary, adjust the
				pen-arm setting of the recording thermometer in the proper reference arc to
				agree with the indicating thermometer reading at pasteurization
				temperature.
2. Determine the cut-in temperature of controller (Test 10),
				either while in normal operation or by using a water or oil bath.
3. Remove sensing element and allow to cool to room
				temperature.
4 Heat water or oil bath to exactly 7°F (4°C) above the
				cut-in temperature while vigorously agitating bath to insure uniform
				temperature.
5. Immerse recorder/controller bulb in bath. Continue agitation
				during items 6. and 7. below.
6. Start stopwatch when the recording thermometer reaches a
				temperature of 12°F (7°C) below the cut-in temperature.
7. Stop stopwatch when the controller cuts in.
8. Record thermometric response time for office record.
Corrective Action.
-If the response should exceed 5
				seconds, the recorder/controller should be repaired.
TEST 9. SETTING OF CONTROL SWITCHES-REGENERATOR
				PRESSURE
Reference.
-Item 16p(D).
1. PRESSURE SWITCHES.
-Used to control operation of
				booster pumps.
Application.
-To all pressure switches controlling
				the operations of booster pumps on HTST pasteurizer systems employing
				regenerators.
Frequency.
-Upon installation, each 3 months
				thereafter, after any change in the booster pump or the switch circuit, and/or
				whenever the pressure switch seal is broken.
Criteria.
-The pump shall not operate unless there
				is at least a 1-pound pressure differential on the pasteurized milk side of the
				regenerator.
Apparatus.
-Sanitary pressure gauge and pneumatic
				testing device, for checking and adjusting pressure switch settings.
A simple inexpensive pneumatic testing device may be made from
				a discarded 2 inch-7BX sanitary tee, with two additional 13H nuts, one of which
				is provided with a 16A cap, drilled and tapped for a 1/2-inch galvanized iron
				nipple for the air connection. A hose connection is made to a compressed air
				source in the plant by means of a snap-on fitting. The air pressure can be
				controlled by an inexpensive pressure reducing valve (range 0-60 psig) followed
				by a 1/2-inch globe type bleeder valve connected into the side outlet of a
				1/2-inch tee installed between the pressure reducing valve and the testing
				device. The pressure switch to be tested is disconnected from the pasteurizer
				and connected to another of the outlets of the sanitary tee, and the pressure
				gauge is connected to the third outlet of the sanitary tee. By careful
				manipulation of the air pressure reducing valve and the air bleeder valve, the
				air pressure in the testing device may be regulated slowly and precisely. (In
				operating the device, care should be taken to avoid exposing the pressure
				switch and the sanitary pressure gauge to excessive pressure which might damage
				them. This can be done by first closing off the air pressure regulating valve
				and opening fully the bleeder valve; these may then be manipulated slowly to
				bring the air pressure in the testing device within the desired range.) A test
				light of proper voltage can be placed in series with the pressure switch
				contact and in parallel with the electrical load (booster pump starter) so the
				actuation point may be readily determined.
Method.
-Check and make adjustment of pressure
				switch so as to prevent the operation of the booster pump unless the pressure
				on the pasteurized milk side of the regenerator is greater by at least 1 psi
				than any pressure that may be generated on the raw side.
Procedure.
-(a) Determine maximum pressure of
				booster pump.
(1.) Install sanitary pressure gauge in tee at discharge of
				booster pump.
(2.) Operate the pasteurizer with water, with the
				flow-diversion device in forward-flow position, the metering pump operating at
				minimum speed possible, and the booster pump operating at its rated speed. If
				vacuum equipment is located between the raw outlet from the regenerator and the
				metering pump, it should be bypassed while this determination is made.
(3.) Note maximum pressure indicated by pressure gauge under
				these conditions.
(b) Check and set the pressure switch.
(1.) Install a sanitary pressure gauge of known accuracy on the
				pneumatic testing device to which the pressure switch sensing element should
				also be connected.
(2.) Remove the seal and cover to expose adjustment mechanism
				on pressure switch.
(3.) Operate the testing device and determine the pressure
				gauge reading at the cut-in point of the pressure switch which will light the
				test lamp. (If the switch is short circuited, the lamp will be lighted before
				air pressure is applied.)
(4.) The cut-in point should be adjusted, if necessary, so as
				to occur at a pressure gauge reading at least 1 psi greater than the maximum
				booster pump operating pressure, as determined under section a. of this method.
				Where adjustment is necessary, refer to manufacturer's instructions for
				adjusting procedure. After adjustment, recheck actuation point and readjust if
				necessary.
(5.) Replace cover and seal the pressure switch and restore
				sensing element to original location.
(6.) Record test results for the office record.
2. TIME DELAY SWITCHES.
-Used to control operation
				of booster pumps.
Application.
-To all time-delay switches
				controlling operation of booster pumps.
Frequency.
-Upon installation, after any change in
				the pump or relay circuit and whenever seal is broken.
Criteria.
-The booster pump shall not operate until
				the pasteurized milk has achieved a pressure at least 1 pound greater than the
				maximum pressure developed by the booster pump.
Apparatus.
-Accurate stopwatch, graduated at
				intervals not to exceed 0.2 of 1 second, pressure gauge or manometer.
Method.
-Reference: Dashiell, W. N.,
Use of
				Time Delay Relay To Control Booster Pump Operation.
Journal of Milk
				and Food Technology, 21:7. July 1958.
Procedure.
-a. Operate pasteurizers with water with
				the flow-diversion device in forward-flow position, metering pump operating at
				minimum speed, booster pump at rated speed. Vacuum equipment not operating or
				bypassed.
b. Determine the maximum pressure developed at the discharge of
				the booster pump. Following the determination of the height of the liquid
				level, add at least 3 feet to provide the 1-pound pressure differential
				equivalent of 0.7 feet of water column to compensate for difference in the
				specific gravity between water at 161°F (72°C) and raw milk at 40°F
				(4°C). The pasteurized liquid level must rise to the computed elevation,
				above the outlet level of the booster pump and be vented to the atmosphere at
				this or higher level.
c. Time the interval from the moment the forward flow is
				established until the pasteurized liquid level rises to the required elevation.
				The time measurement shall be made at the beginning of a run when no water is
				in the pasteurized product line. The booster pump shall not be
				operating.
d. The time delay relay shall be installed in the circuit,
				interlocked with the metering pump, forward-flow of the flow-diversion device
				and the booster pump. Adjust the time delay setting to provide the time
				interval. Check the setting several times. Seal the time delay relay.
e. Record for permanent office record.
Corrective Action.
-Adjust pasteurized milk pipe
				to proper elevation. If time delay relay is not accurate, return for
				repair.
3. PRESSURE GAUGES.
-Used with booster pump
				operations
Application.
-To all required pressure gauges
				used to measure relative raw milk and pasteurized milk pressure in HTST
				regenerators.
Frequency.
-Upon installation, each 3 months
				thereafter, and whenever the gauges are adjusted or repaired.
Criteria.
-Required pressure gauges shall be
				accurate.
Apparatus.
-Identical testing device used to check
				proper operation of pressure switch (Test 9, 1).
A pressure gauge of known accuracy is connected to one outlet
				of the test apparatus. The gauge being checked is connected to the second
				outlet of the sanitary tee. Air is bled into the system through the third
				outlet and comparative readings made. Record test results for office
				record.
Corrective Action.
-Inaccurate gauges should be
				returned to the factory for repair. It is not recommended that the plant
				operator attempt the adjustment of pressure gauges.
4. DIFFERENTIAL PRESSURE CONTROLLER
Application.
-To all differential pressure
				controllers used to control operation of booster pumps on HTST and HHST
				systems, or used to control operation of flow-diversion devices on HHST systems
				when no vacuum breaker is located downstream from the holding tube.
Frequency.
-Upon installation, each 3 months
				thereafter, and whenever the differential pressure controller is adjusted or
				repaired.
Criteria.
-The booster pump shall not operate or
				the pasteurizer shall not operate in forward flow unless the product pressure
				in the pasteurized side of the regenerator is at least 1 psi greater than the
				product pressure in the raw side of the regenerator. When the differential
				pressure controller is used to control the flow-diversion device on HHST
				systems, and improper pressures occur in the regenerator, the flow-diversion
				device shall move to the diverted-flow position and remain in diverted flow
				until proper pressures are reestablished in the re-generator and all
				product-contact surfaces between the holding tube and flow-diversion device
				have been held at or above the required pasteurization temperature,
				continuously and simultaneously for at least the required pasteurization time
				as defined in section
				2.2(a)  of this
				Title.
Apparatus.
-A sanitary pressure gauge and a
				pneumatic testing device described under PRESSURE SWITCHES (Test 9,1) above can
				be used for checking and adjusting the differential pressure switch
				setting.
Method.
-The differential pressure switch is
				checked and adjusted to prevent operation of the booster pump, or prevent
				forward flow, unless the product pressure in the pasteurized side of the
				regenerator is at least 1 psi greater than the pressure in the raw side of the
				regenerator.
Procedures.
-a. Loosen the process connection at
				both pressure sensors and wait for any liquid to drain through the loose
				connections. Both pointers should be within 0.5 psi of 0 psig. If not, adjust
				pointer(s) to read 0 pounds psig.
b. Remove both sensors from the process and mount them in a
				tee, either at the discharge of the booster pump, or connected to the pneumatic
				testing device. Note the separation between the two pointers. The change in
				elevations of the sensors will have caused some change in the zero readings.
				Turn on the booster pump switch and depress the test push button to operate the
				booster pump. If the pneumatic testing device is used in lieu of the booster
				pump, adjust air pressure to the normal operating pressure of the booster pump.
				Note that the pointer separation is within 1 psi of that observed before
				pressure was applied. If not, the instrument requires adjustment or
				repair.
c. Return the pressure sensors to their normal process
				locations and turn off the booster pump switch. Manually move and hold the
				white pointer (raw side of the regenerator) at the normal operating pressure of
				the booster pump. Press the test push button while manually moving the orange
				pointer (pasteurized side of the regenerator) upscale until the pilot light
				turns on, then slowly move the orange pointer downscale until the pilot light
				turns off. The pilot light should not turn on until the orange pointer is at
				least 2 psi higher than the white pointer, and the pilot light should turn off
				when the orange pointer is no less than 2 psi higher than the white pointer. If
				necessary, adjust the differential setting. The 2 psi differential represents
				the sum of the 1 psi differential required between raw and pasteurized product
				in the regenerator, plus the 1 psi imprecision permitted between the two
				pressure sensors.
d. Seal the instrument and record test results for the office
				record.
TEST 10. MILK-FLOW CONTROLS-MILK TEMPERATURES AT CUT-IN
				AND CUT-OUT
References.
-Item 16p(B), 16p(D).
Milk-flow controls shall be tested for milk temperature at
				cut-in and cut-out by one of the following applicable tests at the frequency
				prescribed:
1. Application.
-All recorder/controllers used in
				connection with HTST pasteurizers except those in which the flow-diversion
				device is located at the end of the cooler section.
Frequency.
-Upon installation and quarterly by the
				regulatory agency; daily by the plant operator.
Criteria.
-No forward flow until pasteurization
				temperature has been reached. Flow diverted before temperature drops below
				minimum pasteurization temperature.
Apparatus.
-No supplemental materials
				needed.
Method.
-By observing the actual temperature of the
				indicating thermometer at the instant forward flow starts (cut-in) and stops
				(cut-out).
Procedure.
-a. Cut-in temperature.
(1.) While milk or water is completely flooding the sensing
				element of the recorder/controller and the indicating thermometer, increase the
				heat gradually so as to raise the temperature of the water or milk at a rate
				not exceeding 1°F (0.5°C) every 30 seconds.
(2.) Observe the indicating thermometer reading at the moment
				the forward flow starts (i.e., flow-diversion device moves). Observe that the
				frequency pen reading is synchronized with the recording pen on the same
				reference arc.
(3.) Record the indicating thermometer reading on the recorder
				chart: inscribe initials. The regulatory agency shall record test
				findings.
b. Cut-out temperature.
(1.) After the cut-in temperature has been determined and while
				the milk or water is above the cut-in temperature, allow the water to cool
				slowly at a rate not exceeding 1°F (0.5°C) per 30 seconds. Observe
				indicating thermometer reading at the instant forward flow stops.
(2.) Record the indicating thermometer reading on the recorder
				chart.
Corrective Action.
-Should the reading be below the
				minimum pasteurization temperature, the cut-in and cut-out mechanism and/or the
				differential temperature mechanism should be adjusted to obtain proper cut- in
				and cut-out temperatures by repeated tests. When compliance is achieved, seal
				the controller mechanism.
2. Application.
-All HHST pasteurizers using
				indirect heating.
Frequency.
-Upon installation, and every 3 months
				thereafter; whenever the thermal controller seal is broken.
Criteria.
-The pasteurizer shall not operate in
				forward flow unless pasteurization temperature has been achieved. The product
				flow shall be diverted at a temperature no lower than the chosen pasteurization
				standard.
Apparatus.
-No supplemental materials
				needed.
Method.
-The cut-in and cut-out temperatures are
				determined by observing the actual temperature in the constant temperature bath
				at which the two sensing elements signal for forward flow (cut-in) and diverted
				flow (cut-out).
Procedures.
-a. Wire the test lamp in series with
				the control contacts of the sensing element (holding tube). Immerse this
				sensing element in the constant temperature bath. Raise the bath temperature at
				a rate not exceeding 1°F (0.5°C) every 30 seconds. Observe the
				temperature reading at the cut-in temperature. Record the temperature for the
				office record.
b. After the cut-in temperature has been determined and while
				the bath is above the cut-in temperature, allow the bath to cool slowly at a
				rate not exceeding 1°F (0.5°C) per 30 seconds. Observe the temperature
				reading on the controller when the test lamp goes out (cut-out temperature).
				Determine that the cut-out temperature on the thermal limit controller is
				equivalent to or greater than the chosen pasteurization standard. Where
				adjustment is necessary, refer to manufacturer's instructions. After
				adjustment, repeat the procedure above and when the results are satisfactory,
				record results for the office records.
c. Repeat the procedure for the other sensing element,
				(flow-diversion device). When proper cut-out temperature has been verified for
				both sensing elements, seal the controller system.
3. Application.
-All HHST pasteurizers using direct
				contact heating.
Frequency.
-Upon installation, and every 3 months
				thereafter; whenever the thermal limit controller seal is broken.
Criteria.
-The pasteurizer shall not operate in
				forward flow unless pasteurization temperature has been achieved. The product
				flow shall be diverted at a temperature no lower than the chosen pasteurization
				standard.
Apparatus.
-No supplemental materials
				needed.
Method.
-The cut-in and cut-out temperatures are
				determined by observing the actual temperature in the constant temperature bath
				at which each of the three sensing elements signals for forward flow (cut-in)
				and diverted flow (cut-out).
Procedures.
-a. Wire the test lamp in series with
				the control contacts of the sensing element (the holding tube). Immerse this
				sensing element in the constant temperature bath. Raise the bath temperature at
				a rate not exceeding 1°F (0.5°C) every 30 seconds. Observe the
				temperature reading on the controller when the test lamp lights (cut-in
				temperature). Record the temperature for the office record.
b. After the cut-in temperature has been determined and while
				the bath is above the cut-in temperature, allow the bath to cool slowly at a
				rate not exceeding 1°F (0.5°C) per 30 seconds. Observe the temperature
				reading on the controller when the test lamp goes out (cutout temperature).
				Determine that the cut-out temperature on the thermal limit controller is
				equivalent to or greater than the chosen pasteurization standard. Where
				adjustment is necessary, refer to manufacturer's instructions. After
				adjustment, repeat the procedure above and when the results are satisfactory,
				record results for the office record.
c. Repeat the procedure for the other two sensing elements,
				i.e., the vacuum chamber and flow-diversion device. Rewire the test lamp in
				series with the control contacts from each sensing element, respectively. When
				proper cut-out temperatures have been verified for all three sensing elements,
				seal the controller system.
TEST 11. CONTINUOUS FLOW HOLDERS-HOLDING
				TIME
Reference.
-Item 16p(B).
Continuous flow holders shall be tested for holding times by
				one of the applicable tests.
1. Application.
-To all HTST pasteurizers employing
				a holding time of 15 seconds or longer.
Frequency.
-As set forth in application 2
				below.
Criteria.
-Every particle of milk shall be held for
				at least 15 seconds in both the forward- and diverted-flow positions.
Apparatus.
-Electrical conductivity measuring
				device, Appendix 4 (I.) capable of detecting change in conductivity, equipped
				with standard electrodes; table salt (sodium chloride), 50 ml. syringe;
				stopwatch; suitable container for salt solution.
Method.
-The holding time is determined by timing
				the interval for an added trace substance to pass through the holder. Although
				the time interval of the fastest particle of milk is desired, the conductivity
				test is made with water. The results found with water are converted to the milk
				flow time by formulation since a pump may not deliver the same amount of milk
				as it does water.
Procedure.
-a. Examine the entire system to insure
				that all flow promoting equipment is operating at maximum capacity and all flow
				impeding equipment is so adjusted or bypassed as to provide the minimum of
				resistance to the flow. There shall be no leakage on the suction side of the
				timing pump.
b. Adjust variable speed pump to its maximum capacity
				(preferably with a new belt and full size impellers). Check homogenizers for
				seals and/or gears or pulley identification.
c. Install one electrode at the inlet to the holder and the
				other electrode in the holder outlet. Close the circuit to the electrode
				located at the inlet to the holder.
d. Operate the pasteurizer using water at pasteurization
				temperature, with flow-diversion device in forward-flow position.
e. Quickly inject 50 ml. of saturated sodium chloride solution
				into the holder inlet.
f. Start the stopwatch with the first movement of the indicator
				of a change in conductivity. Open the circuit to the inlet electrode and close
				the circuit to the electrode at the outlet of the holder.
g. Stop the stopwatch with the first movement of the indicator
				of a change in conductivity.
h. Record results
i. Repeat the test six or more times, until six successive
				results are within 0 5 seconds of each other. The average of these six tests is
				the holding time for water in forward flow. When consistent readings cannot be
				obtained, purge the equipment, check instruments and connections, and check for
				air leakage on suction side. Repeat tests. Should consistent readings not be
				obtained, use the fastest time as the holding time for water.
j. Repeat steps d. through i. for testing time on water in
				diverted flow.
k. With the pump at the same speed and equipment adjusted as in
				a. above, time the filling of a 10-gallon can with a measured weight of water
				using the discharge outlet with the same head pressure as in normal operation.
				Average the time of several trials. (Since flow rates of the large capacity
				units make it very difficult to check by filling a 10-gallon can, it is
				suggested that a calibrated tank of considerable size be used.)
l. Repeat procedure k. using milk.
m. Compute the holding time for milk from the following formula
				by weight, using the average specific gravity. Compute separately for forward
				flow and diverted flow.
Holding time for milk=(1.032(TMw)/Ww) (by weight), in
				which-
1.032 = specific gravity for milk;
T = average holding time for water;
Mw = average time required to deliver a measured weight of
				milk.
Ww = average time required to deliver an equal weight of
				water.
n. Record results for office record.
Corrective Action.
-When the computed holding time
				for milk is less than that required either in forward flow or diverted flow,
				the speed of the timing pump shall be reduced or adjustment made in the holding
				tube, and the timing test repeated until satisfactory holding time is achieved.
				Should an orifice be used to correct the holding time in diverted flow, there
				should be no excessive pressure exerted on the underside of the valve seat of
				the flow-diversion device. Governors shall be sealed on motors that do not
				provide a constant speed as provided in Item 16p(B) §
								2.46  b.6.ii.
2. Application.
-To all HHST pasteurizers using
				indirect heating.
Frequency.-Upon installation and quarterly thereafter, whenever
				seal on speed setting is broken: any alteration is made affecting the holding
				time, the velocity of the flow (such as replacement of pump, motor, belt, drive
				or driven pulleys, or decrease in number of HTST plates) or the capacity of
				holding tube: or whenever a check of the capacity indicates a speedup. Except
				that semiannually two canfill measurements may be substituted for electrical
				conductivity measurements. The canfill measurements shall be conducted as
				provided in Item k. of Test 11 of this Appendix.
Criteria.
-Every particle of product shall be held
				for the minimum holding time in both the forward-and diverted-flow
				positions.
Apparatus.
-No supplemental materials
				needed.
Method.
-Fully developed laminar flow is assumed
				and holding tube length is calculated. An experimental determination of pumping
				rate is required; this is accomplished by determining the time required for the
				pasteurizer to fill a vessel of known volume, converting these data by division
				to obtain flow rate in gallons per second, and multiplying this value by the
				proper number in Table 8 of this paragraph to obtain the required length of
				holding tube. Holding tube lengths for HHST pasteurizers with indirect heating
				for a pumping rate of 1 gallon/second are:
TABLE 8
Tubing size
							 (inches)
Holding time (seconds)
1
11/2
2
21/2
3
Holding tube length
							 (inches)
1
723.0
300.0
168.0
105.0
71.4
0.5
362.0
150.0
84.0
52.4
35.7
0.1
72.3
30.0
16.8
10.5
7.14
0.05
36.2
15.0
8.4
5.24
3.57
0.01
7.23
3.0
1.68
1.05
0.714
Procedures.
-a. Examine the entire system to
				ensure that all flow promoting equipment is operating at maximum capacity and
				all flow impeding equipment is so adjusted or bypassed to provide the minimum
				of resistance to the flow. This means that in-line filters must be removed,
				booster pumps must be in operation, and vacuum equipment in the system must be
				operating at a maximum vacuum. Also, before the tests are begun, the
				pasteurizer should be operated at maximum flow for a sufficient time to purge
				air from the system (about 15 minutes) and pipe connections on the suction side
				of the metering pump should be made tight enough to exclude entrance of air.
				With the pasteurizer operating with water, adjust the metering pump to its
				maximum capacity, preferably with a new belt and full-size impellers.
b. Determine that no flow exists in the diverted line, and
				measure the time required to deliver a known volume of water at the
				forward-flow discharge line. Repeat the test at least once to determine that
				the measurements are consistent.
c. Repeat the steps in paragraphs a. and b. of this procedure
				in diverted flow by collecting the effluent at the discharge of the divert
				line.
d. Select the greatest flow rate (shortest delivery time for
				the known volume) and calculate the flow rate in gallons per second by dividing
				the known volume by the time required to collect the known volume. Multiply
				this value with the appropriate value in Table 8 to determine the required
				holding tube length.
e. Determine the number and type of fittings in the holding
				tube and convert these to equivalent lengths of straight pipe with the use of
				Table 9 of this paragraph. Determine the total length of the holding tube by
				adding the equivalent lengths of the fittings to the measured straight lengths
				of pipe. Record the number and type of fittings, the number and length of
				straight pipes, and the holding tube configuration for the office record. If
				the temperature sensor is located at the beginning of the holding tube, the
				holding tube shall be protected against heat loss by material that is
				impervious to water.
TABLE 9 Centerline Distances of 3-A
				Fittings
Fitting size
							 (inches)
3-A designation
1
11/2
2
21/2
3
Centerline distance
							 (inches)
2C 90° bend
3.4
4.8
6.2
8.0
9.7
2CG 90° bend
3.1
4.5
5.8
7.6
9.3
2F 90° bend
3.4
4.8
6.2
8.0
9.7
2FG 90° bend
3.1
4.5
5.8
7.6
9.3
2E 90° bend
3.4
4.8
6.2
8.0
9.7
2EG 90° bend
3.2
4.6
6.0
7.7
9.4
Alternate procedure.
-For pasteurizers of large
				capacity, the method of measuring flow rate at the discharge of the pasteurizer
				is inconvenient, and the following alternate test procedure may be used. Remove
				the divert line from the raw-product supply tank, and turn off the product pump
				feeding the raw-product supply task. Suspend a sanitary dip stick in the
				raw-product supply tank, and operate the pasteurizer at maximum capacity.
				Record the time required for the water level to move between two graduations on
				the dip stick. The volume of water is calculated from the dimensions of the
				raw-product supply tank and the drop in water level. Flow rate is determined as
				follows: Divide the volume of water removed from the raw-product supply tank by
				the time required to remove it.
Corrective action.
-If the length of the holding
				tube is shorter than the calculated length, reseal the metering pump at a
				slower maximum speed, or lengthen the holding tube, or both, and repeat the
				above determination.
3. Application.
-To all HHST pasteurizers using
				direct contact heating.
Frequency.
-When installed and semiannually
				thereafter; whenever seal on the speed setting is broken; whenever any
				alteration is made affecting the holding time, the velocity of the flow, e.g.,
				replacement of pump, motor, belt, driver or driven pulley, or decrease in the
				number of heat exchange plates, or the capacity of the holding tube; whenever a
				check of the capacity indicates a speedup.
Apparatus.
-No supplemental materials
				needed.
Criteria.
-Every particle of product shall be held
				for the minimum holding time in both forward- and diverted-flow
				positions.
Method.
-Fully developed laminar flow and a
				temperature increase by steam injection of 120°F (67C) are assumed, the
				temperature-time standard is chosen by the processor, and the required holding
				tube length is calculated from an experimental determination of pumping
				rate.
Procedures.
-a. Examine the entire system to
				ensure that all flow promoting equipment is operating at a maximum capacity and
				all flow impeding equipment is so adjusted or bypassed as so provide the
				minimum resistance to the flow. Remove in-line filters, make certain booster
				pumps are operating and that vacuum equipment in the system is operating at
				maximum vacuum. Also, before the tests are begun, operate the pasteurizer at
				maximum flow for a sufficient time to purge the air from the system (about 15
				minutes) and tighten pipe connections on the suction side of the metering pump
				to exclude entrance of air. With the pasteurizer operating on water, adjust the
				metering pump to its maximum capacity. Determine that no flow exists in the
				diverted line, and measure the time required to deliver a known volume of water
				at the discharge of the pasteurizer in forward flow. Repeat the test at least
				twice to determine that the measurements are consistent.
b. Repeat the last step (a. above) in diverted flow by
				collecting the effluent at the discharge of the divert line. Select the
				greatest flow rate, the shortest delivery time for the known volume, and
				calculate the flow rate in gallons per second by dividing the known volume by
				the time required to collect the known volume. Multiply this value, gallons per
				second, with the appropriate value in Table 10 of this paragraph to determine
				the required holding tube length. Holding tube lengths for direct contact
				heating pasteurizers with a pumping rate of 1 gallon/second are:
TABLE 10
Tubing size
							 (inches)
Holding time (seconds)
1
11/2
2
21/2
3
Holding tube length
							 (inches)
1
810.0
336.0
188.0
118.0
80.0
0.5
405.0
168.0
94.0
59.0
40.0
0.1
81.0
33.6
18.8
11.8
8.0
0.05
40.5
16.8
9.40
5.90
4.0
0.01
8.10
3.36
1.88
1.18
0.8
c. Determine the number and type of fittings in the holding
				tube, and convert these to equivalent lengths of straight pipe with the use of
				Table 9.
Determine the total length of the holding tube by adding the
				equivalent lengths of the fittings to the measured lengths of straight pipe. If
				the actual holding tube length is equivalent to or greater than the required
				holding tube length, record the number and type of fittings, the number and
				length of straight pipes, and the holding tube configuration, for the office
				record. Make sure that the holding tube slopes upward at least 0.25 inch per
				foot. The holding tube shall also be protected against heat loss with
				insulation that is impervious to water if the temperature sensor is located at
				the beginning of the holding tube.
Alternate procedure.
-For pasteurizers of large
				capacity, the method of measuring flow rate at the discharge of the pasteurizer
				is inconvenient, and the following alternate test procedure may be used. Remove
				the divert line from the raw product supply tank, and turn off the product pump
				feeding the raw-product supply tank. Suspend a sanitary dip stick in the
				raw-product supply tank, and operate the pasteurizer at maximum capacity.
				Record the time required for the water level to move between two graduations on
				the dip stick. Calculate the volume of water from the dimensions of the
				raw-product supply tank and the drop in water level. Determine flow rate as
				follows: Divide the volume of water, in gallons, removed from the raw-product
				supply tank by the time, in seconds, required to remove it. Then use Table 10
				to calculate the required holding tube length.
Corrective action.
-If the length of the holding
				tube is shorter than the calculated length, reseal the metering pump at a
				slower maximum speed, or lengthen the holding tube, or both, and repeat the
				procedure.
TEST 12. THERMAL LIMIT CONTROLLER FOR CONTROL-SEQUENCE
				LOGIC
References.
-Items 16p(B), 16p(D).
Thermal limit controllers used with HHST systems that have the
				flow-diversion device located downstream from the regenerator and/or cooler
				shall be tested by one of the following applicable tests at the frequency
				specified.
1. Application.
-To all HHST pasteurizers using
				indirect heating.
Frequency.
-Upon installation, and every 3 months
				thereafter.
Criteria.
-The pasteurizer shall not operate in
				forward flow until the product surfaces downstream from the holding tube have
				been sanitized on start up; surfaces shall be exposed to fluid at
				pasteurization temperature for at least pasteurization time. If the product
				temperature falls below the pasteurization standard in the holding tube,
				forward flow shall not be reachieved until the product surfaces downstream from
				the holding tube have been resanitized.
Apparatus.
-A constant temperature bath of water or
				oil and the test lamp from the pneumatic testing device described in Test 9, 1
				can be used to check the control-sequence logic of the thermal limit
				controller.
Method.
-The control-sequence logic of the thermal
				limit controller is determined by monitoring the electric signal from the
				thermal limit controller during a series of immersions and removals of the two
				sensing elements from a bath heated above the cut-in temperature.
Procedures.
-a. Heat a constant temperature water
				or oil bath a few degrees above the cut-in temperature on the thermal limit
				controller. Wire the test lamp in series with the signal from the thermal limit
				controller to the flow-diversion device. If some processors have time delays
				built into their control logic in excess of that required for public health
				reasons, bypass these timers or account for their effect in delaying forward
				flow.
b. Immerse the sensing element of the flow-diversion device in
				the bath, which is above the cut-in temperature. The test lamp should remain
				unlighted, i.e., diverted flow. Leave the sensing element in the bath
c. Immerse the sensing element from the holding tube in the
				bath. The test lamp should light up, i.e., forward flow after a minimum time
				delay of second.
d. Remove the sensing element of the flow-diversion device from
				the bath. the test lamp should remain lighted, i.e., forward flow.
e. Remove the holding tube sensing element from the bath The
				test lamp should go out immediately, i.e., diverted flow.
f. Reimmerse the sensing element of the holding tube in the
				bath. The test lamp should remain unlighted, i.e., diverted flow.
Corrective action.
-If the control sequence logic
				of the thermal unit controller does not follow this pattern, the instrument
				shall be required to conform to this logic.
2. Application.
-To all HHST pasteurizers using
				direct contact heating.
Frequency.
-Upon installation, and every 3 months
				thereafter.
Criteria.
-The pasteurizer shall not operate in
				forward flow until the product surfaces downstream from the holding tube have
				been sanitized on start up; surfaces shall be exposed to fluid at
				pasteurization temperature for at least pasteurization time. If the product
				temperature falls below the pasteurization standard in the holding tube,
				forward flow shall not be reachieved until the product surfaces downstream from
				the holding tube have been resanitized.
Apparatus.
-A constant temperature bath of water or
				oil and the test lamp from the pneumatic testing device described in Test 9, 1
				can be used to check the control-sequence logic of the thermal limit
				controller.
Method.
-The control-sequence logic of the thermal
				limit controller is determined by monitoring the electric signal from the
				thermal limit controller during a series of immersions and removals of the
				three sensing elements from a bath heated above the cut-in temperature.
Procedures.
-a. Heat a water or oil bath to a
				constant temperature, a few degrees above the cut-in temperature on the thermal
				limit controller. Wire the test lamp in series with the signal from the thermal
				limit controller to the flow-diversion device. If some processors have time
				delays built into their control logic in excess of that required for public
				health reasons, bypass these timers or account for their effect in delaying
				forward flow. Before performing this test, make sure the pressure switches
				which must be closed to achieve forward flow, have also been bypassed.
b. Immerse the sensing element from the flow-diversion device,
				in the bath, which is above the cut-in temperature. The test lamp should remain
				unlighted, i.e., diverted flow. Remove this sensing element from the
				bath.
c. Immerse the sensing element from the vacuum chamber, in the
				bath. The test lamp should remain unlighted, i.e., diverted flow. Remove the
				sensing element from the bath.
d. Immerse two sensing elements, from the vacuum chamber and
				flow-diversion device, in the bath. The test lamp should remain unlighted,
				i.e., diverted flow. Leave the two sensing elements in the bath.
e. Immerse the third sensing clement, from the holding tube in
				the bath. The test lamp should light up, i.e., forward flow, after a minimum
				time delay of 1 second.
f. Remove one sensing element, the flow-diversion device, from
				the bath. The test lamp should remain lighted, i.e., forward flow.
g. Remove another sensing element, the vacuum chamber, from the
				bath. The test lamp should remain lighted, i.e., forward flow.
h. Remove the last sensing element, the holding tube, from the
				bath. The test lamp should go out, i.e., diverted flow, immediately.
i. Reimmerse the sensing element, holding tube, in the bath.
				The test lamp should remain unlighted, i.e., diverted flow.
Corrective action.
-If the control-sequence logic
				of the thermal limit controller does not follow the pattern set out in the
				procedures section, the instrument shall be rewired to conform to this
				logic.
TEST 13. SETTING OF CONTROL SWITCHES FOR PRODUCT PRESSURE
				IN THE HOLDING TUBE
Reference.
-Item 16p(B).
Application.
-To all HHST pasteurizers using direct
				contact heating.
Frequency.
-Upon installation, and every 3 months
				thereafter; whenever the pressure switch seal is broken; and whenever the
				operating temperature is changed.
Criteria.
-The pasteurizer shall not operate in
				forward flow unless the product pressure in the holding tube is at least 10 psi
				above the boiling pressure of the product.
Apparatus.
-A sanitary pressure gauge and a
				pneumatic testing device described in Test 9,1 can be used for checking and
				adjusting the pressure switch setting.
Method.
-The pressure switch is checked and
				adjusted so as to prevent forward flow unless the product pressure in the
				holding tube is at least 10 psi above the boiling pressure of the
				product.
Procedure.
-From Figure 31 determine the pressure
				switch setting necessary for the operating temperature (not the diversion
				temperature) being used in the process. Install the sanitary pressure gauge of
				known accuracy and the pressure switch sensing element on the pneumatic testing
				device. Remove the seal and cover to expose the adjustment mechanism on the
				pressure switch. Place the test lamp in series with the pressure switch
				contacts or use some other method to monitor the cut-in signal. Apply air
				pressure to the sensing element, and determine the pressure gauge reading at
				the cut-in point of the switch which will light the test lamp. If the switch is
				short circuited, the lamp will be lighted before air pressure is applied.
				Determine that the cut-in pressure on the switch is equivalent to or greater
				than the required pressure from Figure 31. Where adjustment is necessary, refer
				to manufacturer's instruction. After adjustment, repeat the procedure set out
				in this paragraph. When the results are satisfactory, seal the pressure switch
				setting and record the results for the office record. For each operating
				temperature on HHST pasteurizers using direct contact heating, the product
				pressure switch setting is as follows:
Click to view
				image
TEST 14. SETTING OF CONTROL SWITCHES FOR DIFFERENTIAL
				PRESSURE ACROSS THE INJECTOR
Application.
-To all HHST pasteurizers using direct
				contact heating.
Frequency.
-Upon installation and every 3 months
				thereafter; whenever the differential pressure controller seal is
				broken.
Criteria.
-The pasteurizer shall not operate in
				forward flow unless the product pressure drop across the injector is at least
				10 psi.
Apparatus.
-A sanitary pressure gauge and a
				pneumatic testing device described in Test 9,1 can be used for checking and
				adjusting the differential pressure controller.
Method.
-Check the differential pressure switch and
				adjust it so as to prevent forward flow unless the differential pressure across
				the injector is at least 10 psi.
Procedure.
-Remove both pressure sensing elements
				from their original locations on the pasteurizer, install the sanitary pressure
				gauge of known accuracy and the pressure sensing element that is installed
				prior to steam injection on the pneumatic testing device. Leave the other
				pressure sensing element open to the atmosphere but at the same height as the
				sensing element connected to the pneumatic testing device. Wire the test lamp
				in series with the microswitch of the differential pressure controller or use
				the method provided by the instrument manufacturer to monitor the cut-in
				signal. Apply air pressure to the sensing element and determine the pressure
				gauge reading at the cut-in point of the differential pressure switch that will
				light the test lamp. Determine that the differential pressure cut-in on the
				controller is at least 10 psi. Where adjustment is necessary, refer to
				manufacturer's instructions. After adjustment, repeat the procedure set forth
				in this paragraph. When the results are satisfactory, seal the instrument and
				record the results for the office record.