Appendix 9.  


THERMOMETER SPECIFICATIONS
(cf. Part 3)
INDICATING THERMOMETERS LOCATED ON PASTEURIZATION PIPELINES
Type.—Mercury-actuated; direct-reading; contained in corrosion-resistant case which protects against breakage and permits easy observation of column and scale; filling above mercury, nitrogen, or equally suitable gas.
Magnification of Mercury Column. —To apparent width of not less than 0.0625 of an inch.
Scale. —Shall have a span of not less than 25 Fahrenheit degrees (14 Celsius degrees), including the pasteurization temperature plus and minus 5°F (3°C); graduated in 0.5°F (0.25°C) divisions with not more than 8 Fahrenheit degrees (4 Celsius degrees) per nch of scale; protected against damage at 220°F (105°C).
Accuracy.—Within 0.5°F (0.25°C), plus or minus throughout specified scale span. (Appendix 10, Test 1)
Stem Fittings.—Pressure-tight seat against inside wall of fittings; no threads exposed to product; distance from underside of ferrule to top of the sensitive portion of bulb not less than 3 inches.
Thermometric Response.—When the thermometer is at room temperature and then is immersed in a well-stirred water bath 19°F (11°C) or less above the pasteurization temperature, the time required for the reading to increase from water bath temperature minus 19°F (11°C) to water bath temperature minus 7°F (4°C) shall not exceed 4 seconds. (Appendix 10, Test 6)
Bulb.—Corning normal, or equally suitable thermometric glass.
RECORDER/CONTROLLERS FOR CONTINUOUS PASTEURIZERS
Case. —Moistureproof under normal operating conditions in pasteurization plants.
Chart Scale.—Shall have a span of not less than 30 Fahrenheit degrees (17 Celsius degrees), including the temperature at which diversion is set, plus and minus 12°F (7°C), graduated in temperature scale divisions of 1°F (0.5°C) spaced not less than 0.0625 of an inch apart at the diversion temperature, plus or minus 1°F (0.5°C): Provided, That temperature-scale divisions of 1°F (0.5°C) spaced not less than 0.040 of an inch apart are permitted when the ink line is thin enough to be easily distinguished from the printed line, graduated in time scale divisions of not more than 15 minutes, having an equivalent 15 minute chord or straight-line length of not less than 0.25 of an inch at the diversion temperature, plus or minus 1°F (0.5°C).
Temperature Accuracy. —Within 1°F (0.5°C), plus or minus, at the temperature at which the controller is set to divert, plus and minus 5°F (3°C). (Appendix 10, Test 2)
Power Operated. —All recorder/controllers for continuous pasteurization shall be electrically operated.
Pen-Arm Device.—Easily accessible; simple to adjust.
Pen and Chart Paper.—Pen designed to give line not over 0.025 of an inch wide; easy to maintain.
Temperature Sensing Device.—(Bulb, tube, spring, thermister) protected against damage at temperature of 220°F (105°C).
Submerged Stem Fitting.—Pressure-tight seat against inside wall of pipe; no threads exposed to products; location from underside of ferrule to the sensitive portion of the bulb not less than 3 inches.
Chart Speed. —A circular chart shall make one revolution in not more than 12 hours. Two charts shall be used if operations extend beyond 12 hours in 1 day. Circular charts shall be graduated for a maximum record of 12 hours. Strip-charts may show a continuous recording over a 24-hour period.
Frequency Pen. —The recorder/controller shall be provided with an additional pen-arm for recording, on the outer edge of the chart, the record of the time at which the flow-control device is in the forward-flow, diverted-flow, or stopped position. The chart time line shall correspond with the reference arc, and the recording pen shall rest upon the time line matching the reference arc.
Controller. —Actuated by same sensor at recorder pen but cut-in and cut-out response independent of pen-arm movement.
Controller Adjustment.—Mechanism for adjustment of response temperature simple, and so designed that the temperature setting cannot be changed or the controller manipulated without detection.
Thermometric Response. —With the recorder/controller bulb at room temperature and then immersed in a well stirred water or oil bath at 7°F (4°C) above the cut-in point, the interval between the moment when the recording thermometer reads 12°F (7°C) below the cut-in temperature and the moment of power cut-in shall be not more than 5 seconds. (Appendix 10, Test 7)
Chart Support Drive.—The rotating chart support drive shall be provided with a pin to puncture the chart in a manner to prevent its fraudulent rotation.
INDICATING THERMOMETERS USED IN STORAGE TANKS
Scale Range.—Shall have a span not less than 50 Fahrenheit degrees (28 Celsius degrees) including normal storage temperatures plus and minus 5°F (3°C) with extension of scale on either side permitted; graduated in not more than 2°F (1°C) divisions.
Temperature Scale Divisions. —Spaced not lest than 0.0625 of an inch apart between 32°F and 55°F (0°C and 13°C).
Accuracy. —Within 2°F (1°C) plus or minus, throughout the specified scale range.
Stem Fitting.—Pressure-tight seat or other suitable sanitary fittings. No threads exposed.
RECORDING THERMOMETERS USED IN STORAGE TANKS
Case.—Moisture-proof under operating conditions in processing plants.
Scale.—Shall have a scale span of not less than 50 Fahrenheit degrees (28 Celsius degrees), including normal storage temperature plus and minus 5°F (3°C), graduated in not more than 2°F (1°C) divisions with not more than 40 Fahrenheit degrees (23 Celsius degrees) per inch of scale; graduated in time scale divisions of not more than 1 hour having a chord or straight line length of not less than 0.125 of an inch at 40°F (5°C). Chart must be capable of recording temperatures up to 180°F (83°C). (Span specifications do not apply to extensions beyond 100°F (38°C).
Temperature Accuracy. —Within 2°F (15°C) plus or minus, between specified range limits.
Pen-Arm Setting Device.—Easily accessible; simple to adjust.
Pen and Chart Paper.—Designed to give a line not over 0.025 of an inch thick when in proper adjustment; easy to maintain.
Temperature Sensor.—Protected against damage at 212°F (100°C).
Stem Fitting.—Pressure-tight seat or other suitable sanitary fitting. No threads exposed.
Chart Speed. —The circular chart shall make one revolution in not more than 7 days and shall be graduated for a maximum record of 7 days. Strip chart shall move not lest than 1 inch per hour and may be used continuously for 1 calendar month.
RECORDING THERMOMETERS ON MECHANICAL CLEANING SYSTEMS
Location.—Temperature sensor in the return line downstream from processing equipment and all lines included in the cleaning-in-place process.
Case.—Moisture-proof under operating conditions.
Scale.—Shall have a range of 60°F to 180°F (16°C to 83°C), with extensions of scale on either side permissible; graduated in time-scale divisions of not more than 15 minutes. Above 110°F (44°C), the chart is to be graduated in divisions of not more than 2F (1C) spaced not lest than 0.0625 of an inch apart: Provided, That temperature-scale divisions of 2°F (1°C) spaced not lets than 0.040 of an inch apart are permitted when the ink line is thin enough to be easily distinguished from the printed line.
Temperature Accuracy.—Within 2°F (1°C) plus or minus, above 110°F (44°C).
Pen-Arm Setting Device.—Easily accessible; simple to adjust.
Pen and Chart Paper.—Designed to mark a line not over 0.025 of an inch wide; easy to maintain.
Temperature Sensor.—Protected against damage at 212°F (100°C).
Stem Fitting. —Pressure-tight seat against inside wall of pipe; no threads exposed to solution.
Chart Speed.—Circular charts shall make one revolution in not more than 24 hours. Strip charts shall not move less than 1 inch per hour. More than one record of the cleaning operation shall not overlap on the same section of the chart for either circular- or strip-type charts.
INDICATING THERMOMETERS USED IN REFRIGERATED ROOMS
Indicating thermometers used in refrigerated rooms where milk, milk products and whey are stored shall meet the following specifications:
Scale Range.—Shall have a span not less than 50 Fahrenheit degrees (28 Celsius degrees) including normal storage temperatures plus and minus 5°F (3°C) with extensions of scale on either side permitted, graduated in not more than 2°F (1°C) divisions.
Temperature Scale Divisions. —Spaced not less than 0.0625 of an inch apart between 32°F and 55°F (0°C and 13°C).
Accuracy. —Within 2°F (1°C) plus or minus, throughout the specified scale range.
SPECIFICATIONS FOR RECORDING pH METER FOR USE ON AUTOMATED MECHANICAL CLEANING SYSTEMS FOR EVAPORATORS
Location. —pH sensor shall be located in the return line down-stream from processing equipment and all lines included in the cleaned-in-place circuit.
Case.—Moisture-proof under operating conditions.
Scale.—It shall have a range of pH value from 2 to 12 with extensions of scale on either side permissible graduated in time scale divisions of not more than 15 minutes. The chart is to be graduated in pH divisions of not more than 0.5 pH values and spaced not less than 0.0625 of an inch apart.
pH Accuracy.—Within 0.5 plus or minus pH values.
Pen-Arm Setting Device.—Easily accessible; simple to adjust.
Pen and Chart Paper.—Designed to mark a line not over 0.025 of an inch wide; easy to maintain.
pH Sensor.—Protected against damage at 180°F (83°C).
Chart Speed.—Circular charts shall make one revolution in not more than 24 hours. Strip charts shall not move slower than 1 inch per hour. More than one record of the cleaning operation shall not overlap on the same section of the chart for either circular- or strip-type charts.