CCLME.ORG - DIVISION 1. STATE FIRE MARSHAL

(continued)
(f) Permanent Expansion. Zero, total and permanent expansion readings shall be taken at the same water level. The rise of level of the water in the burette tube when the pressure is applied to the cylinder under test is liable to cause very considerable error, as it produces a change in pressure within the jacket which tends to expand the jacket and compress any air which may be trapped in it if not leveled. The head of the jacket and all connecting pipes to the burette should be designed with a continuous upward slope with an air vent at the highest point so that no air can remain trapped in the jacket when it is filled with water.
(g) Accuracy of Equipment.
The best way of checking the accuracy of the equipment is by the use of a calibrated cylinder. This cylinder must have been previously tested with an apparatus which is known to be correct so that its elastic expansion at the test pressure has been accurately determined. Each day before retesting this calibrated cylinder should be placed in the jacket and tested in order to verify the accuracy of the test equipment. If its expansion does not agree with the known value, the cause of the error should be determined and corrected before proceeding with the testing.
(h) Instructions for Use of Calibrated Cylinder. A calibrated cylinder is a cylinder which has been carefully selected and stretched permanently by means of hydraulic pressure higher than the maximum pressure for which it is to be used.
(i) Volumetric Property of Expansion.
After this is done the cylinder has the property of expanding the same volume for each pressure unit for which it has been calibrated and returning to its original volume when pressure is released. As long as the cylinder does not have a hydraulic pressure applied to it higher than its calibration, or does not change its wall thickness, due to rust or deterioration, it will maintain these properties.
(j) Measurement. It is to be considered as an instrument for measurement rather than just a cylinder.
(k) Chart.
A chart shall accompany the cylinder showing the volumetric expansion in cubic centimeters at the various pressures.
(l) Checking Gauge and Burette.
In order to check the gauge, burette and all connections to a cylinder testing outfit, the cylinder is put into the jacket in the usual way; hydraulic pressure is applied until the volumetric expansion shown in the burette is equal to the volumetric expansion as shown on the chart, for whatever pressure is desired to test the outfit. Example: If it is desired to a test a water jacket, gauge and equipment at 3,360 P.S.I. and the volumetric expansion for the cylinder at that pressure is shown on the chart as 157, the pressure should be applied until 157 cc. expansion is shown on the burette. If the gauge, burette and all other parts are accurate the pressure shown on the gauge should be 3,360 P.S.I. at this point. D.O.T. requires gauges and burettes to permit reading to accuracy of 1 percent.
(m) Checking Elastic Expansion.
In using a calibrated cylinder with an equipment that has not been tested before, it is well not to make a test at a pressure near the maximum range of the cylinder, for the reason that should a gauge read low, a higher pressure than was indicated would be applied to the cylinder and could change its calibration. It is well to check the elastic expansion as compared with the chart furnished with the cylinder; then check the pressure recorded with the expansion rather than to run the pressure up first and check the expansion last.
(n) Volume of Calibrated Cylinder.
When checking the accuracy of hydrostatic testing equipment, the calibrated cylinder should have a volume reasonably comparable to that of the cylinders to be tested.
(o) Instructions for Care of Calibrated Cylinder.
Do not use a calibrated cylinder as a capacitor cylinder to slow down pumping speed when cylinders are being tested or for any purpose other than calibrating or checking the accuracy of the test apparatus.
(p) Spud.
Leave water and the cylinder test spud in the cylinder between tests.
(q) Storing Calibrated Cylinder.
Do not store a calibrated cylinder outside, or in any location subject to freezing temperatures. Calibrated cylinders should be kept preferably near test apparatus so that the temperature of the water in the cylinder and test apparatus will remain approximately the same.
(r) Hammer Test.
An empty cylinder before recharging should be examined for physical damage and exterior corrosion, followed by hammer test. Those cylinders which have a dull or peculiar ring when lightly tapped with a suitable sized hammer, should be carefully examined and if necessary, valve removed and interior examined with suitable light and retested before charging.

s 609.3. Methods of Test.
(a) The four approved methods for conducting the water jacket volumetric expansion method of hydrostatic testing are:
(1) Leveling burette. Power driven pump. Pressure connection to cylinder outside water jacket.
(2) Rod displacement. Hand pressure pump. Pressure connection to cylinder outside water jacket.

(3) Leveling burette. Hand pressure pump. Pressure connection to cylinder outside water jacket.
(4) Leveling burette. Power driven pump. Pressure connection to cylinder inside water jacket.
(b) Test Pressure.
The required test pressure shall be 5/3 of the service pressure of the cylinder under test.

s 609.4. Water Jacket Leveling. Burette. Power Driven Pump. Pressure Connected to Cylinder Outside Water Jacket.
(a) General.
The water jacket leveling burette method of testing cylinders consists essentially of enclosing the cylinder in a water jacket and measuring the volume of water forced from the jacket upon application of pressure to the interior of the cylinder, and the volume remaining displaced upon release of the pressure. These volumes represent the total and permanent expansions of the cylinder, respectively. To measure them accurately, a movable burette calibrated in cubic centimeters is positioned to maintain the water level at a uniform height when taking readings.
(b) Procedure.
The procedure for this method of testing shall be as follows: (See Table No. 20B.)
(1) Remove valve from empty cylinder and fill with water.
(2) Holding cylinder in valving vise, screw connection (C) into neck threads.
(3) Place cover (O) over shoulder of cylinder and tighten wing nut (V).
(4) Insert cylinder in water jacket (B), clamp water jacket head (O) in place and open petcock (P).
(5) Join cylinder connection (C) to coupling (D) on pump line. (Up to this point, valves I, J, K, L, M, Q, and U should be kept closed.)
(6) Set zero of burette (T) at eyelevel adjustable reference point (Z).

(7) Open valve (L) and after water flows from petcock (P), close petcock.
(8) When water in burette (T) rises above zero point, close valve (L).
(9) Adjust water level in burette (T) to zero by draining through valve (K).
(10) Open valve (I) and close by-pass valve (Q). When cylinder pressure rises to three-fourths I.C.C. test pressure, close valve (I) and open by-pass valve (Q).
(11) Examine apparatus for leakage (dropping pressure, falling water level in burette, or beads of water at screw threads in cylinder neck indicate leakage).
(12) If no leaks occur, open valve (I), close by-pass valve (Q) and raise cylinder pressure to desired test pressure, closing valve (I) and opening by-pass valve (Q).
(13) Maintain test pressure for 30 seconds and as much longer as may be necessary to secure complete expansion of the cylinder.

(14) Read the total expansion in burette (T) with water level flush with eyelevel zero mark (Z).
(15) Release pressure through valve (J) and read the permanent expansion in burette (T) with water level flush with zero mark (Z).

s 609.5. Water Jacket Rod Displacement. Hand Pressure Pump. Pressure Connection to Cylinder Outside Water Jacket.
(a) General.
The water jacket rod displacement method of testing cylinders consists essentially of enclosing the cylinder, suspended in a jacket vessel provided with necessary connections and attachments, and measuring the volume of water forced from the jacket upon application of pressure to the interior of the cylinder, and the volume remaining displaced upon release of the pressure. These volumes represent the total and permanent expansions of the cylinder, respectively. To measure them accurately a displacement rod (II) and a graduated scale (T) are used. The rod is accurately and uniformly machined from a noncorrodable material such as brass, bronze, or stainless steel and the scale is so calibrated that the water displaced by the rod, per unit of length, in the tube (S), is read upon the scale in cubic centimeters. This operation is described in paragraphs (21) and (22) of the procedure following.
(b) Procedure.
The procedure for this method of testing shall be as follows: (See Table No. 20C.)
(1) Remove valve from empty cylinder.
(2) Fill cylinder completely with water.
(3) Place cylinder in the valving vise.
(4) Screw connection (C) into cylinder neck threads.
(5) Place cover (O) over shoulder of cylinder, as level as possible, being sure that gasket (X) makes a tight seat on the neck of the cylinder.
(6) Tighten wing nut (V), pulling the cover down on shoulder of cylinder as tightly as possible.
(7) Place cylinder and cover as a unit into the water jacket (B).
(8) Clamp water jacket head (O) in place and open petcock (P).
(9) See that gasket (X) makes an absolutely tight seat against the shoulder of cylinder. This may be observed through openings provided for this purpose in the cover.
(10)Connect cylinder to source of pressure byu connection union (D) to connection (C). (Up to this point valves I, J, K, L, M. R, and U should be kept closed.)
(11) Lower displacement rod (II) in the brass tube container (S) until the top of the rod coincides with the zero mark on the scale (T). (See position 1 on drawing.)

(12) Open valve (L) until water flows from petcock (P) and rises above the water level mark in the glass tube indicator (W).
(13) Close valve (L).
(14) Close petcock (P).
(15) Open valve (K) slightly, drawing off water in the tube containers until the water is exactly at water level mark then close valve. If water goes below water level mark on glass tube indicator, open petcock (P) and repeat operations (12), (13), (14), and (15).
(16) Open valve (M).
(17) Start clock mechanism of recording gauge (G).
(18) Open valve (I) and pump pressure to about three-fourths of final test pressure.
(19) Close valve (I) and immediately examine apparatus for leaks. (Look through opening above gasket for leaks in cover). Water receding slowly in glass tube indicator denotes leakage. If no leaks appear open valve (I) and pump cylinder pressure to final requirement.
(20) Close valve (I) immediately to retain this pressure. Test pressure must be applied and maintained for at least 30 seconds and as much longer as may be necessary to secure complete expansion of the cylinder. Observations of the water in the glass tube indicator will enable this to be determined as the water will cease to rise when expansion is complete if pressure is maintained.
(21) Raise displacement rod (H) until water in glass tube indicator recedes to the original water level mark (i.e., the same level as indicated in operation (15)).
Note: Sufficient time should be taken to allow the water adhering to the rod and tubes to run down and collect at the bottom.
(22) Record total expansion in cc. by reading the number of cc. on scale (T) that correspond to the level of the top of the rod (H). This reading should be written on recording gauge (G) chart.
(23) Lower displacement rod (H) until the top of the rod coincides with zero on scale (T).
(24) Open valve (J) and release pressure on cylinder to zero as noted on gauge (F).
(25) Raise displacement rod (II) until the water in the glass tube indicator recedes to the water level mark, the water level then being the same as it was when readings under operations (15) and (22) were taken.
(26) Record the permanent expansion by reading the number of cc. on scale (T) corresponding to the level of the top of rod (II). This reading should be written on recording gauge chart. (Observe same note as in operation (21).)
(27) The percent expansion is read from chart (N) or calculated and equals permanent expansion divided by total expansion.
(28) Record percent expansion on recording gauge chart.
(29) Determine elastic expansion by subtracting permanent expansion from total expansion and record figure on recording gauge chart between that for permanent expansion and the percent expansion.

(30) If the percent expansion as read from chart (N) exceeds 10 percent the cylinder has failed to pass the test.
(31) If the elastic expansion indicates that the cylinder is thin walled it should be scrapped.
Note: (1) Use of recording gauge (G) is optional. If used, the chart should be kept as a permanent record and it is suggested that total expansion, permanent expansion, percent expansion and elastic expansion (as indicated in operations (22), (26), (28), and (29)) be noted on the chart. If recording gauge is to used, a permanent record of these factors should be kept elsewhere.
(2) All piping should be sloped upward to avoid air pockets. Use of pipe fittings should be minimized. They should not be used on horizontal lines, if possible.

s 609.6. Water Jacket Leveling Burette. Hand Pressure Pump. Pressure Connection to Cylinder Outside Water Jacket.
(a) General.
The water jacket leveling burette method of testing cylinders consists essentially of enclosing the cylinder, suspended in a jacket vessel provided with necessary connections and attachments, and measuring the volume of water forced from the jacket upon application of pressure to the interior of the cylinder, and the volume remaining displaced upon release of the pressure. These volumes represent the total and permanent expansions of the cylinder, respectively. To measure them accurately, a burette (T) and a flexible rubber hose (Y) are used. The burette will read the expansion directly in cubic centimeters when operated according to the procedures described in the following subparagraphs (21) and (22).
(b) Procedure.
The procedure for this method of testing shall be as follows: (See Table No. 20D.)
(1) Remove valve from empty cylinder.
(2) Fill cylinder completely with water.
(3) Place cylinder in the valving vise.
(4) Screw connection (C) into cylinder neck threads.
(5) Place cover (0) over shoulder of cylinder, as level as possible, being sure that gasket (X ) makes a tight seat on the neck of the cylinder.

(6 Tighten wing nut (V), pulling the cover down on shoulder of cylinder. This may be observed through openings provided for this purpose in the cover.
(7) Place cylinder and cover as a unit into the water jacket (B).
(8) Clamp water jacket head (O) in place and open petcock (P).
(9) See that gasket (X) makes an absolutely tight seat against shoulder of cylinder. This may be observed through openings provided for this purpose in the cover.
(10) Connect cylinder to source of pressure by connecting union (D) to connection (C). (Up to this point valves I, J, K, L, M. R, and U should be kept closed).
(11) Raise burette (T) until the zero of the scale coincides with a fixed water level mark (Z) adjacent to the scale and at the approximate eyelevel of the operator.
(12) Open valve (L) until water flows from petcock (P) and rises above the water level marker (Z) adjacent to the burette (T).

(13) Close valve (L).
(14) Close petcock (P).
(15) Open valve (K) slightly, drawing off water in the tube containers until the water is exactly at water level mark (Z) then close valve. (See position 1.) If water goes below water level mark, open petcock (P) and repeat operations (12), (13), (14), and (15).
(16) Open valve (M).
(17) Start clock mechanism of recording gauge (G ).
(18) Open valve (I) and pump pressure in cylinder to about three-fourths of final test pressure.
(19) Close valve (I) and immediately examine apparatus for leaks. (Look through opening above gasket for leaks in cover.) Water receding slowly in glass tube indicator denotes leakage. If no leaks appear open valve (I) and pump cylinder pressure to final requirement.

(20) Close valve (I) immediately to retain this pressure. Test pressure must be applied and maintained for at least 30 seconds and as much longer as may be necessary to secure complete expansion of the cylinder. Observations of the water in the glass burette will enable this to be determined as the water will cease to rise when expansion is complete if pressure is maintained.
(21) Lower burette (T) until water level in burette is flush with the original water level mark (Z).
Note: Sufficient time should be taken to allow the water adhering to the sides of the burette to run down and collect at the bottom.
(22) Record total expansion in cc. by reading the number of cc. of water in the burette (T). This reading should be written on recording gauge (G) chart.
(23) Open valve (J) and release pressure on cylinder to zero as noted on gauge (F).
(24) Raise burette until water level in burette is flush with the original water level mark (Z).

(25) Record the permanent expansion by reading the number of cc. of water in the burette. This reading should be written on recording gauge chart. (Observe same note as in operation (21).)
(26) The percent expansion is read from chart (N) or calculated and equals permanent expansion divided by total expansion.
(27) Record percent expansion on recording gauge chart.
(28) Determine elastic expansion by subtracting permanent expansion from total expansion and record figure on recording gauge chart between that for permanent expansion and the percent expansion.
(29) If the percent expansion as read from chart (N) exceeds 10 percent the cylinder has failed to pass the test.
(30) If the elastic expansion indicates that the cylinder is thin walled it should be scrapped.
Note: (1) Use of recording gauge (G) is optional. If used, the chart should be kept as a permanent record and it is suggested that total expansion, permanent expansion, percent expansion and elastic expansion (as indicated in operations (22), (25), (27), and (28)), be noted on the chart. If recording gauge is not used, a permanent record of these factors should be kept elsewhere.
(2) All piping should be sloped upward to avoid air pockets. Use of pipe fittings should be minimized. they should not be used on horizontal lines, if possible.

s 609.7. Water Jacket Leveling Burette. Power Driven Pump. Pressure Connection to Cylinder Inside Water Jacket.
(a) General.
The water jacket leveling burette method of testing cylinder in a water jacket and measuring the volume of water forced from the jacket upon application of pressure to the interior of the cylinder, and the volume remaining displaced upon release of the pressure. These volumes represent the total and permanent expansions of the cylinder, respectively. To measure them accurately, a moveable burette calibrated in cubic centimeters is positioned to maintain the water level at a uniform height when taking readings.
(b) Procedure.
The procedure for this method of testing shall be as follows: (See Table No. 20E.)
(1) Select the proper size burette for the cylinder to be tested and place in burette holder. Adjust rubber connection tight so it will not leak.
(2) With burette i position (1) set zero adjuster (H) with zero burette.
(3) Select test nipple (Z) to fit valve inlet connection thread of cylinder and screw into the jacket head with pipe wrench; be sure it is tight.
(4) Fill the cylinder to be tested with water. Clamp cylinder in vise and screw head and test nipple into the cylinder thread tight, using jacket head as wrench.
(5) Place cylinder in jacket by hoist and clamp head tight.

(6) Open valve (A) until water comes out of jet cock (B). Close (B). Fill hose and burette to zero or above. Close (A).
(7) Adjust water level in burette to zero by opening valve (C) with burette in position (1), with valves (E) and (J) open, (D) closed.
(8) Check for leaks. If water falls below zero in burette, jacket or piping is leaking. If water rises in burette, valve (A) is leaking.
(9) Close valves (E) and (J).
(10) Open valve (D) and pump to approximately 75 percent of test pressure (not over 90 percent). Close valve (D) and open valve (J). Check for leaks indicated by drop in pressure on gauge. Pressure leaks inside of jacket are indicated by water rising in burette.
(11) If free of leaks, close valve (J), open valve (D) and pump to desired test pressure. Close valve (D);open valve (J).
(12) Lower burette to position (2) with water in burette level with zero mark on zero adjuster (H). Hold for 30 seconds or until water stops rising in burette.
(13) Take total expansion reading in cc. and record.
(14) Release pressure on cylinder by opening valve (E).
(15) Raise burette to position (3) with water in burette level with zero mark on zero adjuster (H).
(16) Take permanent expansion reading in cc. and record.
(17) Calculate percent permanent expansion by dividing permanent expansion by total expansion and record. If over 10% cylinder fails under I.C.C. regulations.
(18) Example: Total expansion: 166 cc.;
% permanent expansion, 3.0/166.0 = 1.8%
166.0 Elastic expansion is equal to total expansion minus permanent expansion (166 cc. -3.0 cc. = 163 cc.).

(19) If elastic expansion indicates that cylinder is thin walled it should be scrapped.
Note: (1) All readings of the water in the burette must be taken with the water at the same level when in position (1), (2), and (3) to eliminate errors due to compression of entrapped air in jacket if any is present. Water in the cylinder, jacket, hose and burette should be at approximately the same temperature during test to eliminate errors in burette readings caused by expansion or contraction. When jacket is installed some distance from the burette leveler, and pipe (F) is used, install pipe (F) sloping upward and free from pockets which will entrap air; bends are preferable to pipe fittings. Flexible hose (G) should be heavy-wall hose, and installed so that the bending action when placed in positions (1), (2), and (3) will not change the interior volume. Install so that it will operate on long, easy curve. It is necessary to wash out jacket occasionally. Keep it free of dirt and organic matter. Valve (J) is to relieve pressure on the pump when valve (D) is closed. It is obvious that valves (D) and (J) cannot both be left closed and pump running. By releasing the pressure through valve (J), pump can be left running continuously when testing cylinders if desired. Relief valve (K) is only intended to relieve pressure on pump if valve (J) is left closed, when valve (D) is closed. It is not intended to operate continuously. Keep long full threads of test nipple, in jacket head, in good condition. Nipple can be cut off and rethreaded when worn.
Table No. 20B

Table No. 20C

Table No. 20D

TABULAR OR GRAPHIC MATERIAL SET FORTH AT THIS POINT IS NOT DISPLAYABLE
Table No. 20E

s 610. Direct Expansion Method.
This method may be used when equipment and operation is approved by the Bureau of Explosives. With this method, the interior volumetric expansion is determined, whereas the water jacket method determines the exterior volumetric expansion.
(a) Inspection of Cylinders.
(1) Before cylinders are retested, valves should be removed. An internal inspection shall be made with a suitable light. Scale and sludge deposits shall be removed.

(2) An exterior inspection shall be made for evidence of corrosion, dents, arc or torch burns and physical deformation.
(3) Cylinders which are dented, arc or torch burnt, or physically damaged, shall be condemned. Cylinders shall be condemned if the loss of metal thickness either by localized pitting or large area corrosion exceeds .005 inches for cold drawn cylinders or 1/32 inch for hot forged cylinders.
(b) Requirements and Preparation for Testing.
For the direct expansion method, testing requirements shall be as follows:
(1) The apparatus must be so arranged that all air can be eliminated from the apparatus and cylinder under test.
(2) When size, location or form of cylinder such as concave head and bottom make it difficult to vent all air, equipment for removing air and testing for air must be provided. The methods and apparatus applicable to all conditions are too varied and exacting to be included in this Code. Properly trained personnel should be employed.

(3) A dead weight testing apparatus must be used to verify the accuracy of pressure gauges. A master gauge checked by a dead weight tester at frequent intervals would be an acceptable substitute, though less desirable.
(4) The pressure gauges must agree with a dead weight testing apparatus to within 1/2 percent to test pressure. Gauges must have zero stop pin removed or replaced 1/2 inch below zero, and a true zero marked on the dial.
(5) An accurate scale to determine weight of water in cylinder.
(6) An accurate thermometer to determine the temperature of water in the cylinder.
(7) An accurate and authoritative chart of the compressibility of water at temperature and pressure of water in cylinder under test. (Suitable liquid such as kerosene may be used in place of water with proper precautions and proper compressibility chart for liquid used).
(8) A reservoir graduated in cc. and accurate to 1 percent of reading, arranged so that water required to pressurize the filled cylinder, and water expelled from cylinder when depressurized, can be accurately determined.
(9) Water in reservoir pump and connections must be the same temperature as water in cylinder.
(10) Pressure valves, piping and connections to gauges and cylinder must be heavy construction, short as possible and of as small volume as practical, and must be absolutely tight and free of leaks while cylinder is under test. (Elastic expansion and compressibility of water in piping to cylinder under pressure, is an error in the expansion of the cylinder under test and should be determined for various test conditions.)
(11) Any internal pressure applied previous to the test pressure shall not exceed 90 percent of test pressure. If due to failure of the test apparatus, the test pressure cannot be maintained, the test may be repeated at a pressure increased by 10 percent, or 100 P.S.I., whichever is the lower value. Test pressure must be maintained for at least 30 seconds and as much longer as may be necessary to secure complete expansion of the cylinder.
(c) How to Use Results of Tests.
The tests will determine the amount of water in cc. forced into the filled cylinder to pressurize the cylinder to desired test pressure; the amount of water in cc. expelled from the cylinder when cylinder is depressurized. With the weight and temperature of water in cylinder known, the water volume change due to the compressibility of the water can be calculated and the total and permanent expansion determined. The total expansion minus the permanent expansion is the elastic expansion and can be used for wall thickness determinations.
(d) Compressibility of Water.
C = FWP
C = Volume of water forced into cylinder due to compressibility of water in cc.
F = Compressibility factor from Bureau of Explosives curves.
W = Weight of water in cylinder at test pressure, pounds.
P = Test pressure, P.S.I.

1 pound water equals 454.5 cc.
1 cubic inch water equals 16.387 cc.
1 pound water equals 27.737 cubic inches.
EXAMPLES:

Test pressure ............................................... 3360 P.S.I.
Weight of water in cylinder zero pressure ................... 251 pounds
Temperature of water ........................................ 60<> F.
Water forced into cylinder to raise pressure to 3360 P.S.I... 1745 cc.
Weight of water added to cylinder to pressurize 1745 / 454.5
equals .................................................... 3.8 pounds
Total weight of water in cylinder at 3360 P.S.I. 251 + 3.8
equals .................................................... 254.8 pounds
Water expelled from cylinder to depressurize ................ 1698 cc.
Permanent expansion 1745 cc. - 1698 cc. equals .............. 47 cc.
Compressibility factor for water at 3360 P.S.I.
60<> F............................................ .001425
Volume of water forced into cylinder due to compressibility
of water in cylinder at 3360 P.S.I. and 60<> F.
cc. = .001425 x 254.8 x 3360 equals ....................... 1219.98 cc.
Total expansion 1745 - 1219.98 equals ....................... 525 cc.
Percent permanent expansion 47 / 525 equals ................. 8.95%
Elastic expansion 525 - 47 equals ........................... 478 cc.

Test pressure ............................................... 500 P.S.I.
Weight of water in cylinder zero pressure ................... 1657 pounds
Temperature of water ........................................ 73<> F.
Water forced into cylinder to raise pressure to 500 P.S.I.... 2736 cc.
Weight of water added to cylinder to pressurize 2736 cc. /
454.5 equals .............................................. 6 pounds
Total weight of water in cylinder at 500 P.S.I. 1657 + 6
equals .................................................... 1663 pounds
Water expelled from cylinder to depressurize ................ 2667.5 cc.
Permanent expansion 2736 - 2667.5 ........................... 68.547 cc.
Compressibility factor for water at 500 P.S.I. 73<>
F.......................................................... .001439
Volume of water forced into cylinder due to compressibility
of water in cylinder at 500 P.S.I. and 73<> F.
cc. = .001439 x 1663 x 500 ................................ 1196.5 cc.
Total expansion 2736 - 1196.5 ............................... 1539.5 cc.
Percent permanent expansion 68.5 / 1539.5 ................... 4.4%
Elastic expansion 1539.5 - 68.5 ............................. 1471 cc.

Note: The expansion of the pipe and fittings and the compressibility of the water in the portion of the pipe between valve (F degrees) and valve (D) and the cylinder (H) has been considered as zero. (See Table 20 F.)
(e) Elastic Expansion.
The elastic expansion as determined by the retest of a cylinder by the direct expansion method can be used for calculating average wall in the same way as calculated under the water-jacket method. The direct expansion method determines interior volumetric expansion whereas the water-jacket method determines exterior volumetric expansion.
(f) Wall Thickness.
Cylinder owners using the direct expansion method of testing should establish their own basis for determining average wall thickness by elastic expansion. The methods and calculations applicable to all conditions are too varied and too exacting to be covered in this code. Properly trained personnel should be employed.
(g) Condemned Cylinders.
A cylinder must be condemned if it leaks, or fails to pass the test requirements prescribed by the D.O.T. regulations.
(h) Exceeding Safe Permissible Stress.
Cylinders should be condemned when the wall stress at service pressure exceeds a safe permissible stress in the cylinder.
(i) Basis of Recommendations.
A cylinder can be tested by this method for total, permanent and elastic expansion. Care must be exercised to make certain that all parts of the equipment are functioning properly, that cylinder and equipment is free of all air. Temperature measurements and calculations for water compressibility, the measurements of water used to pressurize and depressurize the cylinder must be accurately determined. It is exceedingly important that no leaks in the high or low pressure parts of the apparatus occur which will cause errors in the calculations which must be carefully made.
(j) Hammer Test.
An empty cylinder before recharging should be examined for physical damage and exterior corrosion, followed by hammer test. Those cylinders which have a dull or peculiar ring, when lightly tapped with a suitably sized hammer, should be carefully examined and if necessary, valves removed and interior examined with suitable light and retested before charging.
(k) Test Pressure.
The required test pressure shall be 5/3 of the service pressure of the cylinder under test.
(l) Pressure.
The procedure for this method of testing shall be as follows: (See Table No. 20 G.)
(1) All valves closed, reservoir (N) filled with water.
(2) Weigh cylinder (empty).

(3) Fill cylinder with water, from reservoir (N) or from other source, water must be at the same temperature as cylinder and room.
(4) Weigh cylinder (filled).
(5) Measure temperature of water in cylinder, record temperature in degrees Fahrenheit.
(6) Determine weight of water in cylinder by subtracting weight of empty cylinder from weight of filled cylinder, call it W>1 in pounds and record.
(7) Screw test stem and valve (G) into cylinder (tight).
(8) Open valve (A).
(9) Open valve (C) and fill reservoir (J) half full of water.
(10) Close valve (C).
(11) Open valve (B) until all air is removed, close (B).

(12) Connect cylinder to apparatus with pressure connections (O).
(13) Open valves (G) and (D).
(14) Start pump and fill pump, piping and high pressure reservoir (L) from reservoir (N). When water free of air comes out of overflow pipe of top of cylinder, close (G).
(15) Open valve (F) when water free of air rises in reservoir (J), close (F).
(16) Open valve (E), when water free of air rises in reservoir (J), close (E). Allow pressure to build up not over 90 percent of test pressure.
(17) Open valve (G) to release pressure and purge all air out of top of cylinder and test stem.
(18) Stop pump and close valve (G).
(19) Repeat if necessary to expel all air from top of cylinder and test stem.

(20) When operating new equipment fir the first time break gauge connection and purge all air from pipe connecting gauge to equipment.
(21) Close valve (D).
(22) Close valve (A).
(23) Open valve (C).
(24) Open valve (E).
(25) Start pump and circulate water from reservoir (J) through pump, reservoir (L), and valve (E), back to (J).
(26) Stop pump.
(27) Close valve (E).
(28) Fill reservoir (J), and adjust water level to zero with valves (A) and (B).

(29) Close valves (A) and (B) with water at zero mark. Cylinder and system is now full of water free of air and ready for test, valve (C) open and all other valves closed.
(30) Open valve (D), start pump and raise pressure to approximately 75 percent of test pressure, not over 90 percent. Stop pump and check for leaks.
(31) If free of leaks start pump and pressurize cylinder to test pressure.
(32) Close valve (D).
(33) Open valve (E) and stop pump, water compressed in pump and system will return to reservoir (J). Test pressure will be retained in cylinder. Hold pressure in cylinder for 30 seconds, or as much longer as necessary to assure complete expansion of cylinder. If pressure gauge shows loss of pressure, pressure recessions must be made up until cylinder stops expanding.
(34) When cylinder has completely expanded take reading in cc. of water level in reservoir (J), record and call it (X). This represents total water added to cylinder to pressurize to test pressure and is equal to the total expansion of the cylinder plus the volume added to take care of compressibility of the water in the cylinder at test pressure.
(35) When cylinder has completely expanded take reading in cc. of water level in reservoir (J), record and call it (X). This represents total water added to cylinder to pressurize to test pressure and is equal to the total expansion of the cylinder plus the volume added to take care of compressibility of the water in the cylinder at test pressure.
(36) Depressurize the cylinder by opening valve (F), water will be returned to reservoir (J).
(37) Take reading in cc. of water level in reservoir (J) and record. Call it (P.E.). This represents the permanent expansion of the cylinder.
(38) Determine the weight of water added to pressurize the cylinder by dividing cc. recorded (X) in 34 by 454.5 the number of cc. in one pound of water. Call it W 2.
(39) Determine total weight of water in cylinder at test pressure by adding W 1 6, to W 2 37. Call it W and record.

(40) Determine compressibility factor from compressibility curves for test pressure and temperature recorded in 5.
(41) Calculate the volume of water added to take care of compressibility of water in cylinder at test pressure by formula:
C = FWP
C = Volume of water forced into cylinder due to compressibility of water in cc.
F = Compressibility factor from curve for test temperature and pressure.
W = Weight of water in cylinder at test pressure, determined 38.
P = Test pressure P.S.I.
(42) Determine total expansion of the cylinder by subtracting cc. as determined in (40) form (X) as determined in (34). Call it (T.E.) and record.
(43) Calculate percent permanent expansion by dividing permanent expansion (P.E.) found in (36) by total expansion (T.E.) found in (42), and record. If over 10 percent cylinder fails under D.O.T. regulations and specifications.
(44) Elastic expansion equals total expansion (T.E.) (41) minus permanent expansion (P.E.) (36). T.E. - P.E. = E.E.
(45) Record all readings and calculations for record.
TABLE NO. 20F

TABLE NO. 20G

s 611. Pressure Recession Method.

s 612. Proof Pressure Method.
(a) This method may be used when D.O.T. specifications and regulations do not require the determination of total and permanent volumetric expansion of a cylinder.
(b) Inspection of Cylinders.
(1) Before cylinders are retested valves should be removed. An internal inspection shall be made with a suitable light. Scale and sludge deposits shall be removed.

(2) An exterior inspection shall be made for evidence of corrosion, dents, arc or torch burns, and physical damage.
(3) Cylinders which are dented, arc or torch burnt, or physically damaged shall be condemned. Cylinders shall be condemned if the loss of metal thickness either by localized pitting or large area corrosion exceeds .005 inches for cold drawn cylinders or 1/32 inch for hot forged cylinders.
(c) Requirements and Preparation for Testing.
For the proof pressure method, testing requirements shall be as follows:
(1) The apparatus must be so arranged that careful inspection, including the bottom, can be made while cylinder is under test pressure.
(2) A dead weight testing apparatus must be used to verify the accuracy of pressure gauge. A master gauge checked by a dead weight tester at frequent intervals, would be an acceptable substitute though less desirable.
(3) The pressure gauge must agree with a dead weight testing apparatus within one-half percent at the test pressure. Gauges must have zero stop pin removed or placed one-half inch below zero and a true zero marked on the dial.
(4) Test pressure must be maintained for at least 30 seconds and as much longer as may be necessary.
(5) Cylinders may be manifolded and tested in groups.
(6) The testing medium may be water or any suitable liquid such as kerosene.
(7) Any suitable pressure source may be used. If air or gas is used proper precautions must be made to protect personnel.
(d) How to Use Results of Tests.
A cylinder must be condemned if it leaks, ruptures, or shows evidence of bad dents, corroded areas or other conditions that indicate possible weakness which would render the cylinder unfit for service.
(e) Schematic Diagrams and Instructions for Operating.
Design and details of equipment to suit individual requirements can be adopted by the individual but should follow these recommendations for accurate testing and safety.
The proof pressure method may be used instead of the volumetric expansion method for retesting cylinders if applied within: (a) 10 years after cylinder was tested by the volumetric expansion method, or (b) five years after cylinder was tested by the proof pressure method. The test consists essentially of applying an internal hydrostatic pressure at least two times the cylinder service pressure and holding the pressure for a period of at least 30 seconds. If the cylinder does not leak or does not rupture it passes the test. However, the cylinder cannot be returned to service until it has been carefully examined externally and no evidence found of bad dents, corroded areas, or other conditions which would indicate weakness and render the cylinder unfit for service.
Two types of pressure source may be used; one, a hydraulic pump discharging directly into the cylinder to be retested, and two, a source of high pressure gas (air, nitrogen or carbon dioxide) applied to the top of a liquid pressure reservoir containing the liquid pressurizing medium which is connected to the cylinder to be retested.
(f) Hammer Test.
An empty cylinder before recharging should be examined for physical damage and exterior corrosion, followed by hammer test. Those cylinders which have a dull or peculiar ring, when lightly tapped with a suitably sized hammer, should be carefully examined and if necessary, valves removed and interior examined with suitable light and tested before charging.
(g) Test Pressure.
The required test pressure shall be 5/3 of the service pressure of the cylinder under test.
(h) Procedure.
The procedure for this method of testing shall be as follows: (See Table 20L.)
(1) Fill cylinder (A) full of liquid which may be water or some other fluid such as kerosene.

(2) Close valve (G) to drain.
(3) Open valve (H).
(4) Free system of gas or air by purging through connector (B).
(5) Make connector (B) tight to liquid full cylinder (A).
(6) Operate pump or apply pressure from suitable source until required test pressure is indicated on gauge (C). Close valve (H).
(7) Test pressure must be maintained for at least 30 seconds.
(8) The cylinder exterior shall be carefully inspected while the test pressure is maintained on the cylinder. Special attention should be given to inspection of cylinder bottoms. If valve (G) is closed and the pressure on the gauge falls it is an indication of a leak, deformation of cylinder or change in temperature of testing liquid.
TABLE NO. 20L

(9) Release the pressure by opening valve (G) to the drain or by returning the liquid to reservoir by opening valve (H).
(10) Remove connector (B) from cylinder (A).
(11) Drain cylinder (A).
(12) Exterior inspection, including the bottom, should be carefully made for corrosion, dents, arc or torch burns, and physical deformation. Seriously corroded cylinders should be condemned. Cylinders dented, arc or torch burnt, or physically damaged, to cause serious concentrated stresses, should be condemned.
(13) If cylinder has successfully passed hydrostatic test and external inspection it shall be stamped with date of test. After this date the letter "S" must be added to indicate that the cylinder was retested by a "Special Modified" hydrostatic test.
(14) A permanent record must be made of all cylinders tested indicating the type, registered symbol, and serial number of the cylinder together with date of test, operator, test pressure and test inspection data.

s 613. Test Record.
Each extinguisher which favorably passes the hydrostatic test shall be fitted with a record tag of metal or equally durable material or shall have stamped upon the extinguisher shell the following information:
(1) Date of test.
(2) License registration number of the testing concern.
Exception: An identifying symbol or mark may be used in lieu of the registration number of the testing concern. Such symbol or mark shall be submitted to the State Fire Marshal, shall be approved by him, and shall be recorded in the files of the State Fire Marshal.
A symbol or mark shall be approved for one concern only, and no other concern shall use such symbol or mark. Approval of the assignment of such symbol or mark shall be based upon the date of submission. The earliest postal date of any submission shall take precedence.

s 614. General.

Note: Authority cited: Section 13160, Health and Safety Code. Reference: Sections 13190.1, 13190.2 and 13190.3, Health and Safety Code.

s 614.1. Size and Color.

Note: Authority cited: Section 13160, Health and Safety Code. Reference: Sections 13190.1, 13190.2 and 13190.3, Health and Safety Code.

s 614.2. Attaching Tag.
(a) One service tag shall be attached to each portable fire extinguisher in such a position as to be conveniently inspected. The service tag may be attached to the extinguisher by means of wire, string, or plastic ties or by the use of a self adhesive tag approved by the State Fire Marshal.
(b) Internal maintenance tags shall be placed within the top three inch (3 ") portion of the siphon tube below the valve assembly. Internal maintenance tag shall be placed on siphon tube in the following manner:

(1) Place one end of adhesive side to siphon tube.
(2) Bring remainder of tag around tube and overlap tag.
(3) Completed tag should be at a 90 angle to siphon tube with the tag overlapping itself.
(4) Old tag should be removed at time of new service.

Note: Authority cited: Section 13160, Health and Safety Code. Reference: Sections 13190.1, 13190.2 and 13190.3, Health and Safety Code.

s 614.3. Tag Information.
Note: See Sections 13164 and 13170, Health and Safety Code.

s 614.4. Format.
Subject to the use requirements of section 597.3, the following format shall be used for all service tags.
Exceptions:
(1) Service tags for use by persons not a licensee or employed by a licensed concern shall not bear the seal of registration.
(2) Service tags may be printed or otherwise established for any number of years not in excess of 5 years.
(3) Service tags conforming to the provisions of the regulations adopted by the State Fire Marshal prior to the effective date of these revisions, may be attached to serviced extinguishers until not later than January 1, 1977, to allow for the use of existing tags. Every tag attached to an extinguisher after this date shall be an approved service tag conforming to section 614.4.
Note: Various combinations may be marked or punched for any one service. Factory charged extinguishers shall have the space "New Ext." marked or punched. New extinguishers charged by a licensed concern shall have the space "charged" marked or punched and may in addition have the space "New Ext." marked or punched.
It is possible to have spaces "Recharged" (as defined in these regulations) "Inspected" (weighing of cylinder) both marked or punched as a result of one service.

s 614.5. New Tag.

s 614.6. Tag Wording.

s 614.7. Removal.

s 614.8. Restrictive Use.

s 615. Enclosure.
This type of enclosure is for use in climates where temperatures below zero Fahrenheit are encountered; where the temperature does not fall below zero Fahrenheit, enclosure may be constructed of 7/8 inch material without the double wall.
(a) The inside dimensions of enclosure shall be as small as practical, but not to interfere with the quick removal of the extinguisher.
(b) Walls shall be tightly constructed of wood, not less than 1/2 inch thick; the inside of the cabinet to be lined with 1/2 inch wallboard, or its equivalent, so arranged as to leave a 1/2 inch air space between the inside and outside walls.
(c) Door shall be of double construction, closing into a rabbet, hinged and held closed with a spring latch.
(d) Near the bottom of the door, and at point opposite to the incandescent lamp, the door shall be double glazed (size of glass not larger than 4 by 7 inches), with double strength glass, and airspace of 1/2 inch maintained between the glazing. The outer glass should be clear red (or blue) so that the lamp used for heating purposes may be readily observed, and also the location of the extinguisher indicated.
(e) At a point about four inches up from the bottom, there shall be provided four 1/4 inch iron rods set into the sides of the cabinet, and arranged to carry the extinguisher.
(f) Under these rods, on the back of the cabinet, shall be mounted a three-inch conduit box and receptacle. All wiring shall be done in accordance with the National Electrical Code, by means of flexible or rigid conduit, or approved reinforced portable cord.
(g) An incandescent lamp of sufficient capacity (not less than 50 watts) to keep the temperature in cabinet above 40 degrees F., but to in excess of 90 degrees F., shall be continuously burned or thermostatically energized during cold weather.
(h) Electric heaters listed by Underwriters' Laboratories, Inc., may be used under the conditions specified.

s 616. Method Classification.
Under the present method of classification it is possible for units of the same size to have different classifications. For example, 15-pound carbon dioxide extinguishers may have a classification of 4-B:C, 6-B:C, or 8-B:C, according to the fire extinguishing potential of the individual units. Therefore, an exact conversion from the old method to new method of classification is not possible.

s 616.1. Use of Table (New).
Wherever fire extinguishers are found with the present classification on the label, this table should not be used. The classification is usable directly in the application of Article 11, "Placement of Portable Fire Extinguishers," of this part.

s 616.2. Old Classification (Conversion).
Wherever fire extinguishers are found with the old classification on the label, use this table for approximate conversion and use the resulting classification value in applying Article 11 of this part. For example, a 15-pound carbon dioxide extinguisher has the classification "B-1, C-1" on the label. From this table, it is found that the approximate classification under the present method is "4-B,C" ( -158). (continued)