Veriforce TG CCT 407OP. Training Guide

Transcription

1 Training Guide Directions: This training guide is to be used by a Veriforce Authorized Evaluator/Trainer and Trainee during on-thejob training (OJT) or prior to an evaluation as a resource. (S) Indicates a demonstration or skill task; (K) indicates a knowledge task. OJT Reminder: OJT is an active hands-on process. Practice should be as similar to the actual job task as possible. However, if the training is being provided on an actual job site while a covered task is actually being performed, the Evaluator either needs to be qualified on that covered task or be assisted by someone who is qualified on the covered task. The Evaluator should closely monitor the Trainee's practices to ensure safe and correct task performance. At no time should a non-qualified individual perform, or train for, a covered task unless directed and observed by a qualified individual. However, if the span of control for that particular covered task is 1:0 (requiring only qualified individuals to perform the covered task), the training must be simulated. Training is simulated by "walking through" the task and simulating all actual manipulations (valves, switches, tools, etc.) an individual would use during the performance of a covered task. Simulating includes the use of safety and administrative requirements as if the task were being performed live. Refer to the Veriforce Evaluator Training Program for more on how to conduct formal OJT. Disclaimer: This training resource is offered in good faith. Anyone choosing to utilize or rely on this training resource is doing so at their own discretion, risk and choice. Although every attempt has been made by Veriforce, LLC (the Company ) to ensure the correctness and suitability of this document and to correct any errors brought to the attention of the Company, the Company makes no representation or warranty regarding correctness or suitability (either directly or indirectly) of information referenced or implied within this training resource. In no event shall the Company be liable for any damages (including, but not limited to, special, incidental or consequential damages) whatsoever (including, but not limited to, death, personal injury, damage to person or property, loss of use, and/or loss of revenues), whether in an action of contract, negligence, or other action, arising out of or in any way associated with the use or misuse of this document. All critical information should be independently verified by the user and the user shall not rely on the contents provided herein without such independent verification. The subject matter included in this training has been compiled from a variety of sources and is subject to change without notice. The Company reserves the right to add, remove and alter information contained in this document without notice. The Company may provide links to other sites for your convenience; however, the Company takes no responsibility and makes no representation or warranty regarding the accuracy or currency of information contained within such sites. The Company does not endorse any information, goods, or services referred to within such sites, and the provision of links by the Company shall not be interpreted to be an endorsement of such information, goods or services. The content of this training resource is provided for personal use only, and all other use, copying or reproduction of this training or website or any part of it is prohibited. CCT: 407OP Perform Cathodic Protection Survey Page 1 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

2 Recommended Student Training or Resources: Recommended Student Training or Resources: DOT 49 CFR (e) DOT 49 CFR (a) DOT 49 CFR (e) DOT 49 CFR (d)(6) DOT 49 CFR (a) Perform Cathodic Protection Survey Cathodic protection (CP) systems are used to mitigate external corrosion on buried and submerged metallic structures, such as pipelines. Each pipeline that is under cathodic protection must be tested annually to ensure it is meeting protective criteria and providing protection from external corrosion. The Pipeline and Hazardous Materials Safety Administration (PHMSA) regulations 49 CFR (a) and 49 CFR (a) require each pipeline under CP to be tested at least once each calendar year, but with intervals not exceeding 15 months, to determine whether the level of CP meets the requirements for external corrosion control. In the pipeline industry, a cathodic protection (CP) survey (or electrical survey) is a technique that can determine whether a pipeline under CP is receiving adequate protection. This training will highlight the main aspects of performing a CP survey. It is not intended to substitute any technical or on-the-job training. For specific CP survey procedures, please refer to the applicable standard operating procedures. Knowledge Explain what is required prior to performing the task. Operator-Approved Procedures Before we cover performing the actual surveys, there is an important detail that needs to be addressed. You need to ensure that you follow any site-specific pipeline operator-approved procedures. These procedures can vary between pipeline operators and from site to site. Examples of these can include, but are not limited to: Format of survey results Cathodic protection voltage requirements Method of notification for affected landowners and/or foreign pipeline operators Knowledge Identify and describe the test equipment used to complete a cathodic protection survey. Performing cathodic protection surveys requires the appropriate equipment and materials. These can vary depending on the type of survey, type of measurements performed, field conditions, and applicable standard Page 2 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

3 operating procedures. Generally, CP surveys will require some or all of the following: Digital or analog high impedance voltmeter Reference cell Ammeter (direct or indirect) Current interrupter (as required) Data logger or other data recording device Voltmeter A voltmeter is an instrument used for measuring the potential difference, or voltage, between two points in an electrical or electronic circuit. There are two types of voltmeters: analog and digital. Analog Voltmeter Analog voltmeters use a needle and a calibrated scale to indicate values. These instruments consist of an internal magnet with a moving electric coil. As current passes through the coil, a needle that is attached to the coil moves across the scale of the voltmeter and produces a reading. Digital Voltmeter Digital voltmeters are electronic instruments that collect data and display an average value. The digital data is normally displayed on a liquid crystal display (or LCD). Some digital voltmeters are equipped with a variety of features, such as the auto-range feature, which allows for the measurement of different voltage values. High Impedance Voltmeters must be equipped with high impedance, or input resistance. When a meter is attached to a circuit, the meter becomes part of the circuit it is measuring. The meter itself changes the resistance of the circuit it is measuring, thus changing the reading. Input impedance represents the ability of the meter to measure a circuit parameter without affecting the reading. Therefore, a high impedance voltmeter is required in order to obtain accurate potential measurements. Most conventional meters on the market today have an internal impedance of 10 megohms suitable for all but the highest resistivity environments. Ammeter The measurement of AC or DC current flowing through a pipeline is a useful measurement in cathodic protection. Ammeters are instruments that measure either direct or alternating current in amperes. Just like voltmeters, ammeters tend to influence the amount of current in the circuits they're connected to. However, instead of having high internal resistance, as is the case with a voltmeter, the ideal ammeter would have zero internal resistance in order to obtain accurate readings. Ammeters can be connected either directly or indirectly to the circuit being measured. Direct Connection Page 3 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

4 In a direct connection, the ammeter is connected in series with the circuit being measured. Ammeters that are directly connected must have a low internal resistance in order to obtain accurate measurements. Indirect Connection In an indirect connection, the ammeter is not directly connected to the circuit. As a result, the ammeter does not add additional resistance, which increases the accuracy of the readings. In addition, this type of connection is preferred because it prevents the individual from coming in direct contact with the circuit. Indirect ammeters rely on the relationship between current flow in a conductor and the electromagnetic field that it generates. A common type of indirect ammeter is the clamp-on ammeter. Clamp-on meters have jaws which can be opened and then secured around the circuit wire. They make for quick and safe current measurements, especially on high-power industrial circuits Multimeters Multimeters have the capability of measuring multiple electrical values. At a minimum, most multimeters combine three distinct types of meters (voltmeter, ammeter, and ohmmeter) into a single device. As a result, multimeters are commonly used by field personnel when performing CP measurements. For simplification purposes, the term multimeter will be used in this course. Reference Cell A reference cell (also known as a reference electrode or half-cell) is an electrode which has a stable and wellknown electrode potential. Reference cells serve as the constant potential in structure-to-electrolyte measurements. Structure-to-electrolyte measurements, or potentials, will be discussed later in the course. Reference cells are available in transportable models as well as models manufactured for permanent burial or immersion. There are different types of reference cells, such as the zinc and calomel cells, but the ones most commonly used during CP surveys include the following: Copper-copper/sulfate (CuCuSO 4) Silver-silver/chloride (AgAgCl) Copper-Copper/Sulfate (CuCuSO 4) The CuCuSO 4 reference cell consists of a copper rod and a saturated copper sulfate solution housed inside of a plastic tube with a porous plug at one end. The plastic tube is partially clear in order to see the level of solution. The CuCuSO 4 reference cell is usually used for structures in soil or fresh water. Silver-Silver/Chloride (AgAgCl) For high chloride environments, such as seawater and marshlands, a AgAgCl reference cell is required. This cell consists of a silver rod housed in a manufactured seawater solution. Two major types of silver-silver/chloride cells are available: Seawater or open type Page 4 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

5 Saturated type Each type has its own application. It is important to note that the type of reference cell to use will be determined by the environment in which the cell is placed. For example, if a CuCuSO 4 reference cell is used in high chloride environments, such as sea water, it can suffer from chloride contamination, which may produce inaccurate readings. Current Interrupter When performing corrosion measurements on pipelines under CP, the ability to interrupt the CP current is important in order to adequately determine the level of protection. CP current can cause different readings when performing potential measurements due to IR drop, or voltage gradients. IR drop will be discussed in greater detail later in the course. Current interrupters are used to turn the CP current that is supplied to the structure ON and OFF. Measurements performed immediately after the CP current is interrupted are referred to as instant OFF potentials, while measurements performed with the CP system operating are ON potentials. Current interrupters can be installed in all DC power sources, such as rectifiers, that supply CP current to a pipeline. Some interrupters connect and interrupt on the AC power side. There are a variety of current interrupters available on the market. Portable current interrupters are usually compact and lightweight. Fixed interrupters are usually packaged with Remote Monitoring Units (RMUs). Most of these devices provide precision timing, and have the ability to coordinate their interruption with multiple interrupters. More advanced interrupters have the ability to utilize GPS technology to eliminate timing problems that are present when multiple interrupters are used. Recording Device During a CP survey, numerous measurements are often performed over a broad distance. To facilitate the recording and interpretation of such measurements, various recording devices can be used. One of the most common types of recording devices is the data logger. Data Logger Data loggers can store and collect data as well as perform different types of measurements (such as pipe-tosoil potentials). They can store thousands of data entries as well as text comments. These devices can also connect to computers to facilitate the interpretation of information. Skill Demonstrate how to perform a test equipment check to verify that the equipment functions within specified parameters. Inspection and Calibration - Multimeters Page 5 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

6 All equipment used in a cathodic protection survey should be inspected for damage and properly calibrated. Voltmeters, ammeters, and multimeters should be checked for operation and accuracy before and after their use. A measurement on a known source can be performed to confirm the accuracy of each meter. Regarding calibration, the meters should be calibrated and certified annually or as specified by the operator. Typically, this requires sending the meters back to the manufacturer or to a qualified third party calibration company. All meters should have a calibration sticker attached to them or documentation available stating the calibration specifics. Inspection and Calibration Reference Cells Reference cells should be inspected for damage and kept away from direct sunlight. They should be kept at least three-quarters full, with a well-saturated copper sulfate solution. There should always be a few extra sulfate crystals in the reference cell to ensure that the solution is saturated. Use only distilled water to refill the reference cell. Special consideration should be given to the porous plug of the reference cell. The porous plug should be in good condition and free of debris in order to achieve good contact with the electrolyte. Because the plug or tip is porous, contaminants in the soil can gradually move into the reference cell. A contaminated reference cell can produce inaccurate potentials. Because of this, reference cells should be checked and calibrated before each use. There are many different ways to calibrate a reference cell. A common way is to measure the potential difference to a standard or master reference cell. The master reference cell should not be used for any purpose other than calibration. To calibrate, simply place the porous plug of each reference cell end to end and measure the difference. You may need to place the cell tips in water to get a reading. Refer to the applicable standard operating procedures for specific reference cell calibration requirements. Skill Identify and demonstrate how to perform test point and AC potential surveys. One of the most common methods of testing the adequacy of CP is the annual test point survey. A test point survey is a series of CP measurements performed at predetermined test points. A test point is an individual, specific monitoring point in which a multimeter or other test equipment can be attached to obtain CP measurements. Test points are typically found within a test station; however, other pipeline components such as risers and valves can also serve as test points. Performing a Test Point Survey Actual test point survey procedures will vary due to a variety of factors (type of measurement, equipment, field conditions, etc.). Page 6 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

7 For specific test point survey requirements, refer to the applicable standard operating procedures. ON Potentials The following is a basic overview of how to perform a test point survey measuring ON potentials. Determine the location of the test points within the area to be surveyed. Set the multimeter to the DC volt scale. Connect the multimeter negative ( common or black) lead to the reference cell. Place the reference cell in direct contact with the soil and directly over the pipeline. Ensure the reference cell is placed in a vertical position (tip down). Ensure the cap is removed from the porous plug of the reference cell, and make sure the plug makes good contact with the ground. Ensure the soil where the reference cell is placed is moist. Add water if necessary. Note: Inaccurate readings may be obtained if the reference cell is placed on concrete or similar surfaces. Connect the multimeter positive (red) lead to the pipeline (via test point). Obtain and record the pipe-to-soil potential. Repeat this procedure at all test points in the area to be surveyed. ON/OFF Potentials The following is a basic overview of how to perform a test point survey measuring ON/OFF potentials. Determine the location of the test points within the area to be surveyed. Inspect the rectifier(s) within the area to be surveyed for proper operation, if qualified to do so. See CCT 408 Inspect Cathodic Protection Rectifier Online Training for more information. If not already equipped, install current interrupters at all rectifiers that will influence the survey. Follow the current interrupter s manufacturer instructions. Set the multimeter to the DC volt scale. Connect the multimeter negative ( common or black) lead to the reference cell. Place the reference cell in direct contact with the soil and directly over the pipeline. Ensure the reference cell is placed in a vertical position (tip down). Ensure the cap is removed from the porous plug of the reference cell, and make sure the plug makes good contact with the ground. Ensure the soil where the reference cell is placed is moist. Add water if necessary. Note: Inaccurate readings may be obtained if the reference cell is placed on concrete or similar surfaces. Connect the multimeter positive (red) lead to the pipeline (via test point). Obtain and record the ON potential (voltage potential with the protective current applied). Without moving the reference cell from the position in the previous step, obtain and record the instant OFF potential (voltage potential with protective current temporarily interrupted). Repeat this procedure at all test points in the area to be surveyed. AC Potential Surveys Depending on your pipeline operator, you may be required to conduct an AC potential survey at the same time corrosion structure-to-soil potentials are taken. An AC potential survey is a series of structure-to-electrolyte alternating current (AC) potential measurements. Page 7 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

8 AC potential surveys are usually conducted when pipelines run near high voltage electric transmission lines or when they parallel these lines. AC current is not normally considered a corrosion factor, but it can occur, thus the need for testing. The more likely issue is a safety concern as personnel may be subject to a shock hazard. Induced AC voltages can be developed through inductive coupling with the electric conductors and result in safety-related situations. Possible shock hazard situations should be recognized whenever corrosion personnel are performing tests on pipelines that are in the proximity of these electrical systems. It s important to recognize pipeline situations with exposure to high voltage electric transmission lines, such as pipelines with any common right-of-way with high voltage electric transmission lines, or pipelines located near electric system steel tower footings or buried electric ground wires. To reduce the risk of shock hazard, you should: Wear the standard safety equipment as required by your company and/or operator. Use electrically insulated test leads with insulated clip connectors. Avoid contacting the pipe structure with one hand and any grounded structure with the other hand. Avoid simultaneously contacting the pipe on both sides of an insulating flange or fitting in the pipeline. Take any other necessary precautions. Performing an AC Potential Survey An AC potential survey usually consists of two types of measurements: the structure-to-structure AC voltage and the structure-to-soil AC potential (both of which were covered earlier in the course). AC potentials can consist of taking a structure-to-soil and/or structure-to-structure AC potential. To measure a structure-to-soil AC potential, select the appropriate AC scale on the multimeter, and connect the positive lead to the structure and the negative lead to a CuCuSO 4 reference cell. To measure a structure-to-structure AC voltage (e.g. test station to fence), connect one lead to each of the structures. An important thing to consider when performing an AC potential survey is the structure-to-soil AC voltages. If such readings are found to be greater than 15 volts, you should contact your designated operator representative. Knowledge Identify and describe measurements that may be required at a given test point. Test Point Measurements There are certain measurements that may be required at a given test point. These types of measurements may include the following: Structure-to-electrolyte potential AC potential Current flow measurement on pipelines Galvanic anode output measurement Page 8 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

9 Structure-to-Electrolyte Potential A structure-to-electrolyte potential measures the potential of the structure in an electrolyte, such as soil or water, with respect to a standard reference electrode. There are different types of structure-to-electrolyte potentials. Some of the most common include: Pipe-to-soil Pipe-to-water Structure-to-soil Casing-to-soil Foreign line-to-soil Pipe-to-Soil potential A pipe-to-soil potential is perhaps the most frequently performed corrosion measurement. A pipe-to-soil potential is a structure-to-electrolyte potential that measures the potential of the pipe (or service riser, tracer wire, test station, or any other component where contact can be made to take a pipe-to-soil measurement) in an electrolyte such as soil or water, with respect to a standard reference electrode. Measurements are obtained by connecting a multimeter between the pipe and a reference cell that is in contact with the soil. The positive lead of the multimeter is placed in contact with the appropriate test point connection, while the negative lead is connected to the reference cell. The reference cell is placed in the soil directly over the pipeline. Once the potential is taken, the reading is analyzed and a determination is made as to whether or not the pipe is receiving adequate CP at that specific point. Pipe-to-Water Potential Pipe-to-water potentials are similar in nature to pipe-to-soil potentials; the difference is that the reference cell is placed in water rather than soil. For fresh water applications, a conventional CuCuSO 4 reference cell can be used. However, for high chloride environments, such as seawater, a AgAgCl reference cell is required. Note: If a pipe-to-water potential is conducted in seawater, refer to the applicable CP criteria for potentials which are performed with a AgAgCl reference cell. Structure-to-Soil Potential The structure-to-soil potential is often used to describe a pipe-to-soil potential since the term structure is often related to pipelines. However, structures are not limited to just pipelines. The term structure can refer to other buried or submerged structures, such as underground and aboveground storage tanks and pipeline casings. Casing-to-Soil Potential Casings are bare pipes that shield and protect a pipeline from physical damage and load stress that can exist at railroad or road crossings. Although helpful in protecting pipelines, casings can have a negative effect with regards to CP when they Page 9 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

10 come into contact, either directly or indirectly, with the pipe. Shorted Casing When the casing makes contact with the pipe, CP current can be lost, and the effectiveness of the CP system can be compromised. This condition is often referred to as a shorted casing. When testing for a shorted casing, a pipe-to-soil and a casing-to-soil potential are performed, and the difference between the two potentials is analyzed. Generally, if a difference of at least 100 millivolts is present then the casing is deemed to be properly isolated. If the difference is less than 100 millivolts, the casing may be shorted and further testing may be required. Foreign Line-to-Soil Potential Foreign line-to-soil potentials can help determine if interference problems exist. Interference can occur at areas where a pipeline crosses a foreign line(s). If any line at such crossing is under CP, stray current can develop and cause corrosion on one of the lines. Test stations are often strategically installed at foreign line crossings in order to facilitate foreign line-to-soil potentials. Pipe-to-soil readings are taken on the pipeline operator s line and compared to the readings taken on the foreign line. AC Potentials AC potentials are another type of measurement that may be required at a given test point. AC potential measurements are sometimes required at the same time corrosion structure-to-soil potentials are taken. They are usually conducted when pipelines run near or parallel to high voltage electric transmission lines, electric sub-stations, switching stations, generating stations, electrical steel tower footings, buried electrical ground wires, or any other buried metallic structures connected to the electrical ground system. Current Flow Measurements on Pipelines The measurement of current output is used to make sure sufficient current is being applied to the pipeline. Although other methods can be used, current flow measurements can be done by accessing an IR drop test station that spans along a known length of pipe. There are two types of IR drop test stations: 2-wire test points, which include 1 test wire from each end of a pipe span 4-wire test points, which include 2 test wires from each end of the span If a 2-wire test point is available, currents may be measured by determining the potential drop across the span, selecting the pipe resistance from tables and calculating the current using Ohm s law. 4-wire test points are best equipped for accurate measurements of pipeline current because each span can be calibrated accurately. This avoids errors in length of pipe span and resistance that may occur when 2-wire test points are used. Note: When making pipeline current measurements, noting the polarity of the instrument connections (which end of the span is (+) and which is (-)) is extremely important. This is necessary so that the direction of current flow is known. 2-wire and 4-wire test points are usually color coded in order to allow for the appropriate connections to be made. Check with the pipeline operator to review their color scheme. Page 10 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

11 Galvanic Anode Output Measurement Veriforce TG CCT 407OP Another type of measurement is the galvanic anode output measurement. Galvanic anodes are used to protect buried or submerged pipelines from corrosion. A galvanic anode will corrode in preference to the metallic structure that is cathodically protected. With time however, anodes will eventually corrode and ultimately fulfill their lifetime expectancy. As anodes approach the end of their useful life, their current output will diminish. For this reason, it is important to identify the anode s current output to determine its operating condition and more importantly, to make sure that sufficient current is being applied to the pipeline. There are two ways of performing an anode output measurement. The first method involves using an ammeter in series with the anode lead and pipeline lead. This method is mainly used for Galvanic Anode CP systems. For Impressed Current CP systems, the anode output is measured by connecting a voltmeter across a shunt at a distribution box. Knowledge Describe the use of interrupters. Inspection and Calibration Current interrupters (both portable and RMUs) should be examined for damage. If the device is damaged, do not attempt to repair it. Send the current interrupter back to the manufacturer/supplier to be repaired or replaced. Note: Only use calibrated equipment and reference the applicable standard operating procedures and manufacturer instructions when using and installing a current interrupter. Before use, check the current interrupter s battery supply. Note that some interrupters run off batteries and some from AC. Set up and Use As mentioned previously, the purpose of using a current interrupter is to stop and start the cathodic protection DC current flow from a rectifier (or other DC source). This can be achieved by installing the interrupter anywhere that results in the DC current being stopped and started by the interrupter. When the DC source is a rectifier, the interrupter can be installed at the following locations on a rectifier circuit: Coarse tap Fine tap Negative side of the rectifier Positive side of the rectifier Rectifier AC power supply Once the current interrupter is installed, set the interrupter(s) to cycle at different ON and OFF cycles. If the ON/OFF cycles are set the same, they may not be distinguishable. A decrease in potential does not mean the rectifier is off. It is critical that all sources of DC current be interrupted simultaneously. On some pipelines, interrupting all Page 11 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

12 current sources may require the use of several synchronous interrupters. Monitor the interrupter for a couple of cycles to ensure proper set up and functionality. If applicable, use appropriate equipment to verify that all current sources are properly interrupted. Lastly, verify the readings are in the desired range. The most commonly used criterion states that adequate CP is achieved with a negative polarized potential of at least 850mV (-850mV) relative to a CuCuSO 4 reference cell. The polarized potential is measured immediately after the interruption of all current sources. Knowledge Identify common methods of determining voltage gradients (IR drop). In the case of a buried pipeline, if the potential of the pipe with respect to a CuCuSO4 reference cell contacting the soil directly above and as close as possible to the pipe is equal to or more negative than -850mV, the -850mV criterion is satisfied and it can be determined that adequate CP has been provided. However, voltage (IR) drops, other than those across the structure-to-electrolyte boundary, must be considered for valid interpretation of the voltage measurement. IR drops, or voltage gradients, are caused by the flow of CP current in the electrolyte, across the pipe coating, and along the pipeline. One way to determine the IR drop is to take the instant OFF potential by briefly switching off or interrupting the CP current. Once the instant OFF potential measurement is taken, it is then compared to the ON potential reading. The difference between the two is the IR or voltage drop. It s important to obtain the instant OFF potential before any depolarization occurs. IR drop disappears immediately after shutting off the current. For this reason, readings must be made before depolarization is significant. Delays can cause the readings to be more positive (+) than the actual polarized potential. Another way to determine IR drop is to measure a pipe-to-soil potential at the pipe-soil interface. This is achieved by placing a reference cell on the surface directly above the pipeline and taking a reading and then placing the reference cell at the pipe-soil interface. The IR drop will be the difference between the two potentials. One way to obtain the pipe-to-soil potential at the pipe-soil interface is by probing the pipeline with a regular probe rod and then sliding a pencil-sized reference cell down the hole until the pipe-soil interface is reached. Note: This method may not be accurate on well-coated pipe. Abnormal Operating Conditions (AOCs) Candidates are required to possess the ability to RECOGNIZE and REACT to the listed AOCs for each task. Be prepared to answer questions concerning additional AOCs that may be relevant. Evaluators may ask questions about AOCs throughout the evaluation. An AOC is defined in 49 CFR and as: A condition identified by the pipeline operator that may indicate a malfunction of a component or deviation from normal operations that may: Page 12 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

13 Indicate a condition exceeding design limits; or Result in a hazard(s) to persons, property, or the environment. Recognize: Unintentional releases, vapors, or hazardous atmosphere could be signs that an abnormal operating condition has occurred. Examples could include, but are not limited to: Blowing gas Puddles Dead vegetation AOC React/Respond: Proper reactions and/or responses to take in the event of an unintentional release, vapors, or hazardous atmosphere include the following: Eliminate potential ignition sources. Move to a safe location. Notify emergency response personnel, as appropriate. Limit access to location, as necessary. Follow appropriate procedures for notification, documentation, and remedial action. Recognize: Material defects, anomalies, or physical damage of pipe or a component that has impaired or is likely to impair the serviceability of the pipeline are abnormal operating conditions. Examples include, but are not limited to: AOC Damaged risers Corrosion Frayed or missing test leads Pipeline and/or components exposed to stray current React/Respond: Proper reactions/responses to take in the event of material defects, anomalies, or physical damage of pipe or a component that has impaired or is likely to impair the serviceability of the pipeline include the following: Determine extent, cause, and potential hazard(s) of defect, anomaly, and/or damage. Mark the location so it may be easily located, as appropriate. Follow appropriate procedures for notification, documentation, and remedial action. AOC Recognize: Failure or malfunction of pipeline component(s) is an abnormal operating condition. Examples could include, but are not limited to: Inoperative rectifier Damaged test station Suspected shorted casing Page 13 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

14 React/Respond: Veriforce TG CCT 407OP Proper reactions/responses to take in the event of a failure or malfunction of pipeline component(s) include the following: Determine extent, cause, and potential hazard(s) of failure or malfunction. Follow appropriate procedures for notification, documentation, and remedial action. Glossary Abnormal Operating Condition Anode Electrical Survey Electrolyte Galvanic Anode CP System Impressed Current CP System A condition identified by the operator that may indicate a malfunction of a component or deviation from normal operations that may indicate a condition exceeding design limits or result in a hazard(s) to persons, property, or the environment. The electrode of an electrochemical cell at which oxidation occurs. Electrons flow away from the anode in the external circuit. Corrosion usually occurs and metal ions enter the solution at the anode. Any technique that involves coordinated electrical measurements taken to provide a basis for deduction concerning a particular electrochemical condition relating to corrosion or corrosion control. A chemical substance containing ions that migrate in an electric field. For the purpose of this standard, electrolyte refers to the soil or liquid adjacent to and in contact with a buried or submerged metallic piping system, including the moisture and other chemicals contained therein. A type of cathodic protection system that takes advantage of the way a dissimilar metal corrosion cell behaves in order to provide cathodic protection to earth-buried or submerged structures. A type of cathodic protection system that takes advantage of the way a dissimilar metal corrosion cell behaves in order to provide cathodic protection to earth-buried or submerged structures. IR Drop The voltage across a resistance in accordance with Ohm s Law. Polarized Potential Resistance The potential across the structure/electrolyte interface that is the sum of the corrosion potential and the cathodic polarization. A material's opposition to the flow of electric current (measured in ohms). Page 14 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016

15 Resistivity The characteristic ability of a material to conduct electricity. Resistivity can be applied to both metallic and non-metallic materials and it is commonly expressed as ohm-centimeters. Stray Current Current through paths other than the intended circuit. Structure-to-Electrolyte Potential or Measurement Test Station Voltage The potential difference between the surface of a buried or submerged metallic structure and electrolyte that is measured with reference to an electrode in contact with the electrolyte. A location or an aboveground appurtenance in which test leads are found to measure cathodic protection. An electromotive force or a difference in electrode potentials expressed in volts. Acronyms AC: alternating current AOC: abnormal operating condition CFR: Code of Federal Regulations CP: cathodic protection CCT: common covered task DC: direct current GPS: global positioning system LCD: liquid crystal display OSHA: Occupational Safety and Health Administration PHMSA: Pipeline and Hazardous Materials Safety Administration RMU: remote monitoring unit Page 15 of 15 Copyright 2016 Veriforce, LLC. All rights reserved. 03/16/2016