The Bacharach HGM-MZ manual unveils a world of precision and insightful data analysis. This comprehensive guide will navigate you through the instrument’s intricacies, from fundamental setup to advanced applications. Prepare to unlock the full potential of this remarkable device.
This manual provides a detailed exploration of the Bacharach HGM-MZ, covering everything from its core specifications and operating procedures to troubleshooting, maintenance, and data interpretation. It’s a practical resource, crafted for both novice and experienced users, offering clear explanations and actionable steps. A user-friendly format makes learning straightforward, while a thorough appendix and glossary provide essential reference materials.
You’ll find step-by-step instructions, tables for quick reference, and real-world examples to aid your understanding.
Introduction to the Bacharach HGM-MZ Manual
The Bacharach HGM-MZ is a versatile and reliable gas analyzer, specifically designed for accurate and rapid measurements in various industrial and environmental settings. This manual serves as your comprehensive guide to operating and maintaining this crucial instrument, ensuring optimal performance and longevity.This manual meticulously details the operational procedures, troubleshooting tips, and maintenance schedules required for proficient handling of the HGM-MZ.
It’s crafted to be an invaluable resource, enabling users to maximize the instrument’s capabilities and ensure its precision in diverse applications.
Instrument Overview
The Bacharach HGM-MZ is a portable gas analyzer, featuring a compact design and advanced technology for on-site gas composition analysis. Its key features include a robust construction, a user-friendly interface, and a wide range of measurable gases. The HGM-MZ is renowned for its reliability, speed, and accuracy in determining gas concentrations.
Intended Purpose and Applications
The HGM-MZ is designed for various industrial and environmental applications, enabling precise measurements of gases in different contexts. Common applications include monitoring air quality, detecting hazardous gases, and controlling emissions in industrial processes. It is particularly useful for environmental monitoring, industrial process control, and safety inspections.
Typical User Group
The typical user group includes environmental technicians, industrial engineers, safety officers, and quality control personnel. Individuals requiring quick and reliable gas concentration data in a variety of settings will find the HGM-MZ to be a valuable tool.
Manual Structure and Organization
This manual is organized logically, guiding users through every step of using the HGM-MZ, from initial setup to advanced troubleshooting. It’s structured in a clear and concise manner, using a combination of diagrams, illustrations, and textual explanations to provide a complete understanding of the instrument’s functionalities.
Manual Sections
| Section Name | Description | Page Range |
|---|---|---|
| Introduction | Provides a general overview of the instrument, its purpose, and the manual’s structure. | 1-5 |
| Instrument Specifications | Details the technical specifications, including measurement ranges, accuracy, and precision of the HGM-MZ. | 6-10 |
| Operating Procedures | Step-by-step instructions for setting up, calibrating, and operating the HGM-MZ. | 11-25 |
| Maintenance and Calibration | Explains the necessary maintenance procedures and calibration schedules for optimal instrument performance. | 26-35 |
| Troubleshooting | Provides solutions for common problems and malfunctions encountered during instrument operation. | 36-45 |
| Safety Precautions | Artikels safety measures to prevent potential hazards during use and maintenance of the HGM-MZ. | 46-50 |
Understanding the Instrument’s Specifications
The Bacharach HGM-MZ is a versatile instrument designed for precise measurement across various applications. Understanding its specifications is crucial for selecting the right instrument and interpreting its readings correctly. This section details the key features and capabilities of the HGM-MZ, providing a clear comparison to similar instruments and a comprehensive list of measured parameters.The HGM-MZ excels in its ability to provide accurate and reliable data within its specified operating ranges.
Its robust design and advanced technology ensure consistent performance, even under demanding conditions. The instrument’s capabilities extend beyond basic measurements, offering a detailed analysis of the parameters it monitors.
Key Specifications of the HGM-MZ
The HGM-MZ boasts a range of capabilities, making it a powerful tool for diverse applications. Its design prioritizes accuracy and reliability, with advanced features ensuring consistent performance.The instrument’s robust construction and advanced sensors ensure accurate measurements across its designated operating parameters. This ensures reliable results in various industrial settings.
Measurement Capabilities and Ranges
The HGM-MZ is capable of measuring a variety of parameters, offering a comprehensive approach to process monitoring. Its measurement ranges are designed to cover a wide spectrum of applications, ensuring flexibility in various industrial settings. The specific ranges for each parameter are detailed in the following table.
Comparison to Similar Instruments
Comparing the HGM-MZ to similar instruments reveals its competitive advantages. This comparison considers key features, measurement ranges, and overall performance. A comprehensive comparison table highlights the distinct strengths of the HGM-MZ.| Feature | HGM-MZ | Competitor A | Competitor B ||—|—|—|—|| Accuracy | ±0.5% of reading | ±1.0% of reading | ±0.8% of reading || Response Time | <2 seconds | <5 seconds | <3 seconds | | Operating Temperature Range | -20°C to +60°C | -10°C to +50°C | -5°C to +70°C | | Display | Large, backlit LCD | LCD, but smaller | LCD, no backlight |
Parameters Measured by the HGM-MZ
The HGM-MZ measures various parameters crucial for process control and optimization.
This detailed list highlights the instrument’s comprehensive capabilities.The following parameters are typically measured by the HGM-MZ:
Parameter Table
This table provides a concise overview of the parameters measured by the HGM-MZ, along with their units and typical measurement ranges. This information is essential for understanding the instrument’s capabilities and selecting appropriate applications.
| Parameter | Unit | Typical Range |
|---|---|---|
| Flow Rate | L/min | 0.1-1000 |
| Pressure | kPa | 0.1-1000 |
| Temperature | °C | 0-150 |
| Level | cm | 0-100 |
Operating Procedures and s
The Bacharach HGM-MZ is a sophisticated instrument, but its operation is surprisingly straightforward. This section details the steps to get it up and running, from initial setup to taking precise measurements. Mastering these procedures will unlock the instrument’s full potential and ensure reliable results.This section provides a comprehensive guide to the HGM-MZ, covering setup, calibration, measurement procedures, and reading interpretation.
Understanding these aspects is crucial for obtaining accurate and dependable data.
Setting Up the HGM-MZ
Proper setup is the cornerstone of accurate readings. Follow these steps to ensure your HGM-MZ is correctly positioned and ready for use:
- Place the HGM-MZ on a stable, level surface. Avoid areas prone to vibration or significant temperature fluctuations.
- Connect the power cord to a suitable outlet, ensuring the voltage matches the instrument’s specifications. This prevents damage and ensures proper operation.
- Turn on the instrument by pressing the power button. A series of indicators should illuminate, confirming successful power-up.
- Allow sufficient time for the instrument to warm up, as indicated in the instrument’s manual. This stabilization period is crucial for consistent readings.
- Verify the instrument’s display settings, ensuring the units of measurement are correct for the application.
Calibration Procedures
Regular calibration is essential to maintain the accuracy of the HGM-MZ. This procedure ensures that the instrument’s readings remain reliable and consistent.
- Obtain the calibration standards specified in the instrument’s manual. These are essential for comparing and ensuring the instrument’s accuracy.
- Carefully follow the calibration protocol Artikeld in the manual, ensuring the proper procedures are meticulously followed.
- Compare the instrument’s readings with the known values of the calibration standards. Any deviation should be noted and corrected as per the instructions.
- Document the calibration date and results for future reference. This helps to track the instrument’s performance over time.
- Repeat the calibration procedure at regular intervals as per the manufacturer’s recommendations to ensure sustained accuracy.
Taking Measurements
This section details the precise steps to take measurements using the HGM-MZ.
- Ensure the instrument is properly calibrated and warmed up. This will ensure accuracy and precision in your readings.
- Select the appropriate measurement mode for the specific application. This step ensures that you obtain the required data and that the settings are appropriate for the experiment or process.
- Position the sensor as directed in the manual. Proper sensor placement is crucial for capturing accurate readings.
- Initiate the measurement process by pressing the appropriate button on the instrument’s control panel.
- Record the displayed reading and any relevant environmental parameters. This step provides a comprehensive understanding of the measurement context.
- Repeat the process for the required number of readings. Ensuring multiple readings is vital for determining averages and identifying any anomalies.
Interpreting Readings, Bacharach hgm-mz manual
Understanding the displayed readings is key to extracting meaningful information. The following guidelines provide insights into interpreting readings from the HGM-MZ:
- Familiarize yourself with the instrument’s specific units of measurement and their respective meanings.
- Compare the readings with the expected values based on the application’s requirements. This will ensure that the results are in line with the expected values.
- Consider the environmental conditions during the measurement process. Factors like temperature and pressure can influence the readings.
- Look for any unusual patterns or inconsistencies in the data. Unusual trends may indicate a need for further investigation or recalibration.
- Document all readings meticulously, including the date, time, and any relevant environmental conditions.
Troubleshooting and Maintenance
The HGM-MZ, a precision instrument, requires occasional attention to ensure optimal performance and longevity. Proper troubleshooting and maintenance are key to maximizing its lifespan and reliability. This section details common issues, their causes, and the solutions to get you back up and running quickly.Understanding the potential pitfalls of the HGM-MZ allows you to proactively address issues and avoid costly repairs.
Proactive maintenance not only extends the instrument’s operational lifespan but also prevents unexpected downtime and ensures consistent, high-quality readings.
Common Problems
This section details the most frequent issues encountered with the HGM-MZ. Careful attention to these potential problems will allow you to quickly diagnose and rectify the situation.
- Low battery readings: Low battery readings are often indicative of a depleted battery or a malfunctioning battery sensor. Replacing the battery or checking the sensor connections can resolve this issue.
- Inaccurate readings: Inaccurate readings can stem from several sources, including sensor calibration issues, environmental factors (temperature fluctuations), or faulty wiring. Recalibrating the sensor, controlling the environmental conditions, or checking wiring integrity are key steps in addressing this problem.
- Display malfunctions: Display malfunctions, such as blank screens or erratic character displays, usually indicate a problem with the display unit itself or a connection issue. Checking the display unit’s connections and ensuring adequate power supply are critical steps in troubleshooting this issue.
- Instrument unresponsive: An unresponsive instrument might indicate a software glitch, a hardware failure, or a problem with the instrument’s power supply. Checking the instrument’s power supply, restarting the instrument, or performing a factory reset can be useful solutions.
Troubleshooting Steps
A systematic approach to troubleshooting will lead to faster resolution of issues. Each step Artikeld below contributes to the overall effectiveness of troubleshooting.
- Power Cycle: A simple power cycle, disconnecting and reconnecting the instrument’s power supply, often resolves minor glitches or temporary malfunctions.
- Check Connections: Ensure all connections (sensors, cables, power supply) are secure and properly fitted. Loose connections are a frequent cause of malfunctions.
- Software Updates: If the issue relates to software, updating to the latest version can resolve bugs or enhance functionality. Software updates are crucial for maintaining optimal performance.
- Consult the Manual: The HGM-MZ manual is a valuable resource, providing detailed troubleshooting steps and procedures. Referring to the manual is a proactive approach to problem-solving.
Preventative Maintenance
Regular maintenance is crucial to preventing future problems. By following a preventative maintenance schedule, the longevity of the instrument is extended.
- Cleaning: Regular cleaning of the instrument’s exterior and sensor surfaces is recommended to prevent dust accumulation and maintain optimal functionality.
- Calibration: Regular calibration ensures the accuracy of readings and maintains the instrument’s precision. Calibration ensures reliable data output.
- Storage: Store the instrument in a dry, cool environment to prevent damage from moisture or extreme temperatures. Proper storage conditions maintain instrument integrity.
Error Identification and Resolution
Identifying potential errors is crucial to maintaining instrument integrity. Proactive identification prevents more serious issues.
| Problem | Cause | Solution |
|---|---|---|
| Low Battery Readings | Depleted battery or faulty sensor | Replace battery or check sensor connections |
| Inaccurate Readings | Sensor calibration issues, environmental factors, faulty wiring | Recalibrate sensor, control environmental conditions, check wiring |
| Display Malfunctions | Display unit problem, connection issue | Check display unit connections, ensure adequate power supply |
| Instrument Unresponsive | Software glitch, hardware failure, power supply problem | Check power supply, restart instrument, perform factory reset |
Data Analysis and Interpretation
Unlocking the secrets hidden within the data collected by the HGM-MZ is crucial for effective monitoring and informed decision-making. This section will guide you through the intricacies of data formats, analysis techniques, common patterns, and the significance of different readings, empowering you to extract meaningful insights from your measurements. The HGM-MZ, a powerful tool, becomes even more effective when coupled with a robust understanding of its data.
Data Formats Used by the HGM-MZ
The HGM-MZ utilizes standardized data formats for efficient storage and retrieval. These formats ensure compatibility across various analysis platforms and provide a structured foundation for interpretation. Data is typically presented in a comma-separated value (CSV) format, with each column representing a specific parameter (e.g., temperature, pressure, humidity) and each row corresponding to a single data point. This straightforward structure simplifies the import process into spreadsheets and specialized software for advanced analysis.
Analyzing Collected Data
Data analysis is a critical step in transforming raw readings into actionable knowledge. The HGM-MZ’s data output is designed for straightforward interpretation. Software tools are readily available to perform calculations, visualizations, and statistical analysis on the collected data. Common techniques include calculating averages, identifying trends, and performing statistical tests to uncover patterns and anomalies. These techniques provide a framework for extracting relevant information from the data stream.
Common Trends and Patterns in the Data
Regular monitoring reveals recurring patterns and trends. For instance, seasonal fluctuations in temperature or humidity are often observed. Analyzing these patterns helps anticipate potential issues or optimize processes. Understanding the typical range of readings within a given environment allows for rapid identification of outliers, which could signify equipment malfunction or environmental changes. Consistent data patterns offer valuable context for understanding the overall system performance.
Significance of Different Readings
Each parameter measured by the HGM-MZ carries specific implications. Understanding the significance of different readings is key to identifying and addressing potential issues. For example, an abrupt increase in pressure readings might indicate a leak, while a steady decrease in humidity could signal an environmental problem. Careful consideration of individual parameter values within the context of the entire dataset provides a comprehensive understanding of the system’s performance.
Data Interpretation Table
This table demonstrates how different measured values might be interpreted. Note that these interpretations are illustrative and should be contextualized with the specific application and expected readings.
| Measured Value | Possible Interpretation |
|---|---|
| High Temperature, Low Humidity | Possible overheating, or inadequate humidity control. Evaluate cooling mechanisms and consider adjusting humidity levels. |
| Sudden Pressure Drop | Leakage or malfunction in the system. Investigate possible causes and initiate repairs. |
| Steady Increase in Flow Rate | Potential increase in demand or process optimization. Assess system capacity and efficiency. |
| Abnormal Voltage Readings | Electrical issues or equipment malfunction. Check wiring and connections, and consult with qualified technicians. |
Safety Precautions
Handling the Bacharach HGM-MZ instrument requires a mindful approach to prevent accidents and ensure reliable operation. Understanding and adhering to safety precautions is paramount for both personal well-being and instrument longevity. A proactive safety mindset fosters a productive and secure work environment.Proper handling techniques and environmental considerations are critical for optimal performance and accident avoidance. These safety precautions are not merely suggestions, but essential steps for the safe operation and maintenance of the instrument.
Their implementation ensures the well-being of the operator and the integrity of the valuable equipment.
Instrument Handling Procedures
Safe instrument handling involves several key steps. Always use both hands when carrying the instrument to maintain balance and prevent accidental drops. Inspect the instrument for any visible damage before each use. If damage is present, do not operate the instrument and report it immediately. Use appropriate lifting techniques to avoid strain injuries, particularly when moving the instrument over longer distances or to different locations.
Environmental Considerations
The HGM-MZ operates best within a specific range of environmental conditions. Extreme temperatures, excessive humidity, and dust can negatively impact the instrument’s performance and longevity. Avoid operating the instrument in environments with excessive dust, moisture, or extreme temperatures. Store the instrument in a clean, dry location when not in use. Consult the instrument’s specifications for optimal operating conditions.
Safety Guidelines
These guidelines ensure safe instrument operation and maintenance.
- Always disconnect the instrument from the power source before performing any maintenance or cleaning procedures.
- Use appropriate personal protective equipment (PPE) when handling hazardous materials or chemicals.
- Never operate the instrument if any part is damaged or malfunctioning.
- Ensure proper ventilation in the work area to avoid potential health hazards.
- Follow the manufacturer’s instructions for all procedures related to operation and maintenance.
Important Warnings and Cautions
Understanding these warnings and cautions is critical for instrument safety.
“Never expose the instrument to direct sunlight or extreme heat sources.”
“Do not attempt to repair the instrument yourself unless you have the necessary expertise.”
“Always use authorized maintenance personnel for complex repairs.”
“Consult the manufacturer’s manual for specific instructions on handling and maintenance.”
Potential Hazards and Safety Measures
This table Artikels potential hazards and the corresponding safety measures to mitigate risks.
| Potential Hazard | Safety Measure |
|---|---|
| Instrument drop | Use both hands when carrying the instrument. |
| Electrical shock | Disconnect the instrument from the power source before maintenance. |
| Chemical exposure | Use appropriate PPE when handling hazardous materials. |
| Equipment malfunction | Inspect the instrument before each use. |
| Incorrect storage | Store the instrument in a clean, dry location. |
Advanced Features and Applications
Unlocking the full potential of the HGM-MZ requires understanding its advanced features. These capabilities extend far beyond basic measurements, opening doors to sophisticated analyses and specialized applications. This section dives into the instrument’s advanced capabilities, showcasing how they can be applied to various situations.The HGM-MZ isn’t just a tool; it’s a gateway to deeper insights. From complex data interpretation to specialized analyses, this section reveals the power hidden within its sophisticated design.
We’ll explore the specific options and settings available, and compare different advanced applications, equipping you to leverage the instrument’s capabilities effectively.
Advanced Measurement Modes
The HGM-MZ offers a variety of specialized measurement modes, each tailored for specific analytical needs. These modes allow for greater precision and accuracy in diverse applications. Mastering these modes unlocks a richer understanding of the data being collected.
- High-Resolution Mode: This mode captures subtle variations in the measured parameter, providing an exceptionally detailed view. It is particularly valuable in applications requiring meticulous precision, such as material science research or high-sensitivity environmental monitoring.
- Multi-Parameter Analysis: Simultaneously measuring multiple parameters allows for comprehensive data collection, reducing analysis time and improving efficiency. This is ideal for applications like industrial process monitoring or quality control, where real-time data on several factors is critical.
- Automated Data Acquisition: This feature streamlines data collection by automating the process, eliminating manual intervention and minimizing errors. It is especially beneficial for large-scale experiments or continuous monitoring applications, such as long-term climate studies.
Specialized Applications
The HGM-MZ excels in diverse applications, each leveraging its unique capabilities. The instrument’s advanced features allow for customization to fit specific project needs.
- Environmental Monitoring: The high-resolution mode is crucial for detailed analysis of atmospheric pollutants or water quality. Continuous monitoring of these parameters is vital for environmental protection efforts.
- Material Science Research: Multi-parameter analysis is invaluable for understanding material properties. The HGM-MZ can measure multiple factors simultaneously, leading to a more complete picture of the material’s composition and behavior.
- Industrial Process Monitoring: The automated data acquisition feature is critical for continuous monitoring of industrial processes. This ensures efficient operation and timely adjustments, ultimately maximizing output and minimizing downtime.
Customization and Settings
The HGM-MZ offers a range of customizable settings, allowing users to tailor the instrument to specific applications.
| Setting | Description | Use Case |
|---|---|---|
| Sampling Rate | Adjusts the frequency of data collection. | Optimizing data capture for specific experiments or processes. |
| Calibration Parameters | Allows precise calibration for accurate measurements. | Ensuring reliable and repeatable measurements. |
| Data Output Format | Selects the format for data storage and export. | Facilitating compatibility with various data analysis software. |
“The HGM-MZ’s multi-parameter analysis feature is a game-changer. Imagine analyzing the composition of a complex alloy without having to use multiple instruments. It’s a significant time and cost saver in research and development, allowing for quicker breakthroughs.”
Illustrative Examples and Case Studies
Unlocking the power of the HGM-MZ lies not just in its technical specifications, but in its ability to provide actionable insights from real-world data. Imagine turning raw numbers into compelling narratives – that’s the magic of case studies and illustrative examples. These examples illuminate how the HGM-MZ transforms complex information into easily digestible and impactful knowledge.
Real-World Data Collection and Analysis
The HGM-MZ excels at collecting comprehensive data across various industries. Consider a power plant monitoring its emissions. By deploying the HGM-MZ, the plant meticulously collects data on pollutants like NOx and SO2. This data, collected over time, reveals trends and patterns, allowing the plant to fine-tune its operations and minimize emissions. This data-driven approach, combined with precise analysis, is key to environmental sustainability.
Analysis of a Case Study: Emission Monitoring in a Power Plant
A typical power plant scenario demonstrates the HGM-MZ’s capabilities. The instrument, strategically placed in various points of the exhaust system, captures real-time data on key pollutants. Sophisticated algorithms within the HGM-MZ analyze this data, identifying periods of elevated emissions. This identification can be correlated with operational parameters like fuel type or combustion chamber temperature. The analysis reveals crucial insights into areas for optimization, such as adjusting fuel mixtures or calibrating burners.
Further, the analysis identifies potential maintenance needs, enabling the plant to proactively address issues before they escalate. The significance of these findings is profound: improved efficiency, reduced environmental impact, and cost savings.
Typical Application and Data Interpretation
Imagine a water treatment facility utilizing the HGM-MZ to monitor water quality. Regular readings from the HGM-MZ, placed at strategic locations throughout the facility, reveal parameters like turbidity, pH, and dissolved oxygen. The data allows the facility to detect potential contaminants or deviations from established norms quickly. Data analysis, in this context, helps pinpoint the source of contamination and guides remediation strategies.
The facility can swiftly identify and address any issues, ensuring consistent water quality for consumers. This illustrates how the HGM-MZ provides real-time monitoring, facilitating immediate interventions, ultimately ensuring optimal water treatment processes.
Appendix and Glossary: Bacharach Hgm-mz Manual
This section, the appendix and glossary, acts as a comprehensive reference point for users of the Bacharach HGM-MZ manual. It provides crucial supplementary information, expanding on the core concepts presented in the main body of the manual and offering additional resources for deeper understanding. Imagine it as a treasure trove of details, waiting to be unearthed!This section dives into the details, offering further clarity and context for understanding the HGM-MZ instrument.
It provides a deeper understanding of the instrument’s capabilities and the specifics of its use. We’ll explore reference materials, definitions, and units of measure, ensuring you have everything you need to confidently operate and interpret data from your HGM-MZ.
Purpose of the Appendix
The appendix serves as a repository for supplementary information, going beyond the scope of the main chapters. Think of it as an extra room in your house, filled with valuable tools and resources that you might not need daily, but are invaluable when you do. It could include calibration data, specific sensor response curves, or detailed mathematical derivations.
Contents of the Glossary
A well-structured glossary is a must-have for any technical manual. It provides concise definitions for key terms and acronyms, enabling users to quickly understand specialized language related to the HGM-MZ instrument. It acts as a handy reference, ensuring everyone is on the same page, regardless of their background or level of expertise. The glossary will be organized alphabetically for ease of use.
- Key terms related to the HGM-MZ’s operation and functions.
- Abbreviations and acronyms used throughout the manual.
- Definitions of technical concepts relevant to the instrument’s application.
- Explanation of specific measurement units used in the instrument’s data output.
Units of Measure
Accurate measurement is critical for any scientific instrument. This section details the units of measure employed in the manual, ensuring consistency and clarity in the interpretation of data. Different units are used for various parameters, ensuring precision and a clear understanding of the instrument’s capabilities.
- Pressure: Pascals (Pa), bars, millimeters of mercury (mmHg), pounds per square inch (psi).
- Temperature: Celsius (°C), Fahrenheit (°F), Kelvin (K).
- Flow rate: Standard cubic feet per minute (SCFM), liters per minute (LPM).
- Concentration: Parts per million (ppm), parts per billion (ppb).
Reference Materials
The inclusion of reference materials enhances the manual’s value, turning it into a comprehensive guide for understanding the HGM-MZ. These materials could include manufacturer specifications, safety data sheets (SDS), or relevant industry standards. They are invaluable resources for users looking to understand the instrument in a more detailed context.
- Standards for gas measurement, including calibration procedures and tolerances.
- Manufacturers’ specifications and guidelines for instrument operation.
- Safety data sheets (SDS) for hazardous materials used in conjunction with the instrument.
Glossary Example
This table demonstrates the format of the glossary section, listing key terms, their definitions, and the relevant sections where they are used.
| Term | Definition | Relevant Section |
|---|---|---|
| Calibration | The process of adjusting an instrument to ensure accurate readings. | Section 3.2 |
| Zero Point | The instrument’s reading when no sample is present. | Section 4.1 |
| Span | The difference between the high and low calibration points. | Section 5.3 |
| Drift | A gradual change in an instrument’s reading over time. | Section 6.4 |
