--- title: Vacuum Pressure vs Absolute and Gauge Pressure description: Explore the difference between absolute pressure, vacuum pressure, and compound pressure and why accurate measurement is crucial for industrial processes. image: https://blog.ashcroft.com/hubfs/Repost-VacuumCompoundAbsolute.BLOG.jpg --- [Skip to main content](https://blog.ashcroft.com/absolute-vacuum-and-compound-pressure#maincontent) Select Region - [US & Canada](https://ashcroft.com) - [Europe](https://ashcroft.eu/) - [China](http://www.ashcroft.com.cn/) - [Mexico & Central America](http://www.ashcroft.com.mx/) - [South America](https://ashcroftsudamericana.com/) - [Brazil](https://ashcroft.com.br/) Login - [Distributor Extranet](https://extranet.ashcroft.com/) - [Product Configurator](https://www.ashcroft.com/my-account/) [Careers](https://www.ashcroft.com/careers) [Contact](https://www.ashcroft.com/contact/) [![ashcroft-logo-lg-2](https://blog.ashcroft.com/hs-fs/hubfs/ashcroft-logo-lg-2.png?width=261&height=60&name=ashcroft-logo-lg-2.png) ![ashcroft-logo-white](https://blog.ashcroft.com/hubfs/assets/images/ashcroft-logo-white.svg)](https://www.ashcroft.com/) Products Pressure Instruments - [Pressure Gauges](https://www.ashcroft.com/products/pressure/pressure-gauges) - [Pressure Switches](https://www.ashcroft.com/products/pressure/pressure-switches) - [Pressure Sensors (Transducers/Transmitters)](https://www.ashcroft.com/products/pressure/pressure-sensors) - [Diaphragm Seals-Isolators](https://www.ashcroft.com/products/pressure/diaphragm-seals-and-isolators) - [Accessories](https://www.ashcroft.com/products/pressure/accessories) - [SMART Transmitter Assemblies](https://www.ashcroft.com/products/pressure/smart-transmitter-assemblies) Temperature Instruments - [Thermometers](https://www.ashcroft.com/products/temperature/thermometers) - [Thermowells](https://www.ashcroft.com/products/temperature/thermowells) - [Temperature Switches](https://www.ashcroft.com/products/temperature/temperature-switches) - [RTDs](https://www.ashcroft.com/products/temperature/rtds) - [Thermocouples](https://www.ashcroft.com/products/temperature/thermocouples) - [Temperature Transmitters](https://www.ashcroft.com/products/temperature/temperature-transmitters/) - [MultiPoint Temperature Sensors](https://www.ashcroft.com/products/temperature/multipoint-temperature-sensors/) - [OEM Temperature Sensors](https://www.ashcroft.com/products/temperature/oem-temperature-sensors) Test Instruments - [Calibrators](https://www.ashcroft.com/products/test-instruments/calibrators/) - [Hand Pumps-Controllers](https://www.ashcroft.com/products/test-instruments/hand-pumps-and-controllers/) - [Hydraulic Testers](https://www.ashcroft.com/products/test-instruments/hydraulic-testers/) - [Test Gauges](https://www.ashcroft.com/products/test-instruments/test-gauges/) Helpful Tools - [Product Documentation](https://www.ashcroft.com/learn/product-documentation/) - [Product & Quality Certifications](https://www.ashcroft.com/about/quality-certifications/) - [Material Selector & Corrosion Guide](https://www.ashcroft.com/webtools/materialselector/) - [Unit Converter](https://www.ashcroft.com/webtools/calculatoruom/) - [Wake Frequency Calculator](https://www.ashcroft.com/webtools/calculatorwf/) - [FAQs](https://www.ashcroft.com/faq/) Keep your critical equipment and processes running with reliable pressure and temperature measurements. [Configure Product Part Number](https://www.ashcroft.com/product-configurator) [Get a Quote](https://www.ashcroft.com/quote) Industries Process Industry Overview - [Solutions for the Process Industry](https://www.ashcroft.com/solutions/process-industry-instrumentation) - [Large Projects/EPC](https://www.ashcroft.com/solutions/process-industry-instrumentation/engineering-procurement-construction-large-projects/) - [Critical Application Solution Experts](https://www.ashcroft.com/solutions/process-industry-instrumentation/critical-application-solution-experts/) - [Distributor Locator](https://www.ashcroft.com/ashcroft-distributors/) Process Industry Solutions - [Chemical & Petrochemical](https://www.ashcroft.com/solutions/process-industry-instrumentation/chemical-process-instrumentation/) - [Food & Beverage](https://www.ashcroft.com/solutions/process-industry-instrumentation-sensors/food-beverage/) - [Metals & Minerals](https://www.ashcroft.com/solutions/process-industry-instrumentation/mining-instruments/) - [Oil & Gas](https://www.ashcroft.com/solutions/process-industry-instrumentation/oil-gas-instrumentation/) - [Pharmaceutical & Biotech](https://www.ashcroft.com/solutions/process-industry-instrumentation/pharmaceutical-and-biotechnology-application-solutions/) - [Power](https://www.ashcroft.com/solutions/process-industry-instrumentation/power-plant-instrumentation/) - [Water & Wastewater](https://www.ashcroft.com/solutions/process-industry-instrumentation/instruments-used-in-water-treatment-plant/) Industrial/OEM Markets Overview - [Solutions for Industrial OEM](https://www.ashcroft.com/solutions/industrial-oem/) - [Custom Engineered Solutions (CES)](https://www.ashcroft.com/solutions/industrial-oem-custom-engineered-solutions/) Industrial/OEM Markets - [HVAC/R](https://www.ashcroft.com/solutions/industrial-oem/hvac-refrigeration-equipment/) - [Hydrogen & Alternative Energu](https://www.ashcroft.com/solutions/industrial-oem/hydrogen-alternative-energy/) - [Industrial Equipment Manufacturer](https://www.ashcroft.com/solutions/industrial-oem/industrial-equipment-manufacturer-supplier/) - [Medical Health & Safety](https://www.ashcroft.com/solutions/industrial-oem/medical-biotechnology-instruments/) - [Process Equipment Manufacturer](https://www.ashcroft.com/solutions/industrial-oem/process-equipment-manufacturer/) - [Semiconductor](https://www.ashcroft.com/solutions/industrial-oem/ultra-high-purity-gas-delivery-semiconductor-manufacturing/) - [Vehicles](https://www.ashcroft.com/solutions/industrial-oem/vehicles-working-machines/) Resources - [Product Documentations](https://www.ashcroft.com/learn/product-documentation/) - [Educational Resources](https://www.ashcroft.com/learn/resource-center/) About - [About](https://www.ashcroft.com/about/) - [Corporate Responsibility](https://www.ashcroft.com/about/corporate-responsibility/) - [Code of Conduct](https://www.ashcroft.com/about/corporate-responsibility/code-of-conduct/) - [Trade Compliance](https://www.ashcroft.com/about/corporate-responsibility/trade-compliance/) - [Product Stewardship](https://www.ashcroft.com/about/corporate-responsibility/product-stewardship/) - [Company News & Events](https://www.ashcroft.com/news-events/) - [Leadership Team](https://www.ashcroft.com/about/leadership/) - [Brands & Trademarks](https://www.ashcroft.com/about/brands-trademarks/) - [Careers](https://www.ashcroft.com/careers/) [Get a Quote](https://sales.ashcroft.com/quote) Products Products [Pressure Instruments](https://www.ashcroft.com) Pressure Instruments [Pressure Gauges](https://www.ashcroft.com/products/pressure/pressure-gauges) [Pressure Switches](https://www.ashcroft.com/products/pressure/pressure-switches) [Pressure Sensors (Transducers/Transmitters)](https://www.ashcroft.com/products/pressure/pressure-sensors) [Diaphragm Seals-Isolators](https://www.ashcroft.com/products/pressure/diaphragm-seals-and-isolators) [Accessories](https://www.ashcroft.com/products/pressure/accessories) [SMART Transmitter Assemblies](https://www.ashcroft.com/products/pressure/smart-transmitter-assemblies) [Temperature Instruments](https://www.ashcroft.com) Temperature Instruments [Thermometers](https://www.ashcroft.com/products/temperature/thermometers) [Thermowells](https://www.ashcroft.com/products/temperature/thermowells) [Temperature Switches](https://www.ashcroft.com/products/temperature/temperature-switches) [RTDs](https://www.ashcroft.com/products/temperature/rtds) [Thermocouples](https://www.ashcroft.com/products/temperature/thermocouples) [Temperature Transmitters](https://www.ashcroft.com/products/temperature/temperature-transmitters/) [MultiPoint Temperature Sensors](https://www.ashcroft.com/products/temperature/multipoint-temperature-sensors/) [OEM Temperature Sensors](https://www.ashcroft.com/products/temperature/oem-temperature-sensors) [Test Instruments](https://www.impactplus.com) Test Instruments [Calibrators](https://www.ashcroft.com/products/test-instruments/calibrators/) [Hand Pumps-Controllers](https://www.ashcroft.com/products/test-instruments/hand-pumps-and-controllers/) [Hydraulic Testers](https://www.ashcroft.com/products/test-instruments/hydraulic-testers/) [Test Gauges](https://www.ashcroft.com/products/test-instruments/test-gauges/) [Helpful Tools](https://www.impactplus.com) Helpful Tools [Product Documentation](https://www.ashcroft.com/learn/product-documentation/) [Product & Quality Certifications](https://www.ashcroft.com/about/quality-certifications/) [Material Selector & Corrosion Guide](https://www.ashcroft.com/webtools/materialselector/) [Unit Converter](https://www.ashcroft.com/webtools/calculatoruom/) [Wake Frequency Calculator](https://www.ashcroft.com/webtools/calculatorwf/) [FAQs](https://www.ashcroft.com/faq/) Industries Industries [Process Industry Overview](https://www.impactplus.com) Process Industry Overview [Solutions for the Process Industry](https://www.ashcroft.com/solutions/process-industry-instrumentation) [Large Projects/EPC](https://www.ashcroft.com/solutions/process-industry-instrumentation/engineering-procurement-construction-large-projects/) [Critical Application Solution Experts](https://www.ashcroft.com/solutions/process-industry-instrumentation/critical-application-solution-experts/) [Distributor Locator](https://www.ashcroft.com/ashcroft-distributors/) [Process Industry Solutions](https://www.impactplus.com) Process Industry Solutions [Chemical & Petrochemical](https://www.ashcroft.com/solutions/process-industry-instrumentation/chemical-process-instrumentation/) [Food & Beverage](https://www.ashcroft.com/solutions/process-industry-instrumentation-sensors/food-beverage/) [Metals & Minerals](https://www.ashcroft.com/solutions/process-industry-instrumentation/mining-instruments/) [Oil & Gas](https://www.ashcroft.com/solutions/process-industry-instrumentation/oil-gas-instrumentation/) [Pharmaceutical & Biotech](https://www.ashcroft.com/solutions/process-industry-instrumentation/pharmaceutical-and-biotechnology-application-solutions/) [Power](https://www.ashcroft.com/solutions/process-industry-instrumentation/power-plant-instrumentation/) [Water & Wastewater](https://www.ashcroft.com/solutions/process-industry-instrumentation/instruments-used-in-water-treatment-plant/) [Industrial/OEM Markets Overview](https://www.impactplus.com) Industrial/OEM Markets Overview [Solutions for Industrial OEM](https://www.ashcroft.com/solutions/industrial-oem/) [Custom Engineered Solutions (CES)](https://www.ashcroft.com/solutions/industrial-oem-custom-engineered-solutions/) [Industrial/OEM Markets](https://www.impactplus.com) Industrial/OEM Markets [HVAC/R](https://www.ashcroft.com/solutions/industrial-oem/hvac-refrigeration-equipment/) [Hydrogen & Alternative Energu](https://www.ashcroft.com/solutions/industrial-oem/hydrogen-alternative-energy/) [Industrial Equipment Manufacturer](https://www.ashcroft.com/solutions/industrial-oem/industrial-equipment-manufacturer-supplier/) [Medical Health & Safety](https://www.ashcroft.com/solutions/industrial-oem/medical-biotechnology-instruments/) [Process Equipment Manufacturer](https://www.ashcroft.com/solutions/industrial-oem/process-equipment-manufacturer/) [Semiconductor](https://www.ashcroft.com/solutions/industrial-oem/ultra-high-purity-gas-delivery-semiconductor-manufacturing/) [Vehicles](https://www.ashcroft.com/solutions/industrial-oem/vehicles-working-machines/) Resources Resources [Product Documentations](https://www.ashcroft.com/learn/product-documentation/) [Educational Resources](https://www.ashcroft.com/learn/resource-center/) About About [About](https://www.ashcroft.com/about/) [Corporate Responsibility](https://www.ashcroft.com/about/corporate-responsibility/) [Code of Conduct](https://www.ashcroft.com/about/corporate-responsibility/code-of-conduct/) [Trade Compliance](https://www.ashcroft.com/about/corporate-responsibility/trade-compliance/) [Product Stewardship](https://www.ashcroft.com/about/corporate-responsibility/product-stewardship/) [Company News & Events](https://www.ashcroft.com/news-events/) [Leadership Team](https://www.ashcroft.com/about/leadership/) [Brands & Trademarks](https://www.ashcroft.com/about/brands-trademarks/) [Careers](https://www.ashcroft.com/careers/) Select Region Select Region [US & Canada](https://ashcroft.com) [Europe](https://ashcroft.eu/) [China](http://www.ashcroft.com.cn/) [Mexico & Central America](http://www.ashcroft.com.mx/) [South America](https://ashcroftsudamericana.com/) [Brazil](https://ashcroft.com.br/) Login Login [Distributor Extranet](https://extranet.ashcroft.com/) [Product Configurator](https://www.ashcroft.com/my-account/) [Careers](https://www.ashcroft.com/careers) [Contact](https://www.ashcroft.com/contact/) [Get a Quote](https://sales.ashcroft.com/quote) [«  View All Articles](https://blog.ashcroft.com/) ![Paul Francoletti, Director of Product Sales – Mechanical's headshot](https://blog.ashcroft.com/hs-fs/hubfs/paulfrancoletti-1.jpg?width=50&height=50&name=paulfrancoletti-1.jpg) **By:** [Paul Francoletti](https://blog.ashcroft.com/author/paul-francoletti) Director of Product Sales – Mechanical **Published on:** February 5th, 2024 **Last updated on:** May 20th, 2026 **Topics:** [pressure gauge](https://blog.ashcroft.com/topic/pressure-gauge) [absolute pressure](https://blog.ashcroft.com/topic/absolute-pressure) [vacuum pressure](https://blog.ashcroft.com/topic/vacuum-pressure) [compound pressure](https://blog.ashcroft.com/topic/compound-pressure) [gauge pressure](https://blog.ashcroft.com/topic/gauge-pressure) **Share:** [mailto:?subject=Vacuum+Pressure+vs+Absolute+and+Gauge+Pressure&body=https://blog.ashcroft.com/absolute-vacuum-and-compound-pressure](mailto:?subject=Vacuum+Pressure+vs+Absolute+and+Gauge+Pressure&body=https://blog.ashcroft.com/absolute-vacuum-and-compound-pressure) Subscribe Never miss a blog post! Subscribe now and get the latest blog posts delivered straight to your inbox. # Vacuum Pressure vs Absolute and Gauge Pressure Print/Save as PDF ![Paul Francoletti, Director of Product Sales – Mechanical's headshot](https://blog.ashcroft.com/hs-fs/hubfs/paulfrancoletti-1.jpg?width=50&height=50&name=paulfrancoletti-1.jpg) **By:** [Paul Francoletti](https://blog.ashcroft.com/author/paul-francoletti) Director of Product Sales – Mechanical **Published on:** February 5th, 2024 **Last updated on:** May 20th, 2026 **Topics:** [pressure gauge](https://blog.ashcroft.com/topic/pressure-gauge) [absolute pressure](https://blog.ashcroft.com/topic/absolute-pressure) [vacuum pressure](https://blog.ashcroft.com/topic/vacuum-pressure) [compound pressure](https://blog.ashcroft.com/topic/compound-pressure) [gauge pressure](https://blog.ashcroft.com/topic/gauge-pressure) **Share:** [mailto:?subject=Vacuum+Pressure+vs+Absolute+and+Gauge+Pressure&body=https://blog.ashcroft.com/absolute-vacuum-and-compound-pressure](mailto:?subject=Vacuum+Pressure+vs+Absolute+and+Gauge+Pressure&body=https://blog.ashcroft.com/absolute-vacuum-and-compound-pressure) ![Vacuum Pressure vs Compound and Absolute Pressure](https://blog.ashcroft.com/hs-fs/hubfs/Repost-VacuumCompoundAbsolute.BLOG.jpg?width=1600&height=534&name=Repost-VacuumCompoundAbsolute.BLOG.jpg) Vacuum pressure, absolute pressure, and compound pressure gauges each measure pressure differently based on their reference point. Selecting the correct type of pressure gauge is important because the wrong reference can lead to inaccurate readings, poor scale readability, and unreliable process measurements. Different systems, environments, and process conditions require different measurement approaches, and using the wrong gauge can affect both performance and accuracy. Read this article to learn the differences between vacuum pressure, absolute pressure, and compound pressure gauges, how each type works, and when to use them in industrial applications. ## What is the difference between absolute, gauge, and vacuum pressure? Different industrial applications require different pressure references depending on the process conditions and measurement requirements. Mechanical pressure gauges, for example, can be used to measure absolute pressure (relative to a perfect vacuum), vacuum pressure (below atmospheric pressure), and compound pressure (relative to atmospheric and positive pressure).  Here's a closer look at each: - Absolute pressure is measured referenced to absolute vacuum, or zero pressure. Absolute vacuum occurs when air is completely absent. Because it uses absolute zero as the reference point, there is no negative absolute pressure. - Gauge pressure is pressure measured relative to atmospheric pressure, using the surrounding ambient air pressure as the reference point.  - Vacuum pressure is a negative pressure less than atmospheric or barometric pressure, using ambient pressure as the reference. Some applications may also require gauges capable of measuring both positive and negative pressure. These are commonly referred to as compound pressure gauges. *Figure 1. Types of pressure* ![Types of pressure](https://blog.ashcroft.com/hs-fs/hubfs/Types%20of%20pressure.png?width=1212&height=477&name=Types%20of%20pressure.png) What is barometric or atmospheric pressure? Barometric or atmospheric pressure is the ambient air pressure surrounding the earth and is commonly used as the calibration reference for mechanical pressure gauges. Typically, mechanical pressure gauges are measured and calibrated at atmospheric pressure. At sea level, this is approximately 30 inches of mercury or 14.7 psi. It changes based on elevation and weather conditions. On rainy days, barometric pressure falls, while pleasant weather generally causes it to rise. Extreme conditions can significantly affect atmospheric pressure readings. For example, a sealed-case gauge calibrated at sea level may be affected if installed where atmospheric pressure is substantially lower. Because this pressure changes over time and location, gauges calibrated at one atmospheric condition may experience slight accuracy shifts when installed in another environment. ## What instruments are used to measure absolute pressure? Absolute pressure can be measured using mechanical pressure gauges, digital pressure gauges or pressure transducers designed for absolute pressure applications. ### Mechanical pressure gauges can provide an economical absolute pressure option [Mechanical gauges](https://www.ashcroft.com/products/pressure/pressure-gauges/?pageNumber=1&postTypes=product&postsPerPage=12&sortType=menu_order&sortOrder=ASC&tax-pa_measurement-mode=1470&tax-pa_gauge-type=1434) are typically calibrated at atmospheric pressure. When absolute pressure measurement is required, one common approach is to calibrate the gauge at atmospheric pressure and then offset the pointer 14.7 psi upscale at zero pressure. Although this is not considered a true absolute gauge with an isolated pressure chamber, it is often an acceptable and economical solution for many industrial applications. True absolute mechanical gauges with isolated chambers are available but are generally more costly and less commonly used. ### Digital pressure gauges and transducers provide true absolute pressure measurement [Digital pressure gauges](https://www.ashcroft.com/products/pressure/pressure-gauges/?pageNumber=1&postTypes=product&postsPerPage=12&sortType=menu_order&sortOrder=ASC&tax-pa_gauge-type=1435) and [pressure transducers](https://www.ashcroft.com/products/pressure/pressure-sensors/?pageNumber=1&postTypes=product&postsPerPage=12&sortType=menu_order&sortOrder=ASC&tax-pa_measurement=1323) use sensor technology that allows for true absolute pressure measurement. These instruments are used in many applications, including [semiconductor](https://www.ashcroft.com/solutions/industrial-oem/ultra-high-purity-gas-delivery-semiconductor-manufacturing/), [off-highway vehicle](https://www.ashcroft.com/solutions/industrial-oem/vehicles-working-machines), and natural gas applications. *Fig. 2: With standard 0/100 psi gauge pressure*  ![](https://blog.ashcroft.com/hs-fs/hubfs/Figure%201%20gauge%20for%20absolute%20pressure.jpg?width=279&height=259&name=Figure%201%20gauge%20for%20absolute%20pressure.jpg)  *Fig. 3: With 0/100psia absolute pressure* *![](https://blog.ashcroft.com/hs-fs/hubfs/Figure%202%20gauge%20for%20absolute%20pressure.jpg?width=284&height=266&name=Figure%202%20gauge%20for%20absolute%20pressure.jpg)* When to use a vacuum pressure gauge? Use a vacuum pressure gauge when you need to measure pressure below atmospheric pressure.  These gauges are calibrated at atmospheric pressure and read only negative pressure or vacuum conditions.  Vacuum pressure gauge dials typically read counterclockwise. As the vacuum increases, the gauge pointer rotates counterclockwise. On a standard 270-degree dial arc gauge, zero pressure is positioned near the 270-degree location on the dial. *Fig. 4: Vacuum pressure gauge* **![](https://blog.ashcroft.com/hs-fs/hubfs/vacuum.jpg?width=295&height=287&name=vacuum.jpg)** ## What is a compound pressure gauge? A compound pressure gauge measures both positive pressure and vacuum pressure on the same dial. These gauges are commonly used in low-pressure systems and applications where operators need to monitor both vacuum and positive pressure conditions with a single instrument. Standard positive-pressure gauges are generally not damaged if a full vacuum is applied. However, when an application requires the dial to display both positive and negative pressure readings, a compound pressure gauge is typically used. The pointer moves clockwise when measuring positive pressure and counterclockwise when measuring vacuum or negative pressure. *Fig. 5: Compound pressure gauge* ![](https://blog.ashcroft.com/hs-fs/hubfs/compound.jpg?width=298&height=290&name=compound.jpg) ## When should you use absolute, vacuum, or compound pressure gauges? The correct pressure gauge depends on whether the application requires measurement relative to atmospheric pressure, below atmospheric pressure, or referenced to absolute zero. ### 1. Use absolute pressure instruments when you need measurements that are completely independent of changes in atmospheric pressure. Absolute pressure instruments with isolated sensors are commonly used in weather stations and applications where air pressure is used to calculate elevation. Absolute pressure gauges with non-isolated sensors, such as bourdon tube designs, are often used in refineries, petrochemical plants, and chemical processing facilities. ### 2. Vacuum pressure gauges are used in systems that operate below atmospheric pressure Vacuum gauges are used in systems that rely on vacuum pumps to remove pressure. Common applications include many pump systems, refrigeration systems, leak detection equipment, and air conditioning systems. ### 3. Compound pressure gauges are used when both positive and negative pressure must be monitored Compound pressure gauges are commonly used to measure leaks in pressurized lines, HVAC systems, laboratory test chambers, pump systems, and other low-pressure applications where both positive and negative pressures need to be displayed. ## Ready to learn more? Now that you have learned the different types of pressure to measure, let us help you find the right[ pressure gauge range](https://blog.ashcroft.com/select-pressure-gauge-range) for your application. Check out the related resources below or [contact us](https://www.ashcroft.com/contact/) to discuss your process and your measurement needs. In the meantime, feel free to [download our guide](https://sales.ashcroft.com/avoid-pressure-equipment-failure-eb-lp?_ga=2.223066648.2075457622.1658759383-1727663658.1617109357&hsCtaTracking=93688678-bbbb-4592-9ccc-b7174b59f20e%7Cc99f1622-fbc8-48b9-a289-a92b8ddc4c76) to learn how to prevent pressure instrument failure.  [![How to Avoid Pressure Equipment Failure](https://no-cache.hubspot.com/cta/default/4021582/93688678-bbbb-4592-9ccc-b7174b59f20e.png)](https://cta-redirect.hubspot.com/cta/redirect/4021582/93688678-bbbb-4592-9ccc-b7174b59f20e) [Paul Francoletti, Director of Product Sales – Mechanical](https://blog.ashcroft.com/author/paul-francoletti) Paul Francoletti has been with Ashcroft since 2008 and brings extensive experience across EPC and Product Management roles. Throughout his career, he has worked closely with sales teams, channel partners, affiliates, and manufacturing operations to support customer needs and business growth. Paul has also authored numerous educational blog articles, helping readers better understand process and industrial pressure measurement solutions and their real-world applications. Connect: [mailto:paul.francoletti@ashcroft.com](mailto:paul.francoletti@ashcroft.com) Topics: [pressure gauge](https://blog.ashcroft.com/topic/pressure-gauge) [absolute pressure](https://blog.ashcroft.com/topic/absolute-pressure) [vacuum pressure](https://blog.ashcroft.com/topic/vacuum-pressure) [compound pressure](https://blog.ashcroft.com/topic/compound-pressure) [gauge pressure](https://blog.ashcroft.com/topic/gauge-pressure) Don't forget to share this post: ## Related Articles ### [![Compact vs Industrial Low-Pressure Diaphragm Gauges](https://blog.ashcroft.com/hs-fs/hubfs/LP_DiaphramGauges_BLOG_V3.jpg?width=1600&height=534&name=LP_DiaphramGauges_BLOG_V3.jpg) How to Choose a Low-Pressure Diaphragm Gauge June , 2026|4 min. read](https://blog.ashcroft.com/how-to-choose-a-low-pressure-diaphragm-gauge) ### [![Pressure Gauge CASE STUDY](https://blog.ashcroft.com/hs-fs/hubfs/CaseStudy_6-1-26.BLOG.jpg?width=1600&height=534&name=CaseStudy_6-1-26.BLOG.jpg) Improving Pressure Gauge Reliability in Severe Process Applications June , 2026|2 min. read](https://blog.ashcroft.com/improving-pressure-gauge-reliability-in-severe-process-applications) ### [![Negative Pressure Transducers](https://blog.ashcroft.com/hs-fs/hubfs/NegativePressure_BLOG_V2.jpg?width=1600&height=534&name=NegativePressure_BLOG_V2.jpg) How Do I Select a Pressure Transducer for a Negative Pressure System? May , 2026|6 min. read](https://blog.ashcroft.com/how-do-i-select-a-pressure-transducer-for-a-negative-pressure-system) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/UseCase_5-11-26_8008S-H2.BLOG.jpg?width=1600&height=534&name=UseCase_5-11-26_8008S-H2.BLOG.jpg) Improving Reliability in Mobile Hydrogen Systems with High-Pressure Instrumentation May , 2026|1 min. read](https://blog.ashcroft.com/improving-reliability-in-mobile-hydrogen-systems-with-high-pressure-instrumentation) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/GaugeComparison_BLOG.jpg?width=1600&height=534&name=GaugeComparison_BLOG.jpg) Product Comparison: Industrial Pressure Gauges for General and Harsh Applications March , 2026|3 min. read](https://blog.ashcroft.com/product-comparison-industrial-pressure-gauges-for-general-and-harsh-applications) ### [![Food and Beverage Instrumentation](https://blog.ashcroft.com/hs-fs/hubfs/NSF_FoodBev_BLOG.jpg?width=1600&height=534&name=NSF_FoodBev_BLOG.jpg) Food and Beverage Instrumentation: Understanding NSF, 3-A and FDA Requirements March , 2026|4 min. read](https://blog.ashcroft.com/food-grade-pressure-instruments-understanding-nsf-3-a-and-fda-requirements) ### [![Portfolio Management for Compressor Manufacturer](https://blog.ashcroft.com/hs-fs/hubfs/UseCase_3-9-26.BLOG_V2.jpg?width=1600&height=534&name=UseCase_3-9-26.BLOG_V2.jpg) Providing Strategic Portfolio Management for a Compressor Manufacturer March , 2026|2 min. read](https://blog.ashcroft.com/providing-strategic-portfolio-management-for-a-compressor-manufacturer) ### [![Stainless steel vs Brass Material Compatibility](https://blog.ashcroft.com/hs-fs/hubfs/1008_Brs-SS_BLOG_V1.jpg?width=1600&height=534&name=1008_Brs-SS_BLOG_V1.jpg) Why Material Compatibility Matters When Replacing Pressure Instrumentation December , 2025|4 min. read](https://blog.ashcroft.com/why-material-compatibility-matters-when-replacing-pressure-instrumentation) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Basics.BLOG_12-1-25.jpg?width=1600&height=534&name=Basics.BLOG_12-1-25.jpg) Why Should My Pressure Gauge Pointer be in the Center of the Scale? December , 2025|3 min. read](https://blog.ashcroft.com/why-should-my-pressure-gauge-pointer-be-in-the-center-of-the-scale) ### [![What is a Bellows Pressure Gauge](https://blog.ashcroft.com/hs-fs/hubfs/Basics.BLOG_11-10-25.jpg?width=1600&height=534&name=Basics.BLOG_11-10-25.jpg) What is a Bellows Gauge? November , 2025|2 min. read](https://blog.ashcroft.com/what-is-a-bellows-gauge) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Repost-HP_ReedSwitch_BLOG_V1.jpg?width=1600&height=534&name=Repost-HP_ReedSwitch_BLOG_V1.jpg) Product Review: HPS High-Purity Pressure Gauge with Reed Switch November , 2025|2 min. read](https://blog.ashcroft.com/high-purity-pressure-gauge-reed-switch) ### [![How to store your pressure gauge](https://blog.ashcroft.com/hs-fs/hubfs/Repost-Instr.Storage_SOCIAL_V1.jpg?width=1600&height=836&name=Repost-Instr.Storage_SOCIAL_V1.jpg) How To Properly Store Your Pressure Gauge October , 2025|4 min. read](https://blog.ashcroft.com/properly-store-your-pressure-gauge) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/LowPrAssembly_BLOG_V2.jpg?width=1600&height=534&name=LowPrAssembly_BLOG_V2.jpg) Choosing Assemblies for Low-Pressure Applications October , 2025|5 min. read](https://blog.ashcroft.com/choosing-assemblies-for-low-pressure-applications) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/ConnectOptions_BLOG_V2.jpg?width=1600&height=534&name=ConnectOptions_BLOG_V2.jpg) Factors for Choosing a Process Connection for Your Application September , 2025|4 min. read](https://blog.ashcroft.com/how-to-choose-the-right-process-connection) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/PrGaugeRepair_BLOG_V2.jpg?width=1600&height=534&name=PrGaugeRepair_BLOG_V2.jpg) Are Pressure Gauges Repairable? September , 2025|3 min. read](https://blog.ashcroft.com/are-pressure-gauges-repairable) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Repost_1032_1033_BLOG_V1.jpg?width=1600&height=534&name=Repost_1032_1033_BLOG_V1.jpg) Product Review: 1032 & 1033 Sanitary Pressure Gauges September , 2025|3 min. read](https://blog.ashcroft.com/product-review-1032-sanitary-pressure-gauge) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Repost_AmmoniaPlant_BLOG_V1.jpg?width=1600&height=534&name=Repost_AmmoniaPlant_BLOG_V1.jpg) Best Pressure Instruments for Ammonia Plant Applications September , 2025|4 min. read](https://blog.ashcroft.com/pressure-gauges-for-ammonia-plants) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Tri-Clamp_BLOG_V2.jpg?width=1600&height=534&name=Tri-Clamp_BLOG_V2.jpg) Why Use Tri-Clamp Fittings for Hygienic Applications? August , 2025|4 min. read](https://blog.ashcroft.com/why-use-tri-clamp-fittings-for-hygienic-applications) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Basics.BLOG_8-4-25.jpg?width=1600&height=534&name=Basics.BLOG_8-4-25.jpg) How to Select the Right Pressure Gauge Pointer Type? August , 2025|4 min. read](https://blog.ashcroft.com/how-to-select-the-right-pressure-gauge-pointer-type) ### [![Solid-Front Pressure Gauge](https://blog.ashcroft.com/hs-fs/hubfs/Repost-Solid.vs.OpenFront_BLOG_V1.jpg?width=1600&height=534&name=Repost-Solid.vs.OpenFront_BLOG_V1.jpg) Solid-Front Pressure Gauges vs. Open-Front Pressure Gauges July , 2025|3 min. read](https://blog.ashcroft.com/solid-front-open-front-gauges) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/TrueZero_BLOG_V2.jpg?width=1600&height=534&name=TrueZero_BLOG_V2.jpg) What Is a Zero Box vs. a Dial Pin on a Pressure Gauge—and Why It Matters July , 2025|4 min. read](https://blog.ashcroft.com/what-is-a-zero-box-vs-dial-pin-on-a-pressure-gauge) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Repost-T6500_XRABLOG_V1.jpg?width=1600&height=534&name=Repost-T6500_XRABLOG_V1.jpg) Best Pressure Gauges with Overpressure Protection July , 2025|3 min. read](https://blog.ashcroft.com/blog/best-pressure-gauges-for-overpressure-protection) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Repost_8008S_BLOG_V1.jpg?width=1600&height=534&name=Repost_8008S_BLOG_V1.jpg) Product Review: 8008S Stainless Steel Pressure Gauge June , 2025|3 min. read](https://blog.ashcroft.com/8008s-pressure-gauge-review) ### [![](https://blog.ashcroft.com/hs-fs/hubfs/Repost_ProdCompare_5503-04_BLOG_V1.jpg?width=1600&height=534&name=Repost_ProdCompare_5503-04_BLOG_V1.jpg) Differential Pressure Gauge Product Comparison June , 2025|3 min. read](https://blog.ashcroft.com/5503-f5504-differential-pressure-gauges) ### [![Bourdon Tube Construction](https://blog.ashcroft.com/hs-fs/hubfs/Repost_Bourdon_BLOG_V1.jpg?width=1600&height=534&name=Repost_Bourdon_BLOG_V1.jpg) Bourdon Tube Construction Types June , 2025|4 min. read](https://blog.ashcroft.com/bourdon-tube-construction) ![https://f.hubspotusercontent30.net/hubfs/4021582/assets/images/ashcroft-logo-white.svg](https://blog.ashcroft.com/hubfs/assets/images/ashcroft-logo-white.svg) 250 East Main Street Stratford, CT 06614 [800.328.8258](tel:+1800.328.8258) [Contact](https://www.ashcroft.com/contact/) [Learning Center](https://www.ashcroft.com/learn/resource-center) [Blog](https://blog.ashcroft.com/) [Subscribe to Blog](https://sales.ashcroft.com/ashcroft-blog-subscribe) [Facebook](https://www.facebook.com/AshcroftInc) [Instagram](https://www.instagram.com/ashcroftinc/) [LinkedIn](https://www.linkedin.com/company/ashcroft-inc-/) [YouTube](https://www.youtube.com/user/AshcroftInc) [PRODUCTS](https://www.ashcroft.com/products) - [Pressure Instruments](https://www.ashcroft.com/products/#pressure) - [Temperature Instruments](https://www.ashcroft.com/products/#temperature) - [Test Instruments](https://www.ashcroft.com/products/#test-instruments) - [Product Configurator](https://www.ashcroft.com/product-configurator/) - [Product Documentation](https://www.ashcroft.com/learn/product-documentation) - [Pressure Gauge Selection Tool](https://www.ashcroft.com/pressure-gauge-selection-tool/) - [Product & Quality Certifications](https://www.ashcroft.com/about/quality-certifications/) PROCESS INDUSTRY - [Overview](https://www.ashcroft.com/solutions/process-industry-instrumentation/) - [Large Projects/EPC](https://www.ashcroft.com/solutions/process-industry-instrumentation/engineering-procurement-construction-large-projects/) - [Critical Application Solutions Experts (CASE)](https://www.ashcroft.com/solutions/process-industry-instrumentation/critical-application-solution-experts/) - [Distributor Locator](https://www.ashcroft.com/ashcroft-distributors/) INDUSTRIAL/OEM - [Overview](https://www.ashcroft.com/solutions/industrial-oem/) - [Custom Engineered Solutions (CES)](https://www.ashcroft.com/solutions/industrial-oem-custom-engineered-solutions/) COMPANY - [About](https://www.ashcroft.com/about/) - [Corporate Responsibility](https://www.ashcroft.com/about/corporate-responsibility/) - [Code of Conduct](https://www.ashcroft.com/about/corporate-responsibility/code-of-conduct/) - [Trade Compliance](https://www.ashcroft.com/about/corporate-responsibility/trade-compliance/) - [Product Stewardship](https://www.ashcroft.com/about/corporate-responsibility/product-stewardship/) - [Company News & Events](https://www.ashcroft.com/news-events/) - [Careers](https://www.ashcroft.com/careers/) - [Contact](https://www.ashcroft.com/contact/) © 2026 Ashcroft Inc.. All Rights Reserved. [Privacy Statement](https://www.ashcroft.com/privacy-policy/) | [Legal Disclaimer](https://www.ashcroft.com/disclaimer) | [Supplier Terms of Purchase](https://www.ashcroft.com/wp-content/uploads/2026/07/ashcroft-purchase-order-terms-conditions-revh-july26.pdf) | [Terms of Sales](https://www.ashcroft.com/wp-content/uploads/2023/08/terms-of-sale-ashcroft.pdf) | [Privacy Policy](https://www.ashcroft.com) ```json { "@context" : "https://schema.org", "@id" : "https://blog.ashcroft.com/#website", "@type" : "WebSite", "inLanguage" : "en-US", "name" : "Ashcroft Inc.", "potentialAction" : { "@type" : "SearchAction", "query-input" : "required name=search_term_string", "target" : "https://blog.ashcroft.com/search?term={search_term_string}" }, "publisher" : { "@id" : "https://blog.ashcroft.com/#organization" }, "url" : "https://blog.ashcroft.com" } ``` ```json { "@context" : "https://schema.org", "@id" : "https://blog.ashcroft.com/#organization", "@type" : "Organization", "address" : { "@type" : "PostalAddress", "addressCountry" : "US", "addressLocality" : "Stratford", "addressRegion" : "CT", "postalCode" : "06614", "streetAddress" : "250 East Main Street" }, "image" : { "@id" : "https://blog.ashcroft.com/#logo" }, "logo" : { "@id" : "https://blog.ashcroft.com/#logo", "@type" : "ImageObject", "caption" : "Ashcroft Logo", "contentUrl" : "https://4021582.fs1.hubspotusercontent-na1.net/hubfs/4021582/social-suggested-images/sales.ashcroft.comhs-fshubfsashcroft-logo-lg-2.png", "height" : 45, "inLanguage" : "en-US", "url" : "https://4021582.fs1.hubspotusercontent-na1.net/hubfs/4021582/social-suggested-images/sales.ashcroft.comhs-fshubfsashcroft-logo-lg-2.png", "width" : 200 }, "name" : "Ashcroft Inc.", "sameAs" : [ "https://www.facebook.com/AshcroftInc", "https://www.instagram.com/ashcroftinc/", "https://www.linkedin.com/company/ashcroft-inc-/", "https://www.youtube.com/user/AshcroftInc" ], "telephone" : "+18003288258", "url" : "https://blog.ashcroft.com" } ``` ```json { "@context" : "https://schema.org", "@type" : "BlogPosting", "author" : { "@type" : "Person", "name" : "Paul Francoletti, Director of Product Sales – Mechanical", "url" : "https://blog.ashcroft.com/author/paul-francoletti" }, "dateCreated" : "2021-12-10T19:44:29", "dateModified" : "2026-05-20T00:00:00-0400", "datePublished" : "2024-02-05T12:07:41-0500", "description" : "Explore the difference between absolute pressure, vacuum pressure, and compound pressure and why accurate measurement is crucial for industrial processes.", "headline" : "Vacuum Pressure vs Absolute and Gauge Pressure", "image" : [ "https://4021582.fs1.hubspotusercontent-na1.net/hubfs/4021582/Repost-VacuumCompoundAbsolute.BLOG.jpg" ], "inLanguage" : "en", "keywords" : [ "pressure gauge", "absolute pressure", "vacuum pressure", "compound pressure", "gauge pressure" ], "learningResourceType" : "article", "name" : "Vacuum Pressure vs Absolute and Gauge Pressure", "publisher" : { "@type" : "Organization", "logo" : { "@type" : "ImageObject", "url" : "https://4021582.fs1.hubspotusercontent-na1.net/hubfs/4021582/social-suggested-images/sales.ashcroft.comhs-fshubfsashcroft-logo-lg-2.png" }, "name" : "Ashcroft Inc." }, "timeRequired" : "PT3M", "url" : "https://blog.ashcroft.com/absolute-vacuum-and-compound-pressure" } ``` ```json { "@context" : "https://schema.org", "@type" : "Product", "brand" : { "@type" : "Brand", "name" : "Ashcroft" }, "category" : "Pressure Gauges", "description" : "Mechanical and digital pressure instruments for measuring absolute, vacuum, and compound pressure, with guidance on when to use each type.", "manufacturer" : { "@type" : "Organization", "address" : { "@type" : "PostalAddress", "addressCountry" : "US", "addressLocality" : "Stratford", "addressRegion" : "CT", "postalCode" : "06614", "streetAddress" : "250 East Main Street" }, "name" : "Ashcroft Inc." }, "name" : "Ashcroft Pressure Gauges (Absolute, Vacuum & Compound)", "url" : "https://blog.ashcroft.com/absolute-vacuum-and-compound-pressure" } ```