Thousands have switched worldwide because this software solves complicated problems.

Deliberately Different

First, our software was created from the beginning to be a cloud-based software product. The need for a desktop local version to facilitate HAZOP and LOPA workshops in remote locations with limited internet access was known from the beginning, so we used the same code to create a desktop version. The two versions work well together for our customers. Then we did something other software vendors would never consider, we gave away the desktop version at no charge.

Second, other PHA software vendors created software that also record studies but the information is saved in a format that was restrictive and difficult to integrate with other software tools. Open PHA was built with a super-set data structure so that the information recorded can be accessed by virtually any other software tool. Designed with integration capability from the beginning makes it easy to build dashboards for critical safety study data and enable word processing software to create custom report using defined wildcards like <%Lopa_Recommendations%>.

Third, we hate software revisions and fees to upgrade so we built Open PHA Cloud and Open PHA Desktop to automatically keep up to date at no charge. Ok, to be fair, the cloud-based software is an annual subscription license so you could argue that the update is included as part of the license.

Finally, we built Open PHA knowing we might not always be the best solution. So, the software does not lock up your study data in an unusable format. In fact, your study data can easily be exported from Open PHA.


Open PHA Cloud and Open PHA Desktop are designed for documenting, analyzing, and maintaining HAZOP, LOPA, and Security PHA Review (SPR) studies.

Open PHA Desktop is a complete PHA software package and is free to download and use on a Windows, Mac, and Linux computer.

Open PHA Cloud is enhanced using internet-based computing. Added features enhance the software and provide access to the other software tools from Kenexis like synchronizing IPFs (an IPF can be a SIF, EPF, MPF, F&G, BPCS, PSV) from Open PHA Cloud with our other software to perform SIL Verification or Fault-tree Analysis.

Both products support customized Templates, Reporting, Risk Matrix, Likelihood Categories, Consequence Categories, Risk Rankings, Nodes, Deviations, HAZOP & LOPA Worksheets, Recommendations, Safeguards, a Parking Lot, and Checklist.

Open PHA Desktop stores files locally on your computer without the need for an internet connection to facilitate work in remote areas. In many cases, this is enough for the small shop or contractor working on a budget. If at some point in the future you want to upgrade to the cloud version, the process is easy and now you can take advantage of the cloud-based storage provided from Open PHA Cloud.

Cloud-based Kenexis software products provide advanced features including secure storage and sharing, and integration with other software Kenexis software. The storage and sharing provide much more than just a file storage system. Our secure cloud-based platform is used to share secure and controllable access for editing or viewing files at a site, with corporate, and even with third parties. Now instead of emailing files and losing version control, everyone throughout the lifecycle can interact with one set of files securely and completely under your control. This is significant when files need to be shared especially outside of your organization with a contract engineering firm.

Open PHA data structure design is fully integrated using an open-source JSON standardized data structure that is revolutionizing PHA documentation. This structure allows the development of tools that can display a single set of data as a HAZOP worksheet, LOPA worksheet, or Bow-tie diagram. Gone are the days of porting and manipulating data and worrying about the consistency of information across multiple files, studies, or data structures. This allows the data from multiple scenarios to be rolled up into easier to use hazard registers and visualized with graphical approaches like bow-tie diagrams, eliminating the frustration of managing replicated data in multiple locations and different languages.

Open PHA supports both explicit and the less common implicit LOPA. In an Explicit LOPA, the team establishes a TMEL target based on a consequence severity, then explicitly defined frequencies of cause, and applies frequency modifiers such as conditional modifiers, enabling events and probabilities of failure for IPL’s. In an implicit LOPA, the team works with the concept of “LOPA credits”.

Open PHA Desktop & Cloud features include:

Features Open PHA Desktop Open PHA Cloud
Configurable HAZOP and LOPA Worksheets
Configurable, Import & Export Risk Criteria
Recommendation Tracking
Deep Copy & Paste, Search & Replace
Implicit & Explicit LOPA Support
Security PHA Review
Cross-Platform Support (Windows/Mac/Linux)
Templating for Nodes and Checklist
Revision Manager
Synchronize IPFs with Vertigo for SIL Verification
One Click Report Generating from Custom *.DOCX Template
Study Content Translation to Other Languages
Bowtie Graphic Generation
Share and Collaborate with Extended Project Teams

Migrating PHA Studies to Open PHA

We realize you have PHA studies on other software including spreadsheets and transitioning to secure cloud-based solutions may seem difficult and time consuming. Let us make that easy for you. We will create the merge tool and port your PHA studies into Open PHA and then you can take advantage of our unified hazard assessment data structure to perform SIL Verification, Fault-tree Analysis, Quantitative Bowtie Analysis, and SIS Life Cycle Management.

Because HAZOP and LOPA studies are the core of process safety documentation, we believe it is important for the information contained within the HAZOP and LOPA to be easily shared across common applications and platforms.  Open PHA was developed to make it easy to pull data from HAZOP and LOPA studies into custom software tools for broad analysis and custom reporting. This philosophy is a paradigm shift in PHA software as file data structures have historically been proprietary to prevent third-party access and discourage the use of competing software tools.

We will help you transition from your existing PHA software to Open PHA software and provide training to make the transition easy.

Security PHA Review Built-In

Security PHA Review (SPR) is an easy method to check safety functions for cybersecurity risks. In Open PHA you can easily turn on the fields to SPR to facilitate a review of a HAZOP and record if the cause and safeguards can be compromised by a hacker or malware, ultimately determining if additional effort is required to secure the scenario against a cybersecurity risk.

Integrated Safety Suite

Kenexis Software runs on our secure cloud servers and is accessed by any licensed user on any computer or tablet through a standard browser. The unique architecture ensures that your software is always available and up to date with the latest performance metrics and resource databases.

Our Process Safety Training Center is also integrated with the software on the Integrated Safety Suite so you can learn how to use the software, learn theory, and process safety engineering all in one place.

Our solution makes it easy for a licensed user to share project information with others including contracts, EPCs, and to leverage Kenexis process safety engineers for project assistance, outsourcing, and verification and certification of your analyses.

  • Compatibility with most browsers in most operating systems
  • Training Center is part of the Integrated Safety Suite
  • Extensive standard and custom equipment databases
  • Detailed technical documentation and help
  • Dedicated help desk and support


In addition to the Support page, there are several training courses on our Integrated Safety Suite. You can request trial license above to gain access to the training.

Once you have access to the trial and Log In, you will find a “Training” button to access the classes.

The software classes above are no charge.

There are also theory and practice classes that require an annual training subscription. Click on Training to learn more about all the online training available.

Open PHA Desktop – Download

There is NO CHARGE for Open PHA Desktop. Just download it using the link above. System requirements are minimal – Open PHA Desktop runs on Mac, Linux, or Windows.

Click here to get started today with Open PHA Desktop for free!

Open PHA Cloud – Trial Request

Open PHA Cloud has an annual subscription price listed below. System requirements – requires a browser on Mac, Linux, or Windows platform, no other requirements.

Click here to request a free 30-day evaluation of Open PHA Cloud

Open PHA Cloud – Pricing

Open PHA Cloud runs in a browser to take advantage of additional cloud-based computing functions to add capabilities that enhance HAZOP and LOPA studies performed in Open PHA Desktop. A concurrent-user license cost $1,250/year. One concurrent license can be used easily in small team, but if you start needing access more when someone else is using the one license, you can add additional licenses at a discount annual subscription rate.

Use the Contact Kenexis link at the top right of this page to request a proposal.


It is always favorable not to mention a competitor. However, in this case we have used our competitors tools for many years and that is the reason we developed Open PHA. Open PHA is very comparable to all of the market leaders providing PHA documentation software, including PHA Works and PHA Pro.

The format and layout of the fields and forms for data entry are all similar.  Open PHA is usually considered easier to use and more aesthetic than PHA Works, and comparable to PHA Pro.  The standard content of studies is very similar between all three of the offerings.

There are two areas of significant difference:

  1. Kenexis Open PHA is free to use, with a single seat enterprise license of Open PHA Could only costing $1,000 per year, which is less than the maintenance costs for a single desktop license of our competitors software.
  2. The other area of difference is in how we handle data.  PHA Pro and PHA Works have customizable database structures that are stored as binary files, whereas Open PHA has a fixed standard database structure that is stored as a plain text file.  Open PHA provides customization by allowing the user to show or hide fields of the database but cannot change them.  While a customizable database structure may seem like an advantage, it usually causes more problems than in solves because it allows every user and consultant working on your plant to implement their own data structure.  If a single plant has many different database structures, it is impossible for them to aggregate all of the data from all of the studies into a single dashboard.  This is only possible with Open PHA Desktop and Cloud because of its fixed, open, and standardized data structure (developed in cooperation with the Purdue Process Safety and Assurance Center of Purdue University).  Additionally, Open PHA has a published structure allowing for advanced programming and compiling of data across thousands of PHA records.

Open PHA Standard has very few, if any, limitations in comparison to its competitors.  Open PHA Cloud includes a variety of additional features, many of which are not available at all from our competition, including language conversion, and bowtie diagram visualization.

Both packages are designed to work together. Let me explain.

The Open PHA Desktop version is a standalone desktop application, which stores files locally on your computer without the need for an internet connection to facilitate work in remote areas.

The licensed open PHA Cloud version of the software runs in a browser and is designed to work with the Desktop versions to provide additional benefits when the user returns to a location where they can access the internet.

Open PHA Desktop & Cloud features include:

  • Configurable HAZOP and LOPA Worksheets
  • Configurable Risk Criteria
  • Recommendation Tracking
  • Deep Copy & Paste
  • Search & Replace
  • Implicit & Explicit LOPA Support
  • Cross-Platform Support (Windows/Mac/Linux)

Open PHA Cloud added features:

  • Requires Internet Connection
  • Study / Facility Dashboard
  • Revision Manager
  • Integration with Vertigo SIS Lifecycle Management
  • One Click Report Generating from Custom *.DOCX Template
  • Study Content Translation
  • Bowtie Generation
  • PHAWorks Import
  • Share and Collaborate with Project Teams

Putting the software through its paces can be done very easily, at no cost.

You simply need to go to the Open PHA software page on our web site and download Open PHA Desktop version of the software at no cost.

You can also request a 30-day trial license of Open PHA Cloud on the same page.

Yes, both versions of Open PHA are updated frequently and actively maintained.  Our software is developed using a CI/CD process meaning updates come more frequently that with legacy desktop software.

Open PHA Cloud will always be up to date as it is a web application.

Open PHA Desktop will check for updates when you open the application if you are connected to the internet.  If an update is found it will download it in the background and install the update the next time Open PHA is closed.

There is no end-of-life plan for Open PHA.

The software is still early in its lifecycle (launched in 2017) and we are actively introducing new features.

In Open PHA Cloud, licensing is done under a concurrent user licensing model.

Concurrent licensing allows any number of users access to the software simultaneously up to the number of concurrent user licenses that you purchase.

Unlicensed, view-only access is free and unlimited. You set up a user account or invite a user for anyone who you would like to have view-only access.

Concurrent user model only applies to users who need editor privileges.

The two versions of Open PHA are intended to be used together.

Open PHA Desktop provides the basic functionality you would be expected to need to during a facilitation session without the need for an internet connection.

Open PHA Cloud provides additional features only available in the Kenexis Integrated Safety Suite like our premium reporting tools, dashboard, integration with SIS Lifecycle Management software, revision management, bowtie diagram generation, etc.

The way that product is intended to be used is for Open PHA Desktop to be used during a facilitation, where internet connection may be unreliable or unavailable, then for the study to be uploaded to Open PHA Cloud when you are back in the office and have reliable internet for finalizing the study and generating a report.  In addition, read-only access to Open PHA Cloud is no-cost, so you can share access to your studies with colleagues and clients easily without having to worry about someone modifying of deleting files.  This is how our engineers and Kenexis use of the software and how I suspect most of our users are using it as well.

To move studies between the desktop and the cloud, you can use the study import/export tool described in section 3.2.3 of the KISS Project Manager User’s manual at the following link.

Additionally, if you are revalidating an existing study, you can “import and a working revision” from the premium tools menu in Open PHA cloud.  This overwrites the currently working revision of a study as described in Section 5.5 of the Open PHA User’s Manual at the following link.

No, our software is not tied to Excel or Microsoft in any way.  In fact, Open PHA Desktop is cross-platform. It runs on Mac and Linux as well.

Open PHA Desktop and Cloud are integrated HAZOP and LOPA software used to record HAZOP and LOPA to determine SIL requirements in accordance with IEC 61511.  However, Open PHA alone does not provide all of the functionality required to comply with IEC 61511.  Open PHA Cloud is integrated with our SIS Lifecycle Management software Vertigo.  While Open PHA Desktop can be used for SIL determination, Vertigo can be used to perform the remaining SIS Lifecycle tasks like SIL Verification, SRS Development and bypass/testing tracking during the operational phases of the lifecycle.  Our Vertigo software is built around and implements the recommended practices from ISA on implementation of the IEC/ISA 61511 standard.

Our platform can provide the functionality you have described.

Open PHA software provides the HAZOP, LOPA and SIL determination functionality.

In addition, Open PHA Cloud is integrated with our Vertigo SIS Lifecycle Management software. Vertigo software extends the functionality of Open PHA Cloud to allow you to perform SIL Verification calculations, develop Safety Requirement Specifications and track the performance of a Safety Instrumented System through the life of the system.

Unfortunately, PHA-Pro is a proprietary software and Kenexis do not have the ability to read those files.

Open PHA supports translations to languages automatically. This is done by looking at the default language for your operating system or your web browser.

There is not a way for the user to manually change the language.

Currently we have support for three languages: English, Chinese and Portuguese.

We support Chinese and Portuguese because there is high demand for our software in China and Brazil where many users do not speak English as a second language.

If you have another language needed, please let us know using the Contact section at the bottom of this page and we will try to accommodate.

You can share your desktop with others using any type of remote conferencing.
Open PHA Cloud, verrsus Open PHA Desktop, adds additional premium features listed below.
Open PHA Cloud added features:
  • Requires Internet Connection
  • Study / Facility Dashboard
  • Revision Manager
  • Integration with Vertigo SIS Lifecycle Management
  • One Click Report Generating from Custom *.DOCX Template
  • Study Content Translation
  • Bowtie Generation
  • PHAWorks Import
  • Share and Collaborate with Project Teams

The last item “Share and Collaborate with Project Teams” is designed to facilitate corporate settings where multiple people want to review and alter findings, recommendations, etc.

If you use Open PHA Cloud for a meeting, you still share your desktop via the web conferencing tool you use like Microsoft Teams or Zoom. But, you will be sharing a browser session requiring an Internet connection the entire time.
We suggest you use Open PHA Desktop for the actual PHA facilitation and recording, that is why it was created as a no-cost download. Then later if you want the added features, you can upgrade to Open PHA Cloud for the added features.

PHA Pro files can be converted to Open PHA.  Kenexis offers a data migration service to assist with this process.  Because the data structure of PHA Pro files can be modified and there are so many different worksheet templates out there, Kenexis does not have a “generic” tool to convert the files.  Instead we work with you to build a data migration tool customized to ensure that your data migration happens with minimal/zero data loss.

Both the Desktop and Cloud versions of Open PHA allow you to customize the risk matrix and risk criteria for your study.  Open PHA supports 5 risk ranking categories (safety, environment, asset, community, and reputation).  Each category can be customized as needed.  You can learn more about how to customize the risk criteria at the video link below.

Using Open PHA – Section 4.1 – Risk Criteria Overview – YouTube

Using Open PHA – Section 4.2 – Likelihood Categories – YouTube

Using Open PHA – Section 4.3 – Consequence Categories – YouTube

Using Open PHA – Section 4.4 – Risk Rankings – YouTube

Using Open PHA – Section 4.5 – Risk Matrix – YouTube

Open PHA can calculate risk ranking before safeguards, after safeguards, and after recommendations.  In the PHA (HAZOP) Worksheet, the is done the traditional (qualitative) way, where the likelihood is based on the judgment of the PHA team.  Open PHA is an integrated PHA/LOPA application which means that for each PHA scenario, you can also have a linked LOPA scenario.  If a PHA scenario is marked as requiring LOPA on the PHA Worksheet it will then appear on the LOPA Worksheet where the scenario can be analyzed quantitatively, considering the frequency of the cause and probability of failure for each safeguard/IPL.

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