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Operating Instructions: What-If PHA Automated Spreadsheet (v2.0)

✓ Version 2.0 Release • Optimized for Microsoft 365, Excel 2024 & Windows 11

Document Ref: PHA-WIF-UG-001 • Rev. 2.0 • Effective: September 2026 • www.industrydocs.org

Technical documentation and configuration guide for Version 2.0 of the What-If PHA Automated Spreadsheet. Re-engineered for seamless VBA and interactive control resilience in Microsoft 365, Excel 2024, and Windows 11, this guide details site-specific data setup, automated question filtering, and risk worksheet generation.

  1. Video for Introduction to Process Hazard Analysis
  2. Video for What-If PHA Automated Excel Spreadsheet
  3. Chemical Safety Board Videos
  4. Standards for Conducting a PHA
  5. PHA Sample using What-If Methodology
  6. Verify System Requirements, Unblock Archive, Enable ActiveX, and Enable Macros:
    • Operating System: Windows 11 or Windows 10.
    • Supported Excel Versions: Microsoft 365 (Desktop App), Excel 2024, Excel 2021, Excel 2019, or Excel 2016 (32-bit or 64-bit).
    • Mac Compatibility: Requires a Windows hosting environment such as Parallels Desktop for Mac or VMware Fusion running the Windows desktop edition of Excel.
    • Incompatible Platforms: Native Excel for Mac, Excel for the Web (browser), and mobile apps do not support Windows ActiveX controls or VBA automation.
    Important Note for Downloaded Files: Windows automatically marks files downloaded from the web with a security block (Mark of the Web). To prevent Excel from permanently disabling the workbook with a red security banner, you must unblock the downloaded file as shown in step (a) below.
    1. Unblock the Downloaded ZIP File (Recommended before extracting):
      1. Locate the downloaded .zip file in your Downloads folder.
      2. Right-click the .zip file and choose Properties.
      3. On the General tab, at the very bottom under the Security section, check the box labeled "Unblock".
      4. Click Apply, then click OK.
      5. Extract the archive as normal. All files inside will now be unblocked and ready to use.

      Note: If you have already extracted the folder, simply right-click the extracted .xlsm workbook file itself, select Properties, check Unblock, and click OK.

    2. Configure Trust Center Settings for ActiveX and Macros:
      Open Excel and navigate to File > Options > Trust Center > Trust Center Settings... (The interface is identical across Microsoft 365, Excel 2024, 2021, 2019, and 2016):
      1. ActiveX Settings: Click ActiveX Settings in the left pane. Select "Prompt me before enabling all controls with minimal restrictions" and verify "Safe mode" is checked.
        (Note: If set to "Disable all controls without notification", buttons will fail to respond without any warning.)
      2. Macro Settings: Click Macro Settings in the left pane. Select "Disable VBA macros with notification".
        (Enterprise Alternative: Click Trusted Locations in the left pane and add your working folder. Spreadsheets in trusted locations run automated features automatically without prompting.)
      Excel Options Trust Center settings to enable macros for the PHA spreadsheet

      Shown above: Trust Center dialog. ActiveX Settings, Macro Settings, and Trusted Locations are accessible via the left sidebar.


    3. Open Workbook and Click "Enable Content":
      When you open the spreadsheet, if a yellow security message bar appears stating that active content has been disabled, click the "Enable Content" button to initialize the tool:
      Security warning to enable content when opening the PHA automation tool

    💡 Quick Note for Microsoft 365 & Excel 2024 Users (Interactive Controls)

    Modern Microsoft 365 installations include elevated security defaults for interactive worksheet elements (ActiveX buttons and dropdowns). To ensure seamless one-click automation on modern Excel:

    1. In Excel, go to File > Options > Trust Center > Trust Center Settings > ActiveX Settings.
    2. Select "Prompt me before enabling all controls with minimal restrictions".
    3. Restart Excel once to apply the preference.

    (Why this helps: If Microsoft 365 has ActiveX set to silent blocking, Excel may display a yellow bar or a module compile notice when opening interactive tools. This quick one-time setting ensures all forms and drop-downs initialize instantly.)

  7. Important Note: Drop-down lists are used throughout the workbook. Cells with drop-down lists do not support manual entry of new values. The drop-down lists are bound to tables. New values must be added via the respective lookup table. For example, the 3 right-hand columns in the Equipment table (EQPT Type, Area, and Process) have drop-down lists. New values, not already present within the drop-down lists, must be added via the respective table (EQPT Types, EQPT Areas, or Processes) as shown in the next step. Cells without drop-down lists support manual edits and new values.
  8. Define Site, Process, and Equipment Specific Information.
    View and edit this information within the Lookup Tables worksheet. Data within the Lookup Tables worksheet may be directly edited. Important Note: Rows may be added by right-clicking on a table cell and choosing Insert->Table Rows Above. Rows may be deleted by selecting a range of rows, right-clicking and choosing Delete->Table Rows. Edits performed within the Lookup Tables worksheet are cascaded to the Master Question Table worksheet. Note: Table columns must not be deleted. Table structures and column headings must not be changed as this will break the underlying VBA automation code.
    1. Define the site Areas:
      Defining plant site areas in the PHA Excel lookup table
    2. Define the Processes:
      List of manufacturing processes defined in the PHA spreadsheet
    3. Define the Equipment Types:
      Equipment types configuration table in the What-If PHA tool
    4. Define the Equipment Tags and associate them with their respective Equipment Types, Areas, and Processes. You may freely enter whatever data you would like for the Equipment Tag No. The Equipment Type, Area, and Process entries untilize drop-down lists that reflect the data of their respective tables.
      Master Equipment List showing Tags, Types, and Areas in Excel
    5. Easily import the above information from steps 1 thru 4 via the "Import Equipment" button shown in the previous Step 4. The Import Equipment screen allows a range of 4 columns containing: Tag No, EQPT Type, Area, and Process to be copied from another spreadsheet. Clicking the "Import Equipment" button displays the following screen:
      Import Equipment pop-up form for bulk data entry in the PHA tool
  9. Review What-If Question Information.
    The What-If PHA Spreadsheet is pre-loaded with 100+ sample questions for the chemical and process industries.
    1. Review Question Categories:
      Reviewing What-If PHA Question Categories
    2. Review Master Question List::
      Master list of What-If PHA questions and associated categories
    3. Easily import the above information from steps 1 thru 2 via the "Import Questions" button shown in the previous Step 1. The Import Questions screen allows a range of 3 columns containing: Sequence, Question, and Question Category to be copied from another spreadsheet. Clicking the "Import Questions" button displays the following screen::
      Interface for importing custom Process Hazard Analysis questions
    4. Assign questions to specific Equipment Types:
      Linking specific equipment types to PHA questions in Excel
  10. Review/Customize Risk Matrix and Associated Charts.
    1. The Default Risk Assessment Matrix is 5x5, and it may be customized for different dimensions and matrix values. This chart is purely informational and may be edited without concern for rendering worksheet logic inoperative. It is located in the Matrix worksheet and appears as follows:
      Customizable 5x5 Risk Assessment Matrix in the What-If PHA Spreadsheet
    2. A Risk Likelihood Definitions sample chart is located in the Matrix worksheet. This chart is purely informational and may be edited without concern for rendering worksheet logic inoperative:
      Risk Likelihood Definitions reference chart
    3. Sample Severity meanings are displayed in this chart located in the Matrix worksheet. This chart is purely informational and may be edited without concern for rendering worksheet logic inoperative:
      Risk Severity and Consequence definitions chart
    4. A sample chart of Risk Assessment values and their meanings is located in the Matrix worksheet as shown below. The following chart may be edited to fit your What-If model; however, Excel Named Ranges are defined on the cells in the Assessment Values column and these Named Ranges are referenced within the formula for Risk calculation located in the Risk cell of the hidden "Template" worksheet. You may modify the text within the Meaning or Accountable Organizations columns without concern for rendering worksheet logic inoperative:
      Risk Assessment Values and Meaning table for risk calculation
    5. When editing the Risk Matrix dimensions and values, it may be necessary to update the formula and the dynamic color formatting for the Risk cell in the hidden Template worksheet. The dynamic color coding of the Risk cell is achieved through conditional formatting as shown in the following sample from the Matrix sheet:
      Excel Conditional Formatting rules for dynamic risk coloring
  11. Filter, Select, and Copy Questions to a New or Existing What-If.
    1. The Select Questions sheet has a filter mechanism whereby the user may choose "ALL" or specific Question Categories and EQPT Types. Choose the filter conditions and click the Apply Filter button to display the matching Questions. Mark the Sel column checkbox for desired Questions and click the Copy To button. A sample from the Select Questions sheet is shown below:
      Filtering and selecting questions to copy into a new PHA study
    2. A Copy Questions screen is triggered by the previous step when the user selected Questions and clicked the Copy To button. Now, the user may choose an Existing or New What-If Name and an EQPT Tag for which to apply the previously selected questions. Selecting an EQPT Tag is simplified by filters for Area, Process, and EQPT Type. After locating the desired EQPT Tag, the user clicks to highlight it and then clicks OK to finalize the copy process. A sample Copy Questions screen is shown below: Assigning selected questions to an equipment tag for a new What-If scenario
    3. After choosing OK in the previous step, a What-If worksheet is created or updated as shown below: Completed What-If PHA Worksheet in Excel showing scenarios, safeguards, and recommendations
    4. Risk Matrix value dropdown lists and formulas are automatically inserted into the Severity, Likelihood, and Risk columns as shown below: Using automated dropdown lists to select risk severity and likelihood
  12. How to Customize the Risk Matrix

What-If PHA Resources

  • Version 2.0 Architecture: Re-engineered for full compatibility and security resilience with modern Microsoft 365, Excel 2024/2021/2019, and Windows 11.
  • Increase your PHA study productivity with our automated spreadsheet and the included PHA resources.
  • Provides a structured, systematic framework to assist qualified PHA teams in organizing and documenting process hazard evaluations.


What-If PHA Automated
Spreadsheet

Guidelines for PHA

Ammonia Refrigeration
PHA Question Set