DHI PHA Node Tree Builder
Build the process as numbered nodes. Piping, tanks, pumps, valves, sources, outlets, and treatment equipment are all nodes. A predecessor can be the process start, a named source, or another node. If multiple downstream nodes use the same predecessor, the predecessor automatically shows multiple named outlet branches.
Use note: This is a structured PHA/PSSR planning aid. It does not replace a formal facilitated PHA. Use it to build the process tree, capture node-specific hazards, score risk, identify administrative vs engineered controls, and create PSSR punch items.
1. Job Information
2. Process Nodes and Tree Construction
Build this like a process map. Every physical item or stream segment can be a node: source, riser, pipe, pump, tank, outlet, DAF, sludge handling, etc. For each downstream node, select the predecessor and name the outlet/stream coming from that predecessor.
3. Process Tree View
Outlet branches are automatically created by the downstream nodes. If CT-001 has three downstream nodes and each names a different incoming stream — good water, oil, sludge — CT-001 will show three outlets.
4. Connection / Outlet Register
This table is generated from the node predecessors. It is the audit list for what each node receives and what each predecessor sends out.
| Downstream Node | Node Type | Predecessor | Predecessor Outlet / Incoming Stream | Stream Material | Downstream Description | Connection Status |
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5. PHA Nodes and Risk Assessments
6. PSSR Punch List
Generate the PSSR list after the process tree and node risks are complete. Items are created from standard startup checks, unresolved connection issues, high-risk safeguards, engineered controls, and open recommendations.
| # | Category | Node | PSSR Punch Item | Owner | Due Date | Status | Action |
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7. Browser Saves
Browser saves stay on this computer/browser. Export JSON is the proper file record for sharing or archiving by job name and save date.
| Saved Job | Saved Date | Nodes | Risk Rows | Actions |
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