Hazard study software
Process Hazard Analysis Software
HAZOP, What-If, HAZID and LOPA on your own desktop, for macOS and Windows.
Free trial: start it in PHAx after you download it. More users, a partner deal or a special arrangement? Ask Arborion
Version 1.0.3. Create your Arborion account in PHAx and PHAx activates automatically; each computer uses one seat of your licence or trial. Sit in on a demonstration
Desktop software for HAZOP, What-If, HAZID and LOPA, where the screen is the study record
PHAx is built for the scribe and the facilitator in the room. The team's words go straight into a worksheet that behaves like a spreadsheet, ranked in your own risk matrix, with safeguards, LOPA and actions linked to the scenario they came from. Every value on the screen can be traced to a session, a person and a saved version. We chair hazard studies ourselves, and PHAx is the tool we record them in.
The screens below are PHAx itself, showing an illustrative example study that describes no real plant. One study file carries the record from node to closed action, so nothing is copied between spreadsheets.
Carries forwardnodes with their drawings and revisions
Scope, boundaries, team, sessions and attendance sit in the study. Nodes are one row each, with design intent, boundary, operating conditions, equipment and their drawings. P&IDs are imported in bulk and each node is marked on them in its own colour, and the marked-up drawings are written to the project folder as images and one combined PDF.
Carries forwardone row per scenario, ranked before and after safeguards
A flat grid with one row per scenario. The deviation and the cause are written once and merged down over their rows, so the sheet reads the way the team talked it through. Type in the cell, split a cell into more deviations, causes or consequences, and put several safeguards or recommendations in one cell, one per line. Columns can be added, renamed, reordered or hidden per method.
Carries forwardthe company's own risk levels and required actions
The risk matrix is yours: any size, your severity and likelihood levels, frequency bands, consequence categories, colours and required actions, with risk found by cell lookup or by score. Each scenario is ranked before and after safeguards. The shipped matrix is marked as an example, and PHAx keeps flagging it until the company matrix replaces it.
Carries forwardSG numbers, IPL claims and verification
Every unique safeguard is held once, as SG‑###, with the scenarios it is credited on and whether it is claimed as an independent protection layer with a PFD. Safeguards are verified rather than owned: verified or failed, by whom, on what date and how, for one safeguard or many at once.
Carries forwardIEL, required PFD, RRF and SIL band
Send to LOPA turns the selected scenarios into LOPA rows and carries their claimed layers across. Enabling conditions, conditional modifiers and protection layers sit under heading bands, each with its value and description. PHAx works out the intermediate event likelihood, the target, the required PFD, the risk reduction factor and the SIL band. A layer is credited only when it is independent, specific and auditable and has a PFD.
Carries forwardREC numbers, owners, due dates and history
Anything written in a Recommendations cell lands in one register with a permanent REC‑### number and its scenario references. Each action has an owner, a due date, a stage from not issued to closed, the owner's response and evidence, verification and a full history. Actions can be issued, extended and closed inside PHAx or through Microsoft Power Automate.
The risk profile plots every scenario three times: inherent, with the existing safeguards, and after the recommended actions. A row with an action but no residual ranking is shown as a gap, never guessed.
Every risk cell is a lookup on the study's risk matrix, S and L cells have dropdowns from the matrix, and the LOPA sheet keeps its IEL, required PFD and RRF as live formulas. Change a value in Excel and the risk follows.
Introduction, methodology, risk matrix, team and attendance, recommendations, LOPA and assumptions, with the worksheets and the open gaps as appendices. Cell formatting is carried across.
Loss of containment scenarios exported in CSV or JSON with permanent SCN references. Release size, inventory, conditions and weather are listed as data gaps for the QRA, never filled in by the software.
The QA register lists missing data, inconsistencies and rules that are not met while the study is recorded: an example risk matrix still in use, a severity above the LOPA threshold with no LOPA, an IPL that is claimed but not verified. Double-click a finding to go to it.
A ribbon, in-cell editing, a formula bar, cut, copy and paste of rows, fill down, filters, zoom and full screen. Commands grey out when they do not apply.
Import drawings in bulk as PDF or images and mark each node's extent with a highlighter, a box or a tag in the node's colour.
Right-click any cell to put an open question in the parking lot. The cell keeps a marker until the item is closed.
HAZOP, LOPA, blowdown and knock-out are words, and tags, acronyms and numbers are left alone. UK and US spelling are both accepted.
One click writes H₂S, m³/h and 1×10⁻⁴ in the selected cells, in a form that looks the same in Excel and Word.
Issue actions, approve extensions and closure, and submit the study for review, in PHAx or through Microsoft Power Automate. The dashboard shows every study and action on the site.
Every awkwardness in the recording model was found by our own leaders and scribes in live sessions, not in a specification workshop. When a field slows a study down it gets changed, because we are the ones sitting in the room when it does.
Values the team has not given, such as an initiating event frequency, a PFD, a target or a missing ranking, stay blank and appear as gaps. Typical LOPA values are offered as a pick-list with their source written into the record, to be verified against the company register.
Saves are atomic and keep a backup. Every save adds to a hash-chained history, so an edit made outside PHAx is detected when the study is opened. Revisions can be issued frozen and compared with the current record, and each day's work can be kept in its own dated file.
PHAx records and structures a hazard study. It does not chair one. The quality of a study still rests on an independent competent leader, accurate drawings and a team willing to disagree with the design, and no software changes that.
Download PHAx for your computer and start a free trial in the app, or sign in with your Arborion account to buy a licence. We can also chair the study and scribe it in PHAx for you. Arrange a session
Free trial: start it in PHAx after you download it. More users, a partner deal or a special arrangement? Ask Arborion
Using PHAx is subject to the PHAx Terms of Use and the PHAx Privacy Statement. Cancellations are refunded pro rata under the Refund and Cancellation Policy. Your studies stay on your own computers. Licences, trials and support: support@arborionglobal.com.