FAQs for Phast™ and Safeti

Phast and Safeti are available in English, Spanish and Chinese.

General requirements 

Operating system: 64 bit Windows 8.1, 64 bit Windows 10 or 64 bit Windows 11 or later versions with latest Windows Updates and Windows Security patches. 
Display: 1024x768 resolution or higher, 1920x1080 (recommended) 
Video card: Any good video card and screen supporting 1920x1080 with latest video driver installed. For Safeti, any CUDA 11 compatible video card recommended with “compute capability 5.0” or higher. See here for more information. 
Microsoft Excel: required only if using the Excel import/export functionality 

Citrix, Microsoft Hyper-V, Oracle VirtualBox, VMware virtualisation tools are not supported. 

Phast requirements 
Typical use case: Modelling a small number of scenarios per study (e.g. vent dispersion, emergency scenario modelling, etc)
Requirements: 2 GB RAM, Intel i5 or better CPU with 2 or more cores, 5 GB free hard disk space 

Typical use case: Modelling a large number of scenarios per study (e.g. as input to QRA, FERA, etc)
Requirements: 8 GB RAM, Intel i5 or better CPU with 4 or more cores, 10 GB free hard disk space 

Typical use case: Running CFD calculations
Requirements: 32-64 GB RAM, Intel i9 or better with 8 or more cores, 50 GB free hard disk space 

Safeti requirements 
Typical use case: Performing QRA/FERA for small/medium size sites such as LNG terminals gas terminals
Requirements: 8-32 GB RAM, Intel i7 or better with 4 or more cores, 50 GB free hard disk space 

Typical use case: Performing QRA/FERA for large sites such as refineries or multiple pipelines
Requirements: 32-64 GB RAM, Intel i9 or better with 8 or more cores, 100 GB free hard disk space 

Comments on RAM
Phast and Safeti can use significant amounts of memory especially for large studies. Having more memory reduces the possibility of reaching physical memory as the number of scenarios in your study grows. If you reach physical memory limits you will most likely see slower run times and could see run-time failures.

Comments on hard disk
Phast and Safeti makes a lot of use of the hard disk for storing temporary files when loading, saving and running calculations. There are two main considerations: 

• Speed: An SSD disk (Serial Solid-State disk) is recommended to ensure that read\write times do not cause run-time performance issues. A disk using M.2 NVMe instead of SATA interface would improve the read/write times.
• Capacity: It is good practice to keep 25% of disk space free. It is important to monitor the state of your hard drive and delete temporary files regularly.

The user interface is built using C# WPF targeting .NET Framework 4.8. Risk Results are stored using Microsoft SQL Server. The calculation models are mainly developed in C++ or Fortran.

Yes, DNV offers a wide range of training courses, available here.

All versions of Phast and Safeti can be downloaded via our Knowledge Centre.

The Knowledge Centre also provides release notes, detailing updates to each version.

Details of upcoming events and webinars can be found here. Recordings of past webinars can be found here.

In the context of consequence modelling, a free-field is an open environment without any obstacles or undulating terrain to affect dispersion, fires or explosions. Consequence calculations in this environment are simpler than those where obstacles or undulating terrain need to be taken into account. The duration of a free-field modelling calculation for a single scenario will typically be of the order seconds. 

Where it is important to consider obstacles or undulating terrain, computational fluid dynamics (CFD) is the preferred solution. The duration of the calculations, being significantly more complex, will typically be of the order minutes to hours..

A QRA is a numerical method for predicting the consequences and risk associated with hazardous facilities or operations. More details are provided in this webinar.

Our QRA solutions focus on fatality risk (individual and societal). Our QRA software produces metrics which can also be used to assess environmental risk, asset risk and financial risk.

Phast/Safeti is used typically in the following industries:

• Academia
• Chemical processing
• CO2
• Energy
• Hydrogen
• Insurance
• LNG
• Oil and gas
• Petrochemical
• Pharmaceutical
• Public sector (governmental and regulatory bodies)
• Transportation and storage

Phast/Safeti is used typically for the following asset types:

• Chemical plants
• Gas terminals
• LNG terminals
• Offshore installations
• Petrol stations
• Pipelines
• Refineries
• Storage facilities (e.g. tanks)
• Transportation assets (ships, tankers, trucks)

Our consequence and risk analysis solutions can be used in all stages of an asset's lifecycle. Often, the earlier consequences and risks are understood, the more valuable the insights prove to be.

Phast is typically used in the following applications:

• ALARP demonstration
• Consequence estimation for HAZOP, HAZID, PHA, LOPA
• Consequence input to your own QRA tool
• Emergency response planning
• Equipment design
• Escalation assessment
• Extent and severity assessment
• Facility siting and layout optimisation
• Hazardous area classification
• Regulatory obligations (e.g. safety reports)
• Vent and flare design
• Other general consequence estimation

In addition to having the applications of Phast, Safeti is typically used in the following applications: 

• Cost-benefit analysis 
• Fire and explosion risk assessment (FERA) 
• Occupied buildings risk assessment (OBRA) 
• Quantitative risk analysis (QRA) 
• Risk-based design
• Sensitivity analysis

Phast is consequence modelling software, whereas Safeti is consequence and risk modelling software. 

Phast/Safeti calculates the discharge, dispersion and flammable and toxic effects associated with loss of containment scenarios. It can be used to model pool spreading and evaporation, fires (jet, pool and fireballs), explosions, BLEVE and toxic effects.

For pressure vessels, Phast/Safeti is able to model instantaneous releases (e.g. catastrophic rupture) and continuous releases (e.g. leaks from pipework). For continuous releases, Phast/Safeti can model constant or time-varying release rates, fixed duration releases, short pipe releases (line rupture, disc rupture and relief valve). Further, Phast/Safeti has a user-defined source, giving full control for the users to define the source terms.

In addition to the above, Phast/Safeti can model spills from atmospheric tanks and vent releases from the vapor space.

The Multi-Component extension allows consequence modelling of hazardous multi-component two-phase releases into the atmosphere. To find out more about DNV's approach on two-phase multicomponent modelling, refer to "Modelling the Consequences of Hazardous Multi-Component Two-Phase Releases to the Atmosphere", H. Witlox, M. Harper et al (2005).

Yes, Phast and Safeti can model toxic releases, including modelling of asphyxiation. DNV's Unified Dispersion Model (UDM) is used to determine the dispersion of a toxic material (or in the case of asphyxiation, any inert gas that reduces or displaces the oxygen concentration) over time, which will be used to determine the concentration of a material at a specific location in a given time.

Yes, Phast has the capability to model hydrogen, carbon dioxide, nitrogen and ammonia releases.

Yes, Phast/Safeti can model LNG and LPG releases.

Phast/Safeti can model "in-building" releases, where the build-up of concentration indoors and subsequent dispersion outdoors is modelled. Explosion effects inside the building are also presented.

Testing of the software includes: 1) Verification of the consequence models to ensure that the code correctly solves the associated mathematical model, 2) Validation of the results against experimental data, and 3) Sensitivity analysis by varying a large number of parameters to ensure overall robustness of the code.

DNV has produced a document which describes the verification and validation process for the modelling of flammable and toxic releases. This can be made available upon request.

Phast and Safeti support import of shape files from Google Earth or other GIS. Consequence and risk contours can be exported shapefile (*.shp) for import into Google Earth or other GIS. Our product videos catalog has instructions for getting the most from Phast and Safeti's GIS. 

We offer a range of lease / subscription options from 1-day up to 3 years as well as perpetual. Lease / subscription options are available to purchase digitally using credit card or invoicing via our Veracity marketplace.

Lease / subscription and perpetual options are also available by speaking to a sales manager.

We offer the following types of licence: 

• Standalone: the licence file is located on a specific PC. Only that PC can operate the software.
• Dongle: the licence file is provided on a USB stick. The software can be installed and used on any PC where the USB dongle is plugged in.
• Network (local, regional, global): the licence file is located on a network server. PCs located on the same network can operate the software, depending on limits to the number of concurrent users.

Phast/Safeti can be installed on your own PC or can be pre-installed on a virtual machine. Please go to our Veracity marketplace for more details.

It is not possible to transfer an individual Phast license from one machine to another. We have other licence types (dongle and network) which support multiple users in an organization.

Phast version 8.4 is approved by the Pipeline and Hazardous Materials Safety Administration (PHMSA) in the United States, while Safeti NL is the official software used by the National Institute for Public Health and the Environment (RIVM) in the Netherlands. 

Phast and Safeti software is widely accepted by regulators from various countries such as Netherlands, UK, Australia, Singapore, Malaysia, Hong Kong SAR (China), and many more.

It is possible to carry out simulations in three dimensions (3D) using the Phast CFD capabilities (powered by KFX) in Phast. However, to account for the impact of three-dimensional geometries and terrains to the release scenario, it is recommended to consider the Phast CFD add-ons (such as Phast CFD – jet fire, Phast CFD – pool fire, and Phast CFD – dispersion) that are available. Future versions will include new CFD add-ons.

The training for Phast and Safeti software is extensive and global. You can learn more here.

Over 10,000 users have been trained worldwide, with around 1,000 new users trained yearly. Regular training seminars, user conferences, and workshops are conducted in various locations around the world.

Global technical support is provided from various hubs covering all time zones. Additionally, rich help resources, including built-in help, technical documents, and product videos are available within the Knowledge Centre.

Phast is used by more than 1,000 organizations across various industries, and it has been extensively validated over the past 40+ years. Case studies and validation documents can be found in the technical documentation provided with Phast, or through the Technical Documentation section in the Knowledge Centre.

Users have the option to access Phast/Safeti via a pre-installed virtual machine. Additional details can be found on the Phast and Safeti Veracity pages. Alternatively, users can purchase standalone consequence modelling applications using Phast Online, our web-based modelling tool powered by Phast.

The software undergoes rigorous testing, including verification of the consequence models, validation against experimental data, and sensitivity analysis to ensure robustness. Detailed information on the verification and validation process is available through the Technical Documentation section in the Knowledge Centre. Additionally, the Phast team is actively working with DNV Spadedam and external partners on full-scale experiments for validation.