ExTool V4

Business case

A client seeks cover for his large steam cracker with a name plate capacity of 680 Kt  per year. The total sum insured TSI for the whole plant is stated to be USD 351million. Unfortunately it goes unnoticed that this value would lead to a massive underinsurance of the installation.

The insurance engineer who operates ExTool V4 is asked to provide an estimation of the maximum possible loss (MPL). Modelling the installation the engineer gets suspicious about the total sum insured. Therefore, he runs a quick sanity check using the valuation routine in ExTool V4. To perform this, he just needs the name of the installation, as the geo-coordinates, the nameplate capacity and the various cost indexes for time correction are all provided within the tool. Within minutes, he estimates a total sum insured of USD 635 million. As the difference to the TSI on the slip is significant, which further results in a far too low MPL estimate, the engineer notifies the underwriter of a potential underinsurance. The insured is pleased with the benefit from the underwriter and considers contacting a specialized valuation firm to assess the TSI of the installation.

With the introduction of ExTool V4 to the insurance market, such massive underestimations of the TSI has become a thing of the past. Renewals are more effective, and basic assumptions about risk exposure have been standardized across the industry.


Explosions are often the primary cause of major incidents in the oil and petrochemical industries. These industries have a high loss potential because they process and store large amounts of flammable materials or operate under extreme processing conditions. Given the trend in the process industries towards ever larger, more complex and more integrated installations, the loss potential is constantly increasing. It is therefore in the interest of all parties concerned with risk — namely insured, insurers, reinsurers and authorities — to be able to estimate the consequences of a major explosion event.

Using TNT explosion models, ExTool offers a conceptually simple yet highly flexible and transparent means to draw up such estimates. It has proven to be particularly valuable in cases where the risk of losses from catastrophic explosion is high. ExTool simulates explosions in spaces made up of open steel structures, such as refineries and other industrial processing sites. ExTool also simulates tank fires and liquefied natural gas (LNG) spills, and it calculates flash fractions and vessel volumes. The new ExTool V4 carries on the success story of previous ExTool versions with a reputation for excellence and reliability - commensurate with what clients expect from Swiss Re.

What's new in ExTool 4.0?

ExTool V4 contains a valuation module. It allows to estimate the sum insured of whole refineries, steam crackers, some other petrochemical plants, and to escalate these values with established cost indexes such a Nelson Farrar and IHS CERA. All refineries worldwide, together with their corresponding process units, are available in the built-in database of ExTool V4. Values of each unit can be estimated based on throughput.

In short, ExTool V4 features the following significant enhancement over version 3:

•    A database of global refineries and steam crackers including process unit throughputs taken from the World Wide Refinery Survey
•    Revised geo-coordinates, including a search function for operators, locations etc.
•    Online access to Google EarthTM imagery directly from the database of locations or using user specified coordinates
•    Value estimation of most refinery units
•    Value estimation (sanity check) of whole plants, such as refineries, petrochemical plants and steam crackers
•    The ability to update unit and plant valuations using the IHS CERA Downstream and Nelson Farrar Refinery Construction cost indices, or a user defined inflation rate
•    Transparent unit block shading with or without values
•    Re-scaling of site plans at any time during an assessment
•    Improved user friendliness of flashing of mixtures module
•    Entering of data in a variety of units including SI, US, Imperial and other commonly used units


ExTool provides the user with transparent and easy-to-use models to assess damage potentials associated with vapour cloud explosions (VCE) and ruptures of high-pressure equipment (HPR). The models can either be used to estimate the strength of a VCE or an HPR. Combined with a distribution of property values from the process plant in question, it can also yield an explosion loss estimate in monetary terms.

Although explosions may have severe consequences for exposed personnel, ExTool V4 focuses on damages to property only. It provides key information in order to:

•    assess the potential strength of an explosion
•    assess the severity of a tank fire
•    estimate evaporated mass from a refrigerated hydrocarbon spill, such as an LNG spill
•    draw sites or import drawings, with a distribution of their known monetary values, or estimated by ExTool
•    determine monetary losses caused by an explosion, and extrapolate maximum possible loss (MPL) from those figures
•    visualize results in a variety of meaningful ways
•    provide flexible tools for event documentation

How ExTool works

The energy content of either a VCE or an HPR is converted into an equivalent mass of TNT. From this TNT mass, radii corresponding to certain levels of overpressure can be calculated. ExTool uses three such radii, correlating overpressure with average damage levels of 80%, 40% and 5% respectively. Finally, the circular damage areas are combined with a distribution of values for the plant in question to provide loss estimates.


A one-time fee is due for each ExTool  V4 copy. Each copy may be installed on one single machine only (desktop or laptop):

1 and 2 copies: USD 2500 per copy

3 copies: 2250 USD   per copy

4  copies: 2100 USD per copy

5 or more : 2000 USD per copy

No additional fees apply. In particular, no yearly fees will be due.

OS Requirements

Designed to operate on Microsoft Windows XP, Vista, 7, 8, 10 and Mackintosh 10.9 and 10.8.


In combination with sound risk engineering judgement, Swiss Re’s ExTool V4 offers the basic facilities for obtaining reliable and reproducible evaluations of loss potential arising from explosions. Massive underestimation sums insured will no longer go unnoticed through a renewal underwriting process anymore.


Conditions of Use, SwissRe Extool V4

1.   No warranty of any kind is made as to the appropriateness of the methods, input values or the results of the Product.  No guarantees are given that the results of any underwriting done coincidentally with the use of the Product will be profitable. 

2.   Prior to use the User shall obtain independent professional advice regarding the installation application and use of the Product in the User’s particular computer or data processing environment.  It is understood that Swiss Re shall not and will not provide any technical or software support.  The User undertakes that the Product shall only be used by persons who have been trained and are technically competent. 

3.  The User is licensed to use the Product only for its own internal purposes.  The licence is non-exclusive and non-transferable.  Swiss Re does not purport to grant any licence with respect to third party data incorporated within the Product.

4.  The Product is supplied ‘as is’ without warranty or representation of any kind, express, implied or otherwise, including without limitation, any warranty of merchantable quality or fitness for a particular purpose.

5.  In no event shall Swiss Re or its agents be liable for any special, indirect or consequential damages of any kind or any damages whatsoever resulting from loss of use, data or profits, whether or not advised or warned of the possibility of damage, and on any theory of liability, arising out of or in connection with the use or performance of the Product.

6.  Swiss Re reserves the right to adapt, alter, amend or improve the Product from time to time.

7.  Any dispute arising out of or in connection with this Product or this agreement shall be adjudicated exclusively under Swiss law and jurisdiction.

The IHS CERA Downstream Construction Cost index was provided by and is the copyright of IHS Chemical.

The Nelson Farrar Refinery Construction Cost Index was provided by and is the copyright of PennWell Corporation.