SevaluateTM is an Excel based program which runs your COMAH (Seveso III) calculations for you, provides printable reports showing the main contributors to your COMAH liability, and allows you to predict the impact of changing your COMAH inventory on your COMAH liability.

It’s ideal for demonstrating your COMAH status to the HSE, particularly for sites with a large product and/or raw material range, or an inventory which changes frequently.  SevaluateTM is particularly useful for sites controlling their inventory to keep out of COMAH, or stay within Lower Tier.

SevaluateTM is installed on your own laptop or workstation, under your control, so you don’t need to worry about sensitive commercial information being “in the cloud”.  You own the data you input, and the output data.

How does SevaluateTM work?

SevaluateTM is easy to use because it’s based on Excel, and all of the required calculations are built into the software as formulas (no macros are used).  You only have to input some basic information, and SevaluateTM does all the hard work:

  • For each material, you enter in its name, CLP classification, (ideally CAS and/or EC number for substances), package size, a conversion factor to  ensure the mass of material is expressed in kgs, and quantity of the package.  You can copy information across from another Excel file, for example from your stock control system.
  • SevaluateTM automatically assigns materials to Named Substance categories, and highlights where information requires manual  input to enable the software to make a decision. It also highlights where extra information can be input, as not all of the Named Substances can be identified on the basis of the original inputs.
  • For materials which are not Named Substances, SevaluateTM assigns these to physical, health environmental and “other” categories. Like Named Substances, these materials may require manual input of extra information, which SevaluateTM highlights for you.  There are also some physical hazard categories which cannot be identified on the basis of the original inputs, and SevaluateTM highlights where this information can be entered into the software voluntarily.
  • There is a review page enabling you to check and amend all of the input information, and SevaluateTM automatically calculates COMAH liability based on the information on this page.
  • A series of reports are automatically generated for you, showing whether the site is within COMAH scope, whether it is Lower Tier or Upper Tier, and for what reasons (eg Lower Tier for Named Substances, or Upper Tier for Physical Hazards); the main inventory contributors to COMAH liability; and detailed contributors to COMAH liability by each category, that is Named Substances, all of the individual physical hazards (P1a to P8), health hazards (H1 to H3), environmental hazards (E1 and E2) and other  hazards (O1, O2 and O3) . The SevaluateTM reports can be viewed on-screen, printed, or converted to pdf (if you have the facility).

How long does it take to run SevaluateTM?

SevaluateTM itself can run quickly, once you have all of the relevant information available.  If you can import material information from Excel, the process can be very quick.  In-house, it has taken us around fifteen minutes to generate a COMAH liability result based on 509 materials; and  around half an hour for a result based on 1844 materials. The time taken tends to depend on the amount of information SevaluateTM asks you to input manually after you have copied across the main material information, which depends on the type of materials in your inventory.

At the time of writing, the main time input can be finding CLP classifications for your materials to input into SevaluateTM, as many companies may still only have CHIP classification information for existing products in their inventory.  Our users find that obtaining the CLP classifications can be the longest task when using SevaluateTM , but you would need to obtain these even if you were making the calculations manually.

What are the benefits of using SevaluateTM?

Using SevaluateTM puts you in control of your COMAH liability status.

You can use it to track your COMAH-liable inventory, and it can easily be kept up to date by inputting changes in your inventory information, or to hazard classifications.

It can help you control your inventory to stay below Upper Tier limits, or below Lower Tier limits, which would keep your site out of COMAH altogether.

SevaluateTM also provides information which needs to be reported to the HSE if your site does come under COMAH scope.

It works on your own computer, not in the cloud, so your confidential inventory information is kept in-house.

You don’t need to rely on external consultants for the answers you need.

What are the alternatives to using SevaluateTM?

At the moment, choice is limited to making your own spreadsheets up, based on the COMAH regulation requirements; using an external consultant; or using the bespoke services of the Health and Safety Laboratory.  Some companies have also put COMAH information into their stock management systems, with help from their IT or software specialists, although the quality of these one-off systems can be variable, in our experience.

Who would find SevaluateTM useful?

It is used by HSE managers and directors in the chemical industry, and could also be used by onshore oil and gas sites, hazardous waste sites, food industry, chemical warehouse managers, or consultants helping high hazard sites.

You can use SevaluateTM to run your COMAH liability calculations occasionally, or to check your COMAH liability regularly, to ensure you don’t breach the Lower or Upper Tier limit. SevaluateTM can also be used to check the answers from a COMAH liability calculation system which is part of your Stock Control system.

Can SevaluateTM link into our Stock Control system?

At the moment (October 2017), SevaluateTM is a stand-alone system, but like any Excel based product, has the potential to link to other spreadsheets and databases.  If you are interested in this option, we would be happy to work with you and your IT team to develop this facility.

What guidance and support is there for using SevaluateTM?

There is a quick-start guide, to get you using the product quickly, and your subscription to SevaluateTM includes a detailed User Manual, to help you maximise the accuracy of the results from the programme. Like all calculation programmes, SevaluateTM is only as accurate as the information you put into it.

The User Manual is a step-by-step guide, with hints and tips on ensuring that your input information is as accurate as possible.  It comprises 34 pages, backed up with a further 112 pages of appendices, and is currently version 1.4, 21st June 2017, size 1.78 MB.

You can also email us for help, and we will email or call you back.  You can send your copy of SevaluateTM through to us for help, if there’s a problem we can’t resolve any other way, and if you do this, your information is covered by our client confidentiality policy (see our Ts and Cs here ).

Are there any quirks to SevaluateTM?

There may be a couple of quirks in SevaluateTM due to it being based on Excel, but overall it works as a normal Excel file, with pages that can be printed or pdf’d.  You can copy data into or out of SevaluateTM like a normal Excel file. However, there is security on the file to ensure that the calculation formulas/ algorithms are protected.

Can I use SevaluateTM for more than one site?

We are happy for you to use SevaluateTM for two sites on a normal subscription.  If you need to calculate COMAH liability for more than two sites, please contact us for a quotation.  (We need to charge more to cover support costs).

If you are using SevaluateTM for more than one site, we strongly recommend that you use individual copies for each site, and do not try to use the same copy of SevaluateTM for more than one site, as this is highly likely to lead to errors and an inaccurate result.

Can you set up SevaluateTM for us, and then we can run it in-house?

If you are busy, or unsure about setting up SevaluateTM correctly, we would be happy input all of your products and ensure that they are classified correctly for COMAH, then hand over the file to you to amend your inventory information, or add in new products.  This is an extra service, and therefore chargeable.

Why develop a product like this?

At TT Environmental, we have been involved in COMAH liability calculations for over 12 years, and know how important it is to understand where your site is in relation to COMAH. SevaluateTM is a product we initially developed to use on behalf of our customers, and we think that many actual or potentially COMAH liable sites will find it useful.

How much does SevaluateTM cost?

SevaluateTM is available as an annual subscription, which comes with full technical support on installation and running the software to generate a COMAH liability result for the whole year.  This includes a licence to download the software, and register and use up to two copies on one or two individual computers or other devices.  The price is £999 plus VAT per annum.

The Product Specification Sheet can be downloaded here: SevaluateTM Product Specification Sheet v1.1 17-10-2017 .

To purchase SevaluateTM, email us on with your full name, work email and telephone number, a valid Purchase Order number, and the full name, work email and telephone number of the main user (if you’re ordering ).

We will send you an email containing SevaluateTM’s End User Licence Agreement (EULA), which you must confirm your company accepts, before we can issue an invoice (we also require a Purchase Order number).  A copy of the EULA can be downloaded here: Sevaluate EULA 21-06-2017 .

Payment is required before the software can be sent out, so please let us know if you would prefer to pay by Bank Transfer, or Credit Card (please ring 01422 242222 to pay by card).

We reserve the right to decline a sale to individuals, as we are a business-to-business company.

For companies who need to calculate COMAH liability for more than two sites, please email us for a quote, including your work email and telephone number, and the number of sites you need to calculate liability for.

SevaluateTM Services

If you are under time pressure, our Sevaluate Services may be of interest:

  • Help with classifying products for CLP, either for you, or help train you in how to classify the products
  • Inputting data into SevaluateTM on your behalf, including classifying products for CLP where this information does not exist, then handing over the pre-filled package to you, so all you need to do is keep your inventory information up to date
  • Run SevaluateTM on your behalf completely, all you need to do is send through your inventory information to us on a pre-arranged schedule, and we will send you the full reports back within 48 hours

SevaluateTM Services costs vary depending on the work required, please email us on for a quote.

SevaluateTM online demo

You can book a free 20-minute online demonstration of SevaluateTM here:

Thank you very much for your interest in SevaluateTM, please get in touch on  or call us on 01422 24 22 22 if you have any queries.