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On the subject of SNIFFER calculations, has anyone else noticed the discrepancy in the way soil organic matter is used in the calculations of inhalation pathways for organics? In the SNIFFER V1.02 spreadsheet the user is prompted to input SOM (%) in cell G281. In the next cell (G282) the user is prompted to input mass fraction of organic carbon in soil, foc. This value is then divided by 167 and the result appears in the blue cell I282 with units of kgOC/kgsoil. The problem is that foc is already in these units. It is the value of SOM in % that should be divided by 167 to give foc. You can see this if you refer to the printed worksheet in LQ01, on page 144, where the user is prompted to input SOM (%) into box 53 and this is divided by 167 to give box 53. You can see this in the worked example in the same document. The values in box 53 and cell I282 are used in the calculation of SF. Cell G281 is not actually used anywhere. My interpretation is that the paper version is correct and the spreadsheet version is not. The result of this is that if you use the spreadsheet and input foc into G282 you will derive an SSAC that is too low, by up to 2 orders of magnitude depending on the contribution from that pathway. In order to get the correct result, you should enter SOM (%) again into G282. I have checked this by entering the worked example into the spreadsheet, I get the same SSAC when I enter "2" into this cell, not 0.012. Regards, Kevin Privett. Dr Kevin Privett Principal Geo-Environmental Consultant Hydrock Consultants Ltd Over Court Barns Over Lane Almondsbury Bristol BS32 4DF Tel: (01454) 619533 Fax: (01454) 614125 [log in to unmask] <mailto:[log in to unmask]> Cell phone: (07799) 430870 Offices in Bristol, Plymouth, Northampton, Stoke-on-Trent. www.hydrock.com Disclaimer The information in this e-mail is confidential and may be read, copied or used only by the intended recipients. If you are not the intended recipient you are hereby notified that any perusal, use, distribution, copying or disclosure is strictly prohibited. If you have received this e-mail in error please advise us immediately by return e-mail at [log in to unmask] and delete the e-mail document without making a copy. Whilst every effort has been made to ensure this email is virus free, no responsibility is accepted for loss or damage arising from viruses or changes made to this message after it was sent.