I wasn’t aware of any alternatives to using chemicals in cassette toilets until fairly recently when I got chatting to a neighbour who has been using a SOG system in his campervan.  Jack installed the SOG system is his Mercedes Sprinter conversion in 2010 after a tour of Europe where they are quite popular.

sog campervan toiletA SOG toilet negates the use of chemicals and works by drawing air into the cassette when the toilet valve is activated.  A low powered fan creates negative pressure which draws oxygen into the cassette from the bathroom of a campervan or caravan.

This system is designed to draw off any odours while using the toilet and stop any odours being emitted from the cassette.  Also, by passing air over the waste it is said that this accelerates natural composting and reduces unpleasant smells.

I carried out a little bit of research into the SOG system before deciding if it was for me, prior to purchasing a kit.  I found a number of good reviews with many campervan and caravan owners swearing by this bit of kit.

It seemed that a SOG system had many benefits over any drawbacks:


  • Saving money on chemicals
  • Vents odours from the bathroom or toilet compartment
  • Frequent emptying of cassette without worrying about wasting the chemicals stored in the cassette
  • Not having to store chemicals in your campervan
  • Normal toilet paper can be used
  • Sites in some countries ban the use of chemicals at their disposal points.  A SOG system overcomes this problem
  • Being able to flush the contents into a conventional toilet



  • Initial cost
  • No perfume to mask the smell when emptying a cassette


The benefits quite outweighed any negatives so I searched the internet and found the best price for a SOG kit.  When fitting the system I took my time to ensure that I drilled in the correct places and fitted the system correctly.  After a couple of hours my toilet was ready but as I was not due to camp for a few weeks the testing of the SOG system had to wait.

Vacation day finally arrived and we set off after the usual checks that we had everything packed (minus the toilet chemicals).  We had a six night tour of Devon staying at four different campsites and were blessed with some great weather.

We were really pleased with the SOG toilet and wished we had installed this years ago (had we known about it!).  The SOG is very effective at stopping odours coming from the waste cassette and when the bathroom door is opened we are free from the chemical smell that sometimes invades the whole campervan.

The SOG kit only cost £115 and we estimate it will have paid for itself in less than a year from the saving in buying chemicals.  We are also pleased that our impact on the environment has been reduced in not using and disposing of chemical products.

By John Hardcastle

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