EFHSS Questions and Answers - Answer to Question Q00575

For the last month i have had a lot of wet loads coming out, the steam quality tests were done and i had a dryness fraction of 0.91 and i have changed all the steam traps on the plant and cant seem to alter the dryness fraction to 0.95 but preferably to 0.97 can anyone help as i am pulling my hair out over this, and has anyone else had these problems and what was the solution

Andrew.

Dont pull your hair! Not in the CSSD!
An autoclave does not produce water. Check the steam source. Start from the water supply. This may be your major problem. The minor one is to check the vacuum system. Start from the discharge pipes. May be they are clogged of scale?
Could it be that the packaging is not an appropriate type?

miki

Andrew,

There are a couple of things that you can check in an attempt to bring the wetness factor to 0.95%.
Mikki is correct in stating that the problem is related to the boiler

1. 1. Check the temperature of the feedwater. It should not be less than 80oC.
   Rational: If you have a saucepan of boiling water and pour a mug of cold water into it, it will stop boiling until it can "recover" and start to boil again at 100oC.
   If you are running your sterilisers at peak levels and cold water is netering the boiler from the feedwater tank, then you will have water being drawn into the steam distribution system and subsequently into the steriliser.s the boiler a multi use system? If the answer is yes, then other people drawing off steam at peak trimes could affect the steam quality and also generate your problem. So check the time factors when the problems are most prevelant.
2. 2.You mentioned that new traps have been installed. Are they correct type? Ideally a ball and float trap is better suited for sterilisers as they do not require a pre-determined temperature to be reached before they become activated.
3. 3.There should also be steam dryer (separator) on the downside of the steam system adjacent to the boiler. There should also be a steam dryer on the upstream side of the distribution system just before it enters the pressure reducing valve and enters the chamber.
4. 4.Check with the hospital engineer to see if the boiler is running at its efficiency rating. Often, in an attempt to save money on energy, engineers may reduce the efficiency rating of the boiler which will then result in wet steam.
5. 5. If all else fails, contact Spirax Sarco who are experts in this field.

Hope my suggestions assist you .
Kind regards
Bill Davis
gke Australia

thanks for the info lads but ive tried all of these and also various traps but still wet loads, the only other thing ive noticed is that the air con at this time of the year is a lot colder in the pack so i have noticed that the tins are ice cold so we are leaving the tins in the machine before starting for 5 mins, this has helped a little but im still getting wet loads on heavy tins, the weight of the tins are 9.5 kg, if you have any other ideas it would be greatly appreciated.

cheers
andy hough.

Andrew,

The sheer weight mass of the metal tins ar 9.5kg would generate an enormous amount of condensate and if this is contained in a single pack then the volume of condensate would be almost impossible to "flash off" during the exhaust phase of the cycle orthopeadic trays of similar weight create the same problem. Tray liners or any other absorbant material may help but I suspect that you may have already have tried these.
We actually have a video where you can see the amount of condensate generated from a 150mm ball supported on a frame over a beaker graded in mm. 600mm of condensate is created and 30% of this condensate is left on completion of the cycle, so your tins at 9.5kg would generate an enormous amount of condensate and the energy required to flash it off is just not available.

Regards
Bill Davis
gke Australia

To all who would like additional/general information to the "Wet load" problem.
Queensland Health Infection Control Gov. published a list presenting the most common possible causes of wet packs in steam sterilization with actions suggested for each situation.
Look for Appendix G: Wet packs: troubleshooting.
www.health.qld.gov.au/infectioncontrol/documents/pdf/APPENDIX G.pdf
Or search with the keyword "Queensland Health Infection Control Guidelines." or just "Wet packs".

With dry load wishes
Josy Holdener