Welcome Guest! The IOSH forums are a free resource to both members and non-members. Login or register to use them

Postings made by forum users are personal opinions. IOSH is not responsible for the content or accuracy of any of the information contained in forum postings. Please carefully consider any advice you receive.

Notification

Icon
Error
Multigas Monitor
Options
Go to last post Go to first unread
Previous Topic Next Topic
selvinjoe  
#1 Posted : 21 July 2014 09:52:39(UTC)
Rank: New forum user
selvinjoe
Hi ,

Today morning I was asked by the Area authority (Water Injection plant) to do Gas testing in their Sea water intake tank. Upon introduction of probe into the space above water level the Gas monitor started showing changing levels of Carbon monoxide ( no constant reading). I tested the space with the second Gas monitor. Same thing happened. Both Gas monitors are calibrated. It looked strange to me.I thought some thing interfering with the CO sensors. (No chance for CO inside, the top manhole is covered by a strong metal frame with lot of holes). Could any one tell me the possible reasons for this ?
Back to top
PIKEMAN  
#2 Posted : 21 July 2014 10:40:25(UTC)
Rank: Super forum user
PIKEMAN
If two different instruments are showng it, may be it is real? What are the values displayed? ie is this in the normal range expected or not? Is this Co or CO2 you are talking about? Is there a possibility of something else interfering with the reading? If you have access to labs ask them - or call the manufacturer of the instrument. Don't ignore the reading because it seems daft - find out why this is so. CO is dangerous stuff.
Back to top
selvinjoe  
#3 Posted : 21 July 2014 11:12:01(UTC)
Rank: New forum user
selvinjoe
O2, H2S, LEL all were normal. But CO (Carbon monoxide) above 250 ppm and changing. There was no apparent source of CO.I suspect something interfering with the sensor.
Back to top
leadbelly  
#4 Posted : 21 July 2014 12:01:01(UTC)
Rank: Super forum user
leadbelly
See this: http://www.google.co.uk/...198958,d.ZGU&cad=rja as an example of the cross-sensitivity that can happen.

LB
Back to top
PIKEMAN  
#5 Posted : 21 July 2014 12:56:17(UTC)
Rank: Super forum user
PIKEMAN
Hard to see where CO could get into a sea water intake tank, but it could be real. Is it near the exhaust of any combustion unit? Or any other source og gases that could interfere with the reading, or be CO? As regards normal levels <10 ppm is the norm. Does your instrument(s) show this in open air? If it is showing more, there is something wrong. >100ppm is dangerous, if you inhaled 250ppm it could be rapidly fatal.
Back to top
selvinjoe  
#6 Posted : 24 July 2014 03:46:21(UTC)
Rank: New forum user
selvinjoe
Thanks everyone.
Back to top
descarte8  
#7 Posted : 25 July 2014 11:01:00(UTC)
Rank: Super forum user
descarte8
You could take a "grab-bag" sample of air and send it more technical analysis if you are still concerned, SAL may be able to help:

http://www.salltd.co.uk/document_areas/10045#ban
Back to top
Users browsing this topic
Guest
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

Powered by YAF.NET | YAF.NET © 2003-2025, Yet Another Forum.NET