Calibration gas - carbon monoxide

[pisoiu]

I am currently working on a prototype for a 2 in 1 oxygen and carbon monoxide analyzer. I am having a hard time finding a can of calibration gas. Does anyone know where can I purchase from Europe something like this: OxyCheq - 15 PPM CO Bump Test Calibration Gas ?
I need a very small quantity in an aerosol can, with concentration around 50ppm. I was able to find suppliers in US but the shipping is ridiculous, almost $350 to ship to Romania. In Europe I was also able to find industrial solutions, with large tanks which needs regulators, etc. but this is too much for a proof of concept device. I will use those if I will start series production, but for now I need just a small spray...
Thanks.

 

[Tbar]

Hi

You may be able to use another source of gas, say car exhaust if you have a proven CO meter to analyse CO content, then calibrate your CO analyser.

I am keen to build a CO analyser. I have build the O2 analyser. Do you have a schematic for the CO, what CO senor are you using?

Thanks

 

[pisoiu]

Unfortunately I do not have another device for comparison, that's why I need gas with known content. Otherwise I was able to 'read something' just by approaching it to known sources of CO. Using random sources of CO is ok when you want to check if the sensor is responding or not, but is not a good way when you design a prototype. Souces of CO such as car exhaust may contain other pollutants at which the sensor is cross-sensitive and this will fool your readings. The only proper way of calibrating it is using a calibrating gas with known content.
I am using CO-AX from alphasense. You can see a schematic here: CN0357

 

[Akimbo]

Contact a commercial gas supplier. It will be expensive but possibly competitive with shipping from the US and a much larger quantity. Specify the mix you want, size cylinder, and they usually have the lab at their supplier mix it.

Edit: Good luck with your R&D, we need a good CO sensor. Have you considered Crowd Funding as a potential source of funds to bring it to market?

 

[pisoiu]

Such solutions are available here, we have big gas suppliers like linde, siad, etc. The problem is the cost. Not that I do not have the money, rather I am not willing to spend until absolutely necessary, and of course, I want the most 'bang for the buck'. At this moment I am trying to make a very basic prototype, just a sensor and the electronics, without case, to see how it works, etc. I do not know yet if it will be just a portable analyzer, for one gas or for multiple gases (CO, O2, helium), what case I will use, if it will be used in fixed instalations as alarm for compressors, etc. There are many variables. Analox cease the CO analyzer production for a reason, and the reason has to do with the costs. This is a niche market and if the costs are not carefully considered, I may fail before I begin. Until such decisions will be made, I need the cheapest calibration solution available, and that is a $30 spray can with bump gas, without regulators or other bells and whistles.
I have heard of crowd funding, and I will consider it when I will have a fully working prototype. The way I see it now, I will not have a problem with costs related to product development, I can purchase all the components and I have an R&D laboratory with everything I need. I am in prototyping and small series production business from over 12 years, just in another area (fleet management and gps tracking devices). The real issue with the costs will be with CE and FCC certifications.