×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Water content of Halon 1301

Water content of Halon 1301

Water content of Halon 1301

(OP)
I hope the expert in here could give me a hand.
I got a Halon 1301 (CF3Br) with water content in ppm for gaseous volumn/volumn and mg-H2O/L.
#1 How do I convert it to ppm by weight?
#2 What's the meaning of letter w in ppm w/w?

Any reference book or web-site is recommended?
Thanks a lot for your help!!

RE: Water content of Halon 1301

I'm not an expert, so I could be wrong but my understanding is that by definition, ppm is a volume measurement (ie, ml/kl).  Using the w/w means it is weight over weight (ie, mg/kg).  Without the w/w suffix it is assumed to be volume based.  As for converting to a weight basis, you could look up the densities of the components at the T and P conditions you're interested in and convert from volumes to weights.  

RE: Water content of Halon 1301

ppm can be on a volume, mass or mole basis.  For gases, mol and vol percentages are typically taken as equal unless they apply to pressure and temperature which compressibility factors for the two (or more) components must be taken into account.  For liquids and solids, mol%, vol% and mass% are all different.  Athough there are conventions which 'typically' applies to a specific phase, one should always define it to be unambigious.

For Freon which the water is reported in mg/L, the mg is the number of milligrams of water per litre of either dry Freon or total liquid (water plus Freon).  You really need to talk to the lab that did the testing to understand what basis they are referring to but if the water content is low, the difference between mg H2O per litre of dry Freon or 'wet' Freon will be insignificant.  

Convert a litre of Freon (which ever basis you use) to mass and you can determine, on a mass basis the ppm for the water content.  Similarly, you can convert to determine on a vol% or mol%.  Crunch the numbers both way to see the difference.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources