NFPA 30 Water Miscibility of Flammable Liquids

[arion]

Hi, a few inter-related questions regarding Flammable Liquids:

1. What are the best books/websites/other resources are there for reviewing an MSDS sheet to make an accurate determination of the water miscibility for each component chemical in the list in order to comfortably classify the chemical as a whole as "Water-Miscible" as defined in the NFPA 30?

2. The Fire Code also makes reference to an exception in Chapter 57 regarding cosmetic and foodstuffs etc. that are 50% water-miscible, where the rest of the liquid is not flammable. Does this other 50% include liquids that are "Combustible" (ie: Class II/IIIA/IIIB) or just Flammable as defined (ie: IA/IB/IC)?

3. Are there any minimum-percentage exceptions or other exceptions for flammable or combustible liquids that exclude them from being classified as flammable or combustible? Or does only Flash Point drive this determination?

4. Is there a "highest" flash point where a Class IIIB liquid ceases to be a IIIB and no longer considered a Combustible Liquid?

Thanks!

 

[stookeyfpe]

ANSWERS:

1) Very few liquids are truly water miscible. Search water solubility in a high school chemistry book and any college text for organic chemistry.
2) It's possible.
3) Flash point is just one predictor of the hazard of liquid as being flammable or combustible. Vapor pressure, process temperature, process pressure and viscosity are other factors.
4) No, and no rule of thumb or set value is prescribed. Some estimations have been made but a proper hazard analysis is required.

All my comments are based on a liquid in storage @ NTP.

 

[arion]

Thanks Stookey. Here are some follow up questions based on your responses.

1. Are there any particular high school chemistry books or college organic chemistry books you recommend that you typically use for your hazmat projects?

2. You mention water solubility. Is this synonymous with water miscibility then?

3. What course of action do you suggest in cases where the water miscibility/solubility is not noted in the MSDS sheet?

4. Is there other resources on how to perform a proper analysis on how to use the vapor pressure, process temperature, process pressure, and viscosity to determine classification? 95% of my applications are in a warehouse storage condition, typically not in use.

5. You mention a proper hazard analysis. Is there a specific analysis that can be performed to distinguish a IIIB from a non-combustible liquid?

Thanks again!

 

[cdafd]

So storage of material correct?

Are you overthinking this?

Most common materials are classified off the msds

Is there another reason for asking the question?

Are you looking at an existing storage setup or proposed ?

About how many gallons of chemicals are you talking about?

 

[stookeyfpe]

Arion:

Don't take this wrong but you need to do your own work on this issue. If you are not comfortable making these technical decisions then seek professional assistance. I have helped you before but your now starting to enter into a technical arena where you need to be able to classify the hazards most likely as a basis for occupancy classification and sprinkler design.

You asked and I answered as best as I can. And if you place all faith in MSDS some critical information could be missed.