Environmental foam blankets

Similar applications of foam blankets have been developed for the following parameters  

Where the vapours to be controlled are flammable, many of these foams are quite similar to the protein, fluoroprotein, and aqueous-film-forming foams used in firefighting [590,594,598] (see also Section 12.9). Where longer-term odour and toxicity control are more important many of these foams are polymer-thickened and gelling foams [592-594]. Other applications of foam blankets are discussed in Sections 10.5 and 13. 

---

Another characteristic of foam is the concentration in which it is used. A 3% foam concentrate is mixed at a ratio of 97 parts water to 3 parts foam concentrate. Similarly, a 6% foam concentrate is mixed at a ratio of 94 parts water to 6 parts foam concentrate. Another key consideration is the 25% drainage time—the time required for 25% of the foam s liquid to drain from the foam. This characteristic can be used to measure foam stability, and in combination with the expansion ratio, it can be used to determine how the thickness of the foam blanket will vary with time (NFPA 471, 1989). This dictates the rate at which foam will have to be added to the initial blanket to ensure continued mitigation effects. Second, the drainage time can be used to determine the water, both total quantity and rate, that will have to be dealt with to prevent the incident from becoming an environmental incident as well. 

The application of foam blankets as temporary covers for environmental applications was introduced in Section 9.6. Several kinds of foams have also... 

---