Arapahoe smoke chamber

Table XIII. Arapahoe Smoke Chamber Tests % of weight burned...

In the present study DSC and TGA data were run on DuPont 910 and DuPont 951 instruments, respectively. Arapahoe Smoke Chamber results were obtained on a commercial apparatus. Coated samples used were commercially prepared zinc arc spray samples on Noryl FN 215 Structural Foam. 

An initial experiment involved determination of Arapahoe Smoke Chamber results for samples with and without the zinc coating present. Data are presented in Table II. Depending upon orientation of the sample, an increase in char occurred for some samples with zinc present, while no change in smoke formation was seen. Initial pyrolysis GC/mass spectroscopy results at 90CPC in helium showed no difference in volatiles formed with or without zinc. These results suggested enhanced char formation as the origin of the Radiant Panel results for zinc on modified-polyphenylene oxide (m-PPO). Zinc oxide is a known, effective thermal stabilizer in the alloy. The next work then focused on DSC/TGA studies. 

Table II. Arapahoe Smoke Chamber Data for Modified-PPO and Zn ...

Molybdenum compounds are effective in PVC, especially when coupled with zinc compounds. In addition, these compositions are flame-retardant. For example, 1.5 phr. of Sb20s and 1.5 phr. of Kemgard 911 in plasticized PVC raised the oxygen index from 28 to 33.5 % while the mass of solid particles filtered from the combustion products in an Arapahoe smoke chamber (cf. Fig. 4.1 in Section 4.1.1.1) lessened by 32.6 per cent. 4 phr. of the same additives in rigid PVC enhanced the oxygen index from 41 to 58 % and reduced smoke production by 48 per cent. ... 

Arapahoe Smoke Chamber this test employs a cylindrical combustion chamber with a chimney connected to a vacuum source. Al.5x0.5x0.125... 

Table XIV. Comparison of NBS Smoke Chamber Data (Flaming) with Arapahoe Smoke ...

Hilado C. j. and Machado A. M., Smoke studies with the Arapahoe chamber. J. Fire Flammability , 9, 240-244 (1978). 

At present there are more than fifteen widely used different test methods to evaluate smoke, each employing its own unique set of heating conditions, sample size and orientation, gas flow and means of smoke measurement. The most frequently used tests are those based on optical methods, i.e. attentuation of a light beam due to the sample formulations burning. There are also mechanical methods, those based on separation of liquid and solid aerosol particles from the smoke gases, the Arapahoe method and electrical methods (generation of electrical charges in an ionization chamber). 

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