1. B Floor sample

2. Blips in images, caused by foam de-gassing – charge effects.

5. A B C

6. Similar magnification for the two filters J Floor B Floor Many more particles on the B floor filter

8. A a b c d e

9. a b c d e be d c a Mg Cl S Fe Ca K Cl S

10. A B C

12. a b c d e f g h

13. a b c d e f g h d e a b c g hf Si C C C C C Fe Ca K K K K S S K Al

14. A B C

15. C

16. b a d c e g f

17. b a d c e g f b g d a e f c g Si Ba Ca S C Al K C Ca Cl Al S O O

18. Overview - after

20. Particle Size: Many sub micron, quite a lot >10um, some extending more than 50um Particle Composition: Much more varied. Same element as before, plus Ba.

21. J-Floor Sample B-Floor Sample SizeAll less than ~10um, most <2um Many sub micron, quite a lot >10um, some extending more than 50um CompositionMainly: Si, Ca, C, Fe Some: Cl, K, S, Mg, O, Al Mainly: Si, Cl, Ca, Mg, Ba, S, C, Al, Zn, Na Some: K, Fe, O Initial Comparison

22. C % is similar for both Si % - much higher for the B floor sample S % - variable – highest % on J Na % - much higher for B floor sample K % - generally low, not more than 2% Ba % - much higher for B floor sample P % - variable Ca % - much higher for J floor sample Cl % - one case of v.high % on B floor, otherwise low Al % - generally low O % - variable Zn % - generally only present on B floor sample, but small quantities N % - possibly more on the J floor sample….prob due to scarcity of particles and higher chance of interacting with gas in chamber