#Code figure	Code figure	Meaning
0	0	Air
1	1	Ozone
2	2	Water vapour
3	3	Methane
4	4	Carbon dioxide
5	5	Carbon monoxide
6	6	Nitrogen dioxide
7	7	Nitrous oxide
8	8	Nitrogen monoxide
9	9	Formaldehyde
10	10	Sulphur dioxide
11	11	Nitric acid
12	12	All nitrogen oxides (NOy) expressed as nitrogen
13	13	Peroxyacetyl nitrate
14	14	Hydroxyl radical
15	15	Ammonia
16	16	Ammonium
17	17	Radon
18	18	Dimethyl sulphide
19	19	Hexachlorocyclohexane
20	20	Alpha hexachlorocyclohexane
21	21	Elemental mercury
22	22	Divalent mercury
23	23	Hexachlorobiphenyl
24	24	NOx expressed as nitrogen
25	25	Non-methane volatile organic compounds expressed as carbon
26	26	Anthropogenic non-methane volatile organic compounds expressed as carbon
27	27	Biogenic non-methane volatile organic compounds expressed as carbon
40000	40000	Sulphate dry aerosol
40001	40001	Black carbon dry aerosol
40002	40002	Particulate organic matter dry aerosol
40003	40003	Primary particulate organic matter dry aerosol
40004	40004	Secondary particulate organic matter dry aerosol
40005	40005	Sea salt dry aerosol
40006	40006	Dust dry aerosol
40007	40007	Mercury dry aerosol
40008	40008	PM10 aerosol
40009	40009	PM2P5 aerosol
40010	40010	PM1 aerosol
40011	40011	Nitrate dry aerosol
40012	40012	Ammonium dry aerosol
40013	40013	Water in ambient aerosol
65535	65535	Missing
