Table 1

Summarised personal sampling exposure data from NanoTracer

Site	Non-ENP handling activity			ENP handling activity			Ambient at laboratory/office where exposure measured
Site	Period (min)	Count (particles/mL air)	Mean diameter (nm)	Period (min)	Count (particles/mL air)	Mean diameter (nm)	Period (min)	Count (particles/mL air)	Mean diameter (nm)
Area 1	229	4663	61	42	1964	58	105	9650	n/a
Area 2	268	12 554	46	75	9061	54	119	10 722	42
Area 3	204	4227	78	727	3644	68	47	22 620	n/a
Area 4	150	11 699	46	295	8067	40	64	13 129	n/a
Area 5	78	5507	44	128	5035	46	64	13 129	n/a
Area 6	241	6073	36				326	31 571	n/a
Area 7	237	14 090	41				4	8434	35