Inhalation Exposures to Particulate Matter and Carbon Monoxide during Ethiopian Coffee Ceremonies in Addis Ababa: A Pilot Study

Table 4

Carbon Monoxide Concentration Data (ppm).

Site	Highest 15-minute average		Highest 30 minute average		Highest 60 minute average
	Personal	Area	Personal	Area	Personal	Area
1	120A	90A	110B	88A	95B	85B
2	58	71	55A	61A	46A	48A
3	35	36	32	27	31A	22
4	58	47	49	40	46A	37A
5	58	31	26	45	32A	19
6	56	34	32	50A	50B	31A
7	52	14	13	45	39A	13
8	37	19	15	25	21	11
9	115A	74	57A	86	74B	49A
10	38	40	33	34	24	28A
Median	57	38	32.5	45	42.5	29.5
GM	57	39	35	46	41	29
GSD	1.53	1.81	1.89	1.54	1.60	1.88

A: Exceeds the WHO guideline
B: Exceeds twice the WHO guideline
WHO guidelines—concentrations not to be exceeded for averaging times, 15 minute: 90 ppm, 30 minutes: 50 ppm, 60 minutes: 25 ppm [12].