City
|
Sample number
|
Formaldehyde concentration (mg/m3)
|
Percentage above standardb (%)
|
---|
Mean ± SD
|
Range
|
---|
Beijing
|
530
|
0.210 ± 0.152
|
0.025–1.382
|
75.5
|
Tianjin
|
164
|
0.267 ± 0.170
|
0.025–1.100
|
89.6
|
Shanghai
|
182
|
0.205 ± 0.135
|
0.025–0.869
|
79.1
|
Chongqi
|
198
|
0.142 ± 0.084
|
0.025–0.461
|
64.6
|
Shizuishan
|
212
|
0.610 ± 0.311
|
0.104–1.712
|
100
|
Changchun
|
201
|
0.412 ± 0.208
|
0.025–1.243
|
96.0
|
Total
|
1,487
|
0.290 ± 0.238
|
0.025–1.712
|
82.3
|
- aSampling time: January to April 2003; time since renovation: <6 months
- bThe “Indoor air quality standard” of China (GB/T 18883-2002) stipulates the indoor limit of 0.10 mg/m3 (1-h average) for formaldehyde