Table 6.

Average, median, exceedances to the legislation and the p value of the difference between the hourly mean before and after implementation of IAP mitigation measure for the occupation period for CH₂O.

ME	(CH2O)in a						(CH2O)post b						p Value
	Avg c	Med d	Exceedances (%)				Avg c	Med d	Exceedances (%)
			WHO e		PL f				WHO e		PL f
CR1_A	134.82	90,83	41	✕	100	✕	129.36	105.47	59	✕	100	✕	0.730
CR1_B	88.04	87.52	28	✕	50	✕	56.03	52.45	0	✓	0	✓	0.002 *
JI1_A	28.71	27.62	0	✓	0	✓	34.76	36.77	0	✓	0	✓	0.605
PRIM1_A	35.82	41.70	0	✓	0	✓	36.92	40.09	0	✓	0	✓	0.959
PRIM1_B	21.37	18.56	0	✓	0	✓	9.57	5.27	0	✓	0	✓	0.169
RF1	20.09	15.89	0	✓	0	✓	49.05	46.68	8	✕	0	✓	0.100
JI2_A	63.74	65.43	0	✓	0	✓	71.87	74.83	0	✓	0	✓	0.073
PRIM2_A	80.57	76.55	18	✕	0	✓	688.37	757.95	100	✕	100	✕	<0.001
PRIM2_B	109.74	106.25	41	✕	100	✕	52.61	48.50	3	✕	0	✓	<0.001
PRIM2_C	82.11	79.01	0	✓	0	✓	102.46	87.93	35	✕	100	✕	0.931
CR3_A	277.70	282.23	80	✕	100	✕	91.51	73.90	20	✕	100	✕	<0.001
CR3_B	190.21	192.82	91	✕	100	✕	33.49	28.13	0	✓	0	✓	0.100
CR3_D1	87.47	91.24	17	✕	0	✓	82.61	87.59	33	✕	0	✓	0.700
CR3_D2	85.32	76.10	21	✕	50	✕	49.31	48.76	0	✓	0	✓	0.100
RF3	133.64	144.41	100	✕	100	✕	74.51	77.03	25	✕	0	✓	0.100

^a CH₂O concentration of first IAQ campaign; ^b CH₂O concentration of second IAQ campaign (after IAP mitigation measures implemented); ^c Average; ^d Median; ^e % of exceedances to the World Health Organization (WHO); ^f % of exceedances to the Portuguese legislation; * p < 0.05 (considered statistically significant) for the item in bold; ✕—Exceedances to the Portuguese legislation or WHO; ✓—No exceedances to the Portuguese legislation or WHO.