What is the volume of the waste gas generated by the combustion of coke oven gas?

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How many m3 of exhaust gas are produced when 1 m3 of coke oven gas is completely burned? Many books calculate based on the composition of gas components, using chemical equations. For example: The composition of coke oven gas is as follows: H2, CH4, CO, CnHm, CO2, O2, N2, H2O – 62.91%, 21.89%, 5.51%, 1.86%, 2.13%, 0.49%, 5.22%, 2.35%. Based on the composition of the gas and the chemical reaction equations with oxygen, the theoretical amount of oxygen required (as well as the amounts of products formed after combustion) can be calculated, as shown in the table below.

| Gas component | Percentage | Reaction equation | Theoretical oxygen consumption | VCO2 | VH2O | VN2 | VO2 | Volume in m3/m3 of gas |
|---------------|------------|-------------------|------------------------------|------|------|-----|-----|------------------------|
| H2 | 60.56 | H2 + 0.5O2 = H2O | 0.5 | 31.28| 60.56| | | |
| CH4 | 21.89 | CH4 + 2O2 = CO2 + 2H2O | 2 | 43.78| 21.89| 43.78| | |
| CO | 5.51 | CO + 0.5O2 = CO2 | 0.5 | 2.76 | 5.51 | | | |
| CnHm | 1.86×0.8 | C2H4 + 3O2 = 2CO2 + 2H2O | 3 | 4.46 | 2.98 | 2.98| | |
| | 1.86×0.2 | C6H6 + 7.5O2 = 6CO2 + 3H2O | 7.5 | 2.79 | 2.23 | 1.12| | |
| CO2 | 2.13 | | | 2.13 | | | | |
| O2 | 0.49 | | | | -0.49| | | |
| N2 | 5.22 | | | | | 5.22| | |
| H2O | 2.35 | | | | | | 2.35| |

Theoretical values for oxygen consumption and product amounts: 84.76, 34.74, 113.14, 5.22. The actual amount of air required, along with the amounts of oxygen and nitrogen introduced, are as follows:
L_actual = α × L_theoretical = α × O_theoretical × (100/21)
1.3 × 84.76 × (100/21) = 523.6
523.6 × 0.0235 × 0.6 = 7.34
524.70 × 0.79 = 413.64
523.6 × 0.21 – 84.58 = 25.38

The amounts of various components in the exhaust gas, in m3: 34.74, 120.52, 415.99, 25.38, 596.63. The volume percentage composition of the exhaust gas: 5.82%, 20.20%, 69.72%, 4.25%, 100.00%.

Note: CnHm is calculated based on 80% C2H4 and 20% C6H6. The saturation temperature of the gas is 20°C, with a relative humidity of 0.6. The air excess factor α is 1.3. In other words, when 100 m3 of coke oven gas burns completely, 596.63 m3 of exhaust gas is produced. That is, when 1 m3 of coke oven gas burns completely, approximately 6 m3 of waste gas is produced. What I don’t understand is: at what temperature is the volume of gas and exhaust gases referred to? If it were all under standard conditions (1 atmosphere, 0°C), the water in the exhaust gases would have long since condensed into liquid water. The table still calculates based on gaseous water.