2.3.16 Sulfurous acid resistance (1) Testing A pair of connectors as fitted shall be left for 8 hours in the sulfurous acid gas kept at an atmosphere temperature of 40C, concentration of 500 ppm and humidity of 90% thru 95% of more. Taken them out of the tank and promptly determine their resistance to sulfurous acid gas. (2) Performance After tested, the connector shall satisfy the requirements specified in the following sections: 2.2.1 Voltage drop 2.2.13 Airtightness 2.3.17 Ozone resistance (1) Testing A pair of connectors as fitted shall be hanged in a hermetically sealed container kept at 40±2C. After leaving them in the ozone of 50±5C PPHN for 24 hours as provided for in Section 16.4 for JIS K6301, take out and leave them at the room temperature. (2) Performance After tested, the connector shall satisfy the requirements specified in the following sections: 2.2.1 Voltage drop 2.2.13 Airtightness