Testing of Oxygen in Boeing aircrafts

[extricate]

Hi,

This is mainly for B777 fleet for guess most or all of the Boeing fleet has the same oxygen system.

There are two switches, RESET/TEST and EMERGENCY/TEST buttons. My company policy is to hold on to INT and press RESET/TEST, there should be oxy flow through speaker and yellow cross displayed, after which, release INT and hold on to both RESET/TEST and EMERGENCY/TEST buttons and yellow cross is displayed with PSI not dropping more than 50psi.

My ques is, when you test for oxygen, do you hold onto INT and both RESET/TEST and EMERGENCY/TEST buttons at the same time or just the RESET/TEST button and then as per above?

Thanks