What is the maximum altitude to use the EMER DEPRESS switch?

The maximum altitude at which the EMER DEPRESS switch can be effectively used is 15,000 feet. This switch is utilized primarily to rapidly depressurize the aircraft cabin in emergencies, facilitating quick descent to safer altitudes where oxygen levels are adequate for crew and passengers. Above this altitude, the air pressure and density may make deploying the switch less effective or result in increased cabin altitude issues.

Also, the limits surrounding airspeed capabilities, such as 200 KIAS and 280 KIAS, refer to different operational parameters unrelated to altitude for the use of the EMER DEPRESS switch. These speeds are essential for maintaining control and safe operating conditions of the aircraft but do not change the critical altitude consideration for emergency depressurization. Therefore, maintaining the correct altitude bound is crucial to ensure the system operates safely and effectively.