Any of four rooms at NASA's launch control centre, used for all aspects of the checkout and launch phase for space vehicles. The rooms are located on the third floor of the centre, each having a checkout, control, and monitor subsystem (CCMS). Firing Rooms 1 and 3 are designed for the full control of launch and orbit operations. Firing Room 2 is normally used for the development and testing of computer software. Engineering analysis and support of the checkout and launch operations is carried out in Firing Room 4.