Approximately how many SCADA systems are in use worldwide?

• A. About 3 million systems in use
• B. About 300
• C. About 30 thousand
• D. About 30 million

Answer: (A)

SCADA systems are embedded across utilities, manufacturing, and critical infrastructure worldwide, so the global count is in the millions. When you account for large facilities, small plants, remote sites, and building automation, there are many thousands of installations in every region, and multiple SCADA servers or supervisory setups often exist within a single site. This makes a total on the order of millions plausible, with about 3 million serving as a reasonable global ballpark. The other numbers are too small to reflect the widespread adoption, or too large to match how a “system” is typically counted across diverse industries. So the best fit is approximately 3 million.