FSS vs ACM Comparison

Federal Signal Corp designs and manufactures products and integrated solutions for municipal, governmental, industrial, and airport customers. It operates through two segments. The Environmental Solutions Group manufactures and supplies street sweeper vehicles, sewer cleaner and vacuum loader trucks, hydro-excavation trucks, high-performance water blasting equipment, dump truck bodies, and trailers. The Safety and Security Systems Group manufactures and supplies comprehensive systems and products used by law enforcement, fire rescue, and industrial sites to protect people and property. Its offerings include systems for community alerting and industrial communications. The company generates the majority of its revenue from the Environmental Solutions Group segment.

Aecom is one of the largest global providers of advisory, design, and engineering services. It serves a broad spectrum of end markets, including water, transportation, and environment. Based in Dallas, Aecom employs 51,000 people. The company generated $16.1 billion in sales in fiscal 2025.