The invention is a manhole construction safety and work platform device having a scaffold catwalk for working on a manhole, providing the safety and work platform with adjustable braces engaging the side of a conical manhole casing. The inner perimeter of the device circumferentially defines a central access opening in order to slidably accept, receive, and fit around the conical section of the manhole casing, as typically used in the utility construction industry. The scaffold catwalk has a safety barrier means on the working surface to provide a safe working environment along the outer perimeter. As is common in the industry, the conical section of the manhole casing may be an asymmetrical conical section. One objective of the present invention is to provide a scaffolding platform supported with at least three adjustable brace members to securely support the said platform against the sidewall of any shape of manhole casing.