Each applicant for a gas fitter's license shall execute and deliver to the Clerk-Treasurer a good and sufficient surety bond in the sure of five thousand dollars ($5,000), to be approved by the City Attorney. Such bond shall be for the protection of the City against loss or damage by reason of carelessness, defective material or negligence on the part of the person furnishing such bond to properly execute, perform and protect any and all gas fitting work performed by him or under his supervision during the period of such gas fitter's license.