(For further information on accessibility, consult the Florida Building Code.) The walking surfaces of the means of egress must be slip-resistant and firmly fastened. Sloped surfaces should be utilized when variations in elevation of less than 12 inches (305 mm) exist in the means of egress. All doors used as access points to these areas must be wide enough for a person to pass through comfortably and have clear floor space inside the door zone. Door swings must be at least 36 inches (914 mm) wide. Openings in fireproof partitions or walls for smoke detectors or other equipment must be no smaller than 32 inches by 48 inches (813 mm by 122 mm). Fire extinguishers in workplaces under 10,000 pounds (4,540 kg) of pressure capacity must be of the non-carbonating type and located so that an individual can reach them in 90 minutes. All construction materials must be safe for use in buildings. This includes wood, paper, cloth, metal, and glass. Products containing lead or mercury are not permitted in new construction. These elements must also be removed from existing structures if they are to remain in good condition. Repair work may only be done with approved replacement parts. Any changes made to meet local building codes should be reported to a licensed architect or professional engineer. They will be able to advise you of any required code modifications or alterations that may not be obvious in a home inspection.