Sewer Pipe Lining & Trenchless Repair

Instead of digging up streets, crews often repair old sewer pipes from the inside by pulling in a resin-soaked liner and curing it in place. The work goes through manholes and pipes, with strong chemicals, steam and sewer gas.

• Utility Crews
• Sewer Rehabilitation
• Contractors

Hazards

• Confined spaces: manholes and pipes can have low oxygen, hydrogen sulfide, methane and other gases. See Confined Spaces and Manholes & Vaults.
• Resin chemicals: styrene and other fumes from resin and curing. Styrene irritates eyes, nose and throat and affects the nervous system. Fumes can also escape into nearby buildings. See Solvents.
• Steam and hot water used to cure liners, causing burns and pressure hazards. See Steam Systems.
• Ultraviolet light curing lamps: eye and skin damage if exposed.
• Sewage: infectious exposure. See Sewage Exposure.
• Traffic at street work zones. See Traffic Control Crews.
• Heavy equipment, bypass pumps, hoses and lifting.
• Heat stress in protective clothing.

Controls

• Use a permit-required confined space program: test the air, ventilate, attendant outside, rescue plan and equipment ready
• Use gas detectors that read oxygen, flammable gas, hydrogen sulfide and carbon monoxide continuously. See Gas Detectors
• Control fumes: vent curing exhaust away from workers and buildings; notify nearby residents; use respirators with organic vapor cartridges where needed
• Keep steam hoses, fittings and boilers inspected; use burn-resistant gloves and clothing
• Wear UV-blocking eyewear and cover skin around UV equipment
• Set up traffic control with signs, cones and trained flaggers
• Wash hands, change clothes and keep food away from sewer areas
• Plan for rain and flash flows in sewers; do not enter if storm flows are possible

Last updated: October 8, 2026