Dipping and coating

Scope

OSHA’s dipping and coatings requirements apply to when you use a dip tank containing a liquid other than water. It applies when workers use the liquid in the tank or its vapor to:

Regulatory citations

• 29 CFR 1910.123 — Dipping and coating operations: Coverage and definitions
• 29 CFR 1910.124 — General requirements for dipping and coating operations
• 29 CFR 1910.125 — Additional requirements for dipping and coating operations that use flammable liquids or liquids with flashpoints greater than 199.4° F (93° C)
• 29 CFR 1910.126 — Additional requirements for special dipping and coating operations

Key definitions

• Adjacent area: Any area within 20 feet (6.1 m) of a vapor area that is not separated from the vapor area by tight partitions.
• Approved: The equipment so designated is listed or approved by a nationally recognized testing laboratory, as defined by 1910.7.
• Autoignition temperature: The minimum temperature required to cause self-sustained combustion, independent of any other source of heat.
• Dip tank: A container holding a liquid other than water and that is used for dipping or coating. An object may be immersed (or partially immersed) in a dip tank or it may be suspended in a vapor coming from the tank.
• Flammable liquid: Any liquid having a flashpoint at or below 199.4° F (93° C).
• Flashpoint: The minimum temperature at which a liquid gives off a vapor in sufficient concentration to ignite if tested in accordance with the test methods in Appendix B to 1910.1200—Physical Hazard Criteria.
• Lower flammable limit (LFL): The lowest concentration of a material that will propagate a flame. The LFL is usually expressed as a percent by volume of the material in air (or other oxidant).
• Vapor area: Any space containing a dip tank, including its drain boards, associated drying or conveying equipment, and any surrounding area where the vapor concentration exceeds 25 percent of the LFL of the liquid in the tank.

Summary of requirements

Employers must:

• Assess their workplace for any dipping and coating operations.
• Provide adequate ventilation. There are various options, depending on the operation and chemical.
• Follow permit-required confined space requirements when employees enter a dip tank.
• Provide medical and first-aid solutions.
• Provide an eyewash/shower.
• Provide hygiene facilities such as change rooms.
• Inspect exhaust ventilation at least quarterly; inspect dip tanks periodically.
• Follow the additional requirements in 1910.125 for dipping and coating operations that use flammable liquids or liquids with flashpoints greater than 199.4° F (93° C).
• Follow the additional requirements in 1910.126 for special dipping and coating operations, such as hardening and tempering, flow coating, bonding and grounding, vapor degreasing, cyanide tanks, and spray cleaning and degreasing tanks.