What Are The Osha Regulations For Spray Booths?

Spray booths are enclosed structures used for spray finishing operations in automotive, aerospace, furniture, appliance, and other manufacturing industries. They are designed to contain and ventilate overspray and solvent vapors while providing a clean, well-lit environment for applying liquid coatings such as paint, powder, or epoxy to products. Spray booths protect workers from hazardous exposures and prevent contamination of the facility and environment.

There are several types of spray booths including crossdraft, downdraft, sidedraft, open face, and semi-downdraft designs. They all function to draw contaminated air away from the operator’s breathing zone, filter overspray particles, and exhaust clean air to the atmosphere. Proper spray booth ventilation, gas handling, fire protection, and maintenance ensures a safe application environment.

Spray finishing generates significant hazards such as fire/explosion from accumulated residues and health effects from exposure to airborne toxins. OSHA regulations and national consensus standards mandate certain requirements to mitigate these hazards and provide guidance on spray booth operation and maintenance.

OSHA Standards for Spray Finishing

The main OSHA standard covering spray finishing operations is 29 CFR 1910.107. This comprehensive standard establishes requirements for ventilation, fire protection, electrical equipment, personal protective equipment, compressed gases, air hoses, operating procedures, and inspection and maintenance of spray finishing areas.

Some key aspects of 29 CFR 1910.107 include:

• Spray booths must have an average air velocity over the open face of the booth of at least 100 feet per minute.
• Spray booths must be equipped with mechanical ventilation that provides uniform air flow across the booth.
• Electrical wiring and equipment inside spray booths must meet the requirements for Class I, Division 1 hazardous locations.
• Workers must wear respiratory protection and protective clothing as needed for the materials being sprayed.
• Spray finishing equipment must be inspected periodically and maintained in safe operating condition.

Compliance with 29 CFR 1910.107 is mandatory for all general industry spray finishing operations covered by OSHA.

Ventilation Requirements

OSHA requires proper ventilation in spray booths to keep airborne concentrations of flammable materials below 25% of the lower explosive limit (Spray finishing using flammable and combustible materials.). The ventilation system must provide an air velocity between 100-150 feet per minute across the booth’s cross sectional area (1926.66 – Criteria for design and construction of spray booths). This continuous air movement helps remove solvent vapors and paint mists from the booth, protecting workers from hazardous exposure.

Fire Protection

According to OSHA regulation 1910.107, spray booths must be protected by automatic sprinklers where this protection is available. If automatic sprinklers are not available, then an alternate fire protection system must be provided. Portable fire extinguishers must also be provided near spray finishing operations.

The OSHA interpretation letter from August 12, 2004 states that federal OSHA enforces 1910.107, which requires automatic sprinklers for spray booth operations. However, state OSHA agencies may have additional requirements beyond the federal standards. For example, some states require sprinklers for all spray booth operations regardless of availability.

In summary, OSHA requires the following for fire protection of spray booths:

• Automatic sprinklers, where available
• Alternate fire protection system, if sprinklers are not available
• Portable fire extinguishers located near spray operations

It’s important to consult both federal OSHA regulations as well as state and local fire codes to ensure spray booth fire protection meets all applicable standards.

Electrical Equipment

Spray booths must have electrical wiring and equipment suitable for hazardous locations where volatile flammable materials may be present. All electrical wiring and equipment inside or within 20 feet of the spray booth must meet National Fire Protection Association (NFPA) standards for Class I, Division 1 hazardous locations, as specified in OSHA regulation 29 CFR 1910.107(b)(7)

OSHA requires that all electrical wiring and equipment in spray booth areas be adequately grounded to prevent static electricity buildup. All conductive objects in the spray area, such as floors and spray booth components, must have an electrical resistance no greater than 1 million ohms. This is to prevent static sparks that could ignite vapors or mists from spray finishing. Per OSHA standard 29 CFR 1910.107(g)(2), anything capable of carrying a charge must be grounded including paint containers, wash cans, and any other grounded conductive objects.

Personal Protective Equipment

OSHA has specific requirements for personal protective equipment for spray finishing operations to protect workers from hazardous materials. This includes:

• Respirators – Workers must wear NIOSH-approved respirators suitable for the material being sprayed. Air purifying respirators must have the correct cartridge/filter for the hazards. Supplied air respirators may also be required for some materials. See OSHA standard 1910.134 for detailed respirator requirements. Workers must also be fit tested and trained on respirator use.
• Protective clothing/gear – Impermeable protective clothing must be worn to protect against chemical contact. This can include suits, gloves, hoods, footwear, and eye protection. All potentially exposed skin must be covered. Contaminated clothing must be properly removed and disposed of. See OSHA interpretation letter for details.

Following OSHA’s standards for proper respiratory protection and protective gear is essential in spray finishing to shield workers from hazardous chemical exposures.

Compressed Gases & Air Hoses

Compressed gases used for spray finishing operations present both fire and explosion hazards. OSHA requires that gases be stored, handled, and used according to Compressed Gas Association guidelines (1910.107).

Compressed gas cylinders must be secured in an upright position at all times to prevent tipping or falls. They should be stored in cool, dry, well-ventilated areas away from heat sources and combustible materials. Valve protection caps must be in place when cylinders are not in use or connected to equipment (1926.66).

Compressed gas hoses must be inspected regularly for damage, defects, leaks, wear, and flexibility issues. Defective hoses must be removed from service immediately. Hoses should only be used for their intended purpose within safe pressure limits. Safety devices must be installed to prevent flashback and backflow issues.

Operating Procedures

OSHA requires specific operating procedures to be followed when working with spray finishing operations. According to OSHA standard 29 CFR 1926.66 (https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926.66), the following procedures must be posted and enforced:

Spraying should only be done in designated spray booths or rooms. Open flaming and spark producing equipment must be kept away from spraying areas.

Spraying equipment must be grounded to prevent static sparks. Only approved spray guns should be used.

Spraying should be done using proper techniques – spraying perpendicular to the surface, using even strokes, and keeping the gun nozzle 6 to 8 inches from the surface (https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926.66). Overspray and drift should be minimized.

All overspray deposits must be cleaned regularly and safely per OSHA guidelines.

Inspection & Maintenance

Regular inspection and maintenance of spray booths is critical to ensure ongoing compliance with OSHA regulations. Per OSHA standard 1910.107, spray booths must be inspected at frequent and regular intervals, with inspection records maintained and made accessible to OSHA inspectors upon request.

Filters should be visually checked daily to ensure proper function and replaced when airflow is reduced. Per SpraySystems.com, exhaust filters should be cleaned or replaced when the pressure drop reaches a maximum of 1.0 inches of water gauge. Thorough cleaning of the booth should be conducted at least once a week.

All instruments and controls should be calibrated and checked on a periodic basis, according to manufacturer specifications. This includes checking that ventilation rates meet OSHA’s minimum air velocity standards. Any deficiencies identified should be repaired immediately.

Proper maintenance procedures and schedules must be established and documented. Maintenance records should include the date of inspection, findings, repairs made, and names of personnel conducting the inspection and making repairs.

Training

OSHA requires employers to provide initial and recurrent training for employees that use spray finishing equipment. According to OSHA 1926.66, initial training must cover the hazards of spray finishing materials, equipment, and operations. Employees must understand proper operating procedures, maintenance requirements, and how to use personal protective equipment properly.

Refresher safety training must be provided at least annually, according to OSHA 1910.107. The training should focus on safe work practices and procedures, as well as any new developments with spray equipment, materials, or processes. Accident analysis should inform the refresher training program. Records of all training must be maintained.