NFPA 33, Spray Application Using Flammable or Combustible Materials

The 2024 edition includes:

• Updated terminology to better align with NFPA 30, Flammable and Combustible Liquids Code
• New definitions for maximum allowable quantity and inflatable finishing workstations
• New requirements addressing spray finishing
• Revisions to Chapters 4 and 5 to align with International Fire Code requirements
• Added test requirements for materials used in wall or ceiling assemblies
• Simplified requirements and new requirements for total quantities of liquids allowed in mixing rooms
• Revisions to Chapter 9 to differentiate liquid spray operations from powder spray operations and add hybrid systems (water and inert gas) to the list of available fire protection systems

Table of Contents:

Chapter 1 Administration

1.1 Scope.
1.2 Purpose.
1.3 Application.
1.4 Retroactivity.
1.5 Equivalency.
1.6 Units and Formulas.
1.7 Enforcement. (Reserved)

Chapter 2 Referenced Publications

2.1 General.
2.2 NFPA Publications.
2.3 Other Publications.
2.4 References for Extracts in Mandatory Sections.

Chapter 3 Definitions

3.1 General.
3.2 NFPA Official Definitions.
3.3 General Definitions.

Chapter 4 General Requirements

4.1 Location of Spray Application Operations.
4.2 Separation.
4.3 Basements.
4.4 Fueled Vehicles.
4.5 Noncombustible Material.
4.6 Limited-Combustible Material.
4.7 Classification Scheme.
4.8 Determination of Flash Point (FP).

Chapter 5 Construction and Design of Spray Areas, Spray Rooms, and Spray Booths

5.1 Spray Areas.
5.2 Spray Rooms.
5.3 Spray Booths.
5.4 Conveyor Openings.
5.5 Separation from Other Operations.
5.6 Illumination and Observation Panels.
5.7 Ventilation.

Chapter 6 Electrical and Other Sources of Ignition

6.1 Scope.
6.2 General.
6.3 Electrical Area Classification.
6.4 Electrical Devices in Spray Areas.
6.5 Electrical Devices in Areas Adjacent to or Connected to Spray Areas.
6.6 Illumination.
6.7 Static Electricity.
6.8 Flexible Power Cords.
6.9 Portable Electric Luminaires.
6.10 Movement of Powered Vehicles.

Chapter 7 Ventilation

7.1 General.
7.2 Performance Requirements.
7.3 Make-Up Air.
7.4 Routing of Exhaust Ducts.
7.5 Recirculation of Exhaust.
7.6 Heating of Recirculated Air.
7.7 Manifolding of Exhaust Ducts.
7.8 Materials of Construction.
7.9 Support of Exhaust Ducts.
7.10 Exhaust Duct Access Openings.
7.11 Exhaust Fans and Drives.
7.12 Drying Areas.

Chapter 8 Storage, Handling, and Distribution of Ignitible (Flammable and Combustible) Liquids

8.1 General.
8.2 Storage in Process Areas.
8.3 Handling and Use.
8.4 Distribution Systems — Piping.
8.5 Distribution Systems — General.

Chapter 9 Protection

9.1 General.
9.2 Ventilation Systems.
9.3 Coating Material Delivery Systems.
9.4 Conveyors.
9.5 Protection Systems.
9.6 Specific Process Protection.
9.7 Protection for Electrostatic Precipitator Scrubber.
9.8 Protection for High-Capacity Dry Paint Arrestor.

Chapter 10 Operations and Maintenance

10.1 General.
10.2 Inspection, Testing, and Maintenance.
10.3 Combustible Residues.
10.4 High-Pressure Hose Lines.
10.5 Maintenance Procedures.
10.6 Waste Containers.
10.7 Clothing.
10.8 Cleaning Operations.
10.9 Solvent Distillation Units (Solvent Recyclers).
10.10 Spontaneous Ignition Hazards.
10.11 Chlorinated Solvents.
10.12 Smoking.
10.13 Hot Work.

Chapter 11 Automated Electrostatic Spray Equipment

11.1 Scope.
11.2 General.
11.3 Automated Electrostatic Systems.
11.4 Incendive Equipment.
11.5 Listing and Approval of Equipment.

Chapter 12 Handheld Electrostatic Spray Equipment

12.1 Scope.
12.2 General.
12.3 Handheld Apparatus.
12.4 Electrical Components.
12.5 Grounding.

Chapter 13 Drying, Curing, and Fusion Processes

13.1 General.
13.2 Spray Booths and Spray Rooms Used for Ambient Air Drying.
13.3 Spray Booths and Spray Rooms Used for Drying at Elevated Temperatures.
13.4 Liquefied-Petroleum-Gas, Compressed-Natural-Gas, or Hydrogen-Fueled Vehicles.
13.5 Radiant Drying Apparatus.
13.6 Flash-Off Areas.
13.7 Spray Booths or Spray Rooms Adjacent to or Connected to Rooms or Equipment Used for Drying, Curing, or Fusing.
13.8 Ventilation.
13.9 Warning Signs.

Chapter 14 Miscellaneous Spray Operations

14.1 Vehicle Undercoating and Body Lining.
14.2 Preparation Workstations.
14.3 Limited Finishing Workstations.
14.4 Inflatable Finishing Workstations.

Chapter 15 Powder Coating

15.1 Scope.
15.2 General.
15.3 Applicability.
15.4 Location.
15.5 Construction and Design of Spray Booths and Spray Rooms.
15.6 Electrical and Other Sources of Ignition.
15.7 Ventilation and Dust Collection.
15.8 Storage and Handling.
15.9 Protection.
15.10 Operation and Maintenance.
15.11 Automated Electrostatic Powder Spraying Equipment.
15.12 Handheld Electrostatic Powder Spraying Equipment.
15.13 Drying, Curing, and Fusing Equipment.
15.14 Electrostatic Fluid Beds.
15.15 Hot Flocking.
15.16 Fluid Bed Coating.

Chapter 16 Organic Peroxides and Plural Component Coatings

16.1 Scope.
16.2 General.
16.3 Prevention of Contamination.
16.4 Storage of Organic Peroxides.
16.5 Handling of Organic Peroxides.
16.6 Mixing of Organic Peroxides with Promoters.
16.7 Smoking.
16.8 Trained Personnel.
16.9 Material Safety Data Sheets.

Chapter 17 Styrene Cross-Linked Composites Manufacturing (Glass Fiber–Reinforced Plastics)

17.1 Scope.
17.2 Resin Application Equipment.
17.3 Fire Protection.
17.4 Resin Storage.
17.5 Electrical and Other Hazards.
17.6 Ventilation.
17.7 Use and Handling.

Chapter 18 Spray Application Operations in Membrane Enclosures

18.1 Scope.
18.2 Limitations.
18.3 Membrane Material.
18.4 Protection.
18.5 Personnel Inside the Enclosure.
18.6 Electrical and Other Sources of Ignition.
18.7 Ventilation.
18.8 Recordkeeping.
18.9 Storage and Handling of Ignitible (Flammable and Combustible) Liquids.
18.10 Facilities Compliance Permitting.

Chapter 19 Training

19.1 General.

Annex A Explanatory Material
Annex B Determining Lower Flammable Limits
Annex C Determining Ventilation Airflow for Powder Application Systems
Annex D Fire Record
Annex E Informational References