Fruit and Crop Ripening

This chapter establishes safety requirements for the ripening of fruits, vegetables, and other crops using ethylene gas in purpose-built rooms and enclosures.

1601 — General

1601.1 Scope. Ripening processes where ethylene gas is introduced into a room to promote the ripening of fruits, vegetables and other crops shall comply with this chapter.

Exception: Mixtures of ethylene and one or more inert gases in concentrations which prevent the gas from reaching greater than 25 percent of the lower explosive limit (LEL) when released to the atmosphere.

1601.2 Permits. Permits shall be required as set forth in Section 105.6.

1601.3 Ethylene generators. Approved ethylene generators shall be operated and maintained in accordance with Section 1606.

Worked example

Scenario: A large food distribution center plans to construct new ripening rooms for bananas and avocados. They need to ensure their design and operational procedures comply with the code.

Explanation: This section confirms that the new banana and avocado ripening rooms, which will use ethylene gas, must adhere to all the requirements outlined in Chapter 16, including specific rules for gas handling, ignition sources, waste, and equipment.

1602 — Definitions

1602.1 Terms defined in Chapter 2. Words and terms used in this chapter and defined in Chapter 2 shall have the meanings ascribed to them as defined therein.

1603 — Ethylene Gas

1603.1 Location. Ethylene gas shall be discharged only into approved rooms or enclosures designed and constructed for this purpose.

1603.2 Dispensing. Valves controlling discharge of ethylene shall provide positive and fail-closed control of flow and shall be set to limit the concentration of gas in air below 1,000 parts per million (ppm).

Worked example

Scenario: An architect is designing a new fruit ripening facility. The client wants to place the ethylene gas cylinders and discharge points in a general warehouse area for convenience.

Explanation: This section prohibits discharging ethylene gas in general warehouse areas. The design must include dedicated, approved rooms or enclosures specifically constructed for the ripening process and ethylene gas discharge to ensure safety.

1604 — Sources of Ignition

1604.1 Ignition prevention. Sources of ignition shall be controlled or protected in accordance with this section and Chapter 3.

1604.2 Electrical wiring and equipment. Electrical wiring and equipment, including luminaires, shall be approved for use in Class I, Division 2, Group C hazardous (classified) locations.

1604.3 Static electricity. Containers, piping and equipment used to dispense ethylene shall be bonded and grounded to prevent the discharge of static sparks or arcs.

1604.4 Lighting. Lighting shall be by approved electric lamps or luminaires only.

1604.5 Heating. Heating shall be by indirect means utilizing low-pressure steam, hot water or warm air.

Exception: Electric or fuel-fired heaters approvedfor use in hazardous (classified) locations which are installed and operated in accordance with the applicable provisions of NFPA 70, the International Mechanical Code or the International Fuel Gas Code.

Worked example

Scenario: A ripening room operator uses portable electric heaters to maintain temperature during colder months. The heaters are standard shop models with exposed heating elements.

Explanation: This section requires that all ignition sources, including electrical equipment like heaters, be controlled or protected. Standard heaters with exposed elements are likely prohibited in a room where a flammable gas like ethylene is present, requiring specialized explosion-proof or intrinsically safe alternatives.

1605 — Combustible Waste

1605.1 Housekeeping. Empty boxes, cartons, pallets and other combustible waste shall be removed from ripening rooms or enclosures and disposed of at regular intervals in accordance with Chapter 3.

Worked example

Scenario: After unloading a shipment of produce into a ripening room, the empty cardboard boxes and wooden pallets are left inside until the next shift for later removal.

Explanation: This section mandates regular removal and disposal of combustible waste such as empty boxes and pallets from ripening rooms. Leaving them inside creates a fire hazard and violates the required housekeeping standards.

1606 — Ethylene Generators

1606.1 Ethylene generators. Ethylene generators shall be listedand labeledby an approved testing laboratory, approved by the fire code official and used only in approved rooms in accordance with the ethylene generator manufacturer's instructions. The listing evaluation shall include documentation that the concentration of ethylene gas does not exceed 25 percent of the lower explosive limit (LEL).

1606.2 Ethylene generator rooms. Ethylene generators shall be used in rooms having a volume of not less than 1,000 cubic feet (28 m3). Rooms shall have air circulation to ensure even distribution of ethylene gas and shall be free from sparks, open flames or other ignition sources.

Worked example

Scenario: A fruit distributor purchases a new, unlisted ethylene generator from an overseas supplier, believing it to be more cost-effective.

Explanation: This section requires ethylene generators to be listed and labeled by an approved testing laboratory and approved by the fire code official. An unlisted generator from an overseas supplier would not meet these critical safety and approval requirements.

1607 — Warning Signs

1607.1 When required. Approved warning signs indicating the danger involved and necessary precautions shall be posted on all doors and entrances to the premises.

Worked example

Scenario: A small produce market has a ripening room for bananas, but the only sign on the door is a 'Staff Only' notice.

Explanation: This section requires approved warning signs indicating the danger and necessary precautions to be posted on all doors and entrances to the premises where ethylene ripening occurs. A simple 'Staff Only' sign is insufficient for informing personnel and emergency responders of the specific hazards.

Frequently asked questions

What types of ripening processes are regulated by this chapter?

This chapter applies to ripening processes that involve introducing ethylene gas into a room to promote the ripening of fruits, vegetables, and other crops.

Where is ethylene gas permitted to be discharged for ripening?

Ethylene gas must be discharged only into approved rooms or enclosures that are specifically designed and constructed for this purpose.

What are the requirements for ethylene generators?

Ethylene generators must be listed and labeled by an approved testing laboratory, approved by the fire code official, and used strictly in approved rooms according to the manufacturer's instructions.