Apr 2012

Lift Trucks – Choosing the Correct Type and Recommendations for Associated Hazards

Driver and safety training for lift truck operators are very important to industrial plant or distribution warehouse managers and owners for obvious reasons, with personnel safety at the top of the list. But what about the property loss prevention and fire safety issues associated with the various types of industrial trucks and the importance of selecting appropriate trucks for use in hazardous (Classified) locations?

There are several different types of industrial trucks; battery powered, gas fueled (including liquefied petroleum gas (LPG), compressed natural gad (CNG) and gaseous hydrogen fuel cells and cylinders), gasoline and diesel powered. There are also dual-fuel trucks that are equipped to be operated using either gasoline or LPG or to be operated using either gasoline or CNG without further modification. Battery powered and LPG fueled trucks are the most common.

A system (Type Designation) for identifying the types of powered industrial trucks for operation in non-classified and classified areas is listed in NFPA 505, Fire Safety Standard for Powered Industrial Trucks Including Type Designations, Areas of Use, Conversions, Maintenance, and Operations, and similarly in FM Global Property Loss Prevention Data Sheet 7-39, Lift Trucks. These designations are tabulated below:

Fuel Type and Special Design (if any)

Type

Designation

Electrical (Battery)

E

Electrically powered unit that, in addition to meeting all the requirements for Type E units, is provided with additional safeguards to the electric system to prevent the emission of hazardous sparks and to limit surface temperatures

ES

Electrically powered unit that, in addition to meeting all the requirements for Type E and ES units, has its electric motors and all other electric equipment completely enclosed

EE

Electrically powered unit in which the electric fittings and equipment are so designed, constructed, and assembled that the unit can be used in atmospheres containing specifically named flammable vapors, dusts, and, under certain conditions, fibers

EX

Gasoline

G

Gasoline powered unit that, in addition to meeting all the requirements for Type G units, is provided with additional safeguards to the exhaust, fuel, and electric systems

GS

Diesel

D

Diesel with additional safeguards to the exhaust, fuel, and electric systems

DS

Diesel-powered unit in which the diesel engine and the electric fittings and equipment are so designed, constructed, and assembled that the unit can be used in atmospheres that contain specifically named flammable vapors, dusts, and, under certain conditions, fibers

DX

Diesel-powered unit and any electric equipment is completely enclosed and equipped with temperature-limitation features

DY

LPG

LP

 LPG powered unit that is provided with additional safeguards to the exhaust, fuel, and electric systems

LPS

CNG

CN

CNG powered unit that is provided with additional safeguards to the exhaust, fuel, and electric systems

CNS

Dual Fuel – Gasoline/LPG

G/LP

A unit that operates on either gasoline or liquefied petroleum gas and is provided with additional safeguards to the exhaust, fuel, and electric systems

GS/LPS

Dual Fuel – Gasoline/CNG

G/CN

Unit that operates on either gasoline or compressed natural gas and, in addition to meeting all the requirements for Type G/CN units, is provided with additional safeguards to the exhaust, fuel, and electric systems

GS/CNS

Compressed Gaseous Hydrogen

H2

General property loss prevention and fire safety recommendations are provided below.

All Lift Trucks:

  • All lift trucks should have a designated location for parking trucks during idle periods separated from manufacturing and storage areas by a minimum space separation of 5 ft. (1.5 m) between the idle trucks and combustibles, or a 1 hr. rated fire-rated barrier between the garaging area and combustibles.
  • It is recommended that a designated location be provided for service and repair of trucks away from manufacturing and storage areas. The service/repair area should be separated by a minimum of 35 ft. (11 m) and any nearby combustibles, or again, a 1hr. fire-rated barrier.
  • Fire prevention procedures in the service and repair areas should be similar to those in an automobile service and repair shop. Section 8.6 in NFPA 505 lists a number of important recommendations and requirements.
  • Proper precautions and care should be taken during re-fueling operations and storage and handling of fuels.
  • Provide fire extinguishers suitable for a fire involving the fuel used in the lift truck as follows:
    • Equip each gasoline, LPG, diesel, gasoline/LPG, battery-powered, CNG, and hydrogen fueled lift truck with a minimum 5 lb (2.3 kg) dry chemical extinguisher rated for ignitable liquids and gases.
    • Provide a minimum 10 lb (4.5 kg) dry-chemical extinguisher at each gasoline or diesel refueling location rated for ignitable liquids and gases.

Battery Powered Trucks:

  • Electrical chargers should not be placed within storage racking. Battery-charging installations should be located in areas designated for such purpose. Multiple-panel battery-charging installations serving more than two trucks should be located in a separate area along an exterior wall (a cut off room is preferred). The areas shall be kept free of extraneous combustible materials. It is recommended that battery-charging installations have a minimum space separation of 10 ft. (3.0 m) and preferably 20 ft (6.0 m) from any combustibles.

Liquid (Gasoline and Diesel) Fueled Trucks:

  • The storage and handling of liquid fuels should be in accordance with NFPA 30 or NFPA 30A, as applicable.
  • Trucks using liquid fuels should be refueled only at locations designated for such purpose and should be refueled from approved dispensing pumps. Bonding and grounding should be provided between the hose nozzle or can spout and the tank to minimize accumulation of static electricity.
  • The engine should be stopped and the operator should not be on or inside the truck during refueling. Ensure the engine remains off during refueling.
  • Refuel gasoline and diesel powered trucks outdoors or in a well-ventilated, detached building.
  • Exercise care to avoid spilling fuel or overfilling the tank. Ensure spilled fuel has dissipated or been flushed away before starting the engine.
  • Smoking or open flames should be prohibited in the refueling area.

Gas Powered Trucks:

  • The storage and handling of LPG should be in accordance with NFPA 58. The storage and handling of CNG and hydrogen should be in accordance with NFPA 52. Preferably, store spare LPG and CNG cylinders outdoors.
  • Preferably, provide an outdoor shelter, or a detached building of light-weight noncombustible construction, for storage of lift trucks when not in use.
  • If gas fuel trucks are stored indoors provide all of the following features:
    • Do not store the trucks within 50 ft of a required fire wall or automatic sprinkler risers.
    • Provide automatic sprinkler protection in accordance with NFPA 13, NFPA 52 and/or NFPA 58.
    • Close the fuel supply valve from the cylinder to the engine while parked in the designated storage area.
  • Refuel trucks having permanently mounted LPG or CNG fuel cylinders, and refill detachable cylinders, preferably outdoors at least 50 ft. (15 m) away from important buildings/structures.
  • Detachable LPG and CNG fuel cylinders may be exchanged indoors at least 20 ft. (6.0 m) away from open flames or other ignition sources if, prior to disconnecting the empty tank, the fuel supply is shut off at the tank and the engine is operated until all fuel in the system is consumed.
  • Use steel cylinders for LPG powered lift trucks.
  • Do not expose gas-powered (LPG, CNG or H2) trucks to high temperatures (i.e., near ovens, furnaces, or other sources of high temperature) except for extremely short intervals. Never leave lift trucks unattended near ovens and furnaces.

Hazardous (Classified) Locations:

As per NFPA 505, locations shall be classified in accordance with NFPA 70.

  • A permanent label should be present on all lift trucks that are rated for hazardous (classified) locations to indicate that special safeguards have been provided.

Class I, Division 1 Areas – these are locations in which explosive concentrations of flammable gas or vapor may exist under normal operating conditions, or where accidental release of hazardous concentrations of such materials may occur simultaneously with failure of electrical equipment.

Groups A, B, and C: Lift trucks are not permitted to be used in Class I, Division 1, Groups A, B, or C locations unless listed or approved as being suitable for use in hazardous (classified) locations.

Group D: Lift trucks designated as Type DX or Type EX, and listed or approved power operated industrial trucks determined to be suitable for the hazardous (classified) location, are permitted to be used.

Class I, Division 2 Areas – these are locations in which ignitable liquid or flammable gas is handled in closed systems or containers from which they can escape only by accident, or locations in which hazardous concentrations are normally prevented by positive mechanical ventilation

Group A: Lift trucks designated as Type DY, DX, EE, or EX, when approved for use in the hazardous (classified) location, and listed or approved power operated industrial trucks determined to be suitable for the hazardous (classified) location, are permitted to be used.

Groups B and C: Lift trucks designated as Type CNS, DS, DY, DX, ES, EE, EX, GS, LPS, GS/CNS, or GS/LPS, when approved for use in the hazardous (classified) location, and lift trucks listed or approved as being suitable for the hazardous (classified) location, are permitted to be used.

Group D: Lift trucks designated as Type CNS, DS, ES, GS, LPS, GS/CNS, or GS/LPS, when approved for use in the hazardous (classified) location, lift trucks designated as Type DY, DX, EE, or EX, and lift trucks listed or approved as being suitable for use in the hazardous (classified) locations, are permitted to be used.

Class II, Division 1 Areas – Locations in which explosive mixtures of combustible dust may be present in the air under normal operating conditions, or where mechanical failure of equipment might cause such mixtures to be produced simultaneously with arcing or sparking of electrical equipment, or in which electrically conductive dust may be present

Group E: Lift trucks designated as Type DX or EX, when approved for use in the hazardous (classified) location, and lift trucks listed or approved as being suitable for use in the hazardous (classified) locations, are permitted to be used.

Groups F and G: Lift trucks designated as Type DX or EX, and lift trucks listed or approved as being suitable for use in the hazardous (classified) locations, are permitted to be used.

Class II, Division 2 Areas – Locations in which explosive mixtures of combustible dust are not normally present or likely to be thrown into suspension through the normal operation of equipment, but where deposits of such dust may interfere with the dissipation of heat from electrical equipment, or where such deposits may be ignited by arcing or sparks from electrical equipment

Group E: Lift trucks designated as Type DX or EX, when approved for use in the hazardous (classified) location, and lift trucks listed as being suitable for use in the hazardous (classified) locations, are permitted to be used.

Groups F and G: Lift trucks designated as Type CNS, DS, ES, GS, LPS, GS/CNS, or GS/LPS, when approved for use in the hazardous (classified) location, lift trucks designated as Type DY, DX, EE, or EX, and lift trucks listed as being suitable for use in the hazardous (classified) locations, are permitted to be used.

Class III, Division 1 Areas – Locations in which easily ignitable fibers or materials producing combustible brands are handled, manufactured, or used

Lift trucks designated as Type DX or EX, when approved for use in the hazardous (classified) location, lift trucks designated as Type DY, DX, EE, or EX, and power-operated industrial trucks listed as being suitable for use in the hazardous (classified) locations, are permitted to be used.

Class III, Division 2 Areas – Locations in which easily ignitable fibers are stored or handled (except in process of manufacture)

Lift trucks designated as Type E, when approved for use in the hazardous (classified) location, power-operated industrial trucks designated as Type CNS, DS, DY, DX, ES, EE, EX, GS, LPS, GS/CNS, or GS/LPS, and lift trucks listed as being suitable for use in the hazardous (classified) location, are permitted to be used.

FM Approved Lift Trucks

FM Global approves four types of battery-powered (E, ES, EE, EX) lift trucks, two types of gasoline-powered (G, GS) lift trucks, three types of diesel-powered (D, DS, DY) lift trucks and two types of LPG-powered (LP and LPS) lift trucks.

If you would like further information regarding choosing the correct lift trucks for hazardous (classified) areas and recommendations for associated hazards, please contact Risk Logic Inc.

References:
NFPA 505, Fire Safety Standard for Powered Industrial Trucks Including Type Designations, Areas of Use, Conversions, Maintenance, and Operations
NFPA 70, National Electrical Code
FM Global Property Loss Prevention Data Sheet 7-39, Lift Trucks