When selecting a pump for hazardous areas, it is necessary to consider factors such as the classification of the hazardous area, the type of fuel, and the required capacity. A solution suitable for Zone 2 may not be suitable for Zone 1, and even pneumatic pumps or manual pumps need to be grounded. Certification, hoses, and installation are all crucial.

When does a standard transfer pump become a fire hazard?

Unlabeled oil transfer pumps may become ignition sources when operating near flammable fuel vapors. Motors, switches, plugs, and brushes may produce arcs or sparks, the pump itself may overheat, and static charges may be generated when the fuel flows through hoses and connectors. Insufficient ventilation can exacerbate the danger. Gasoline has a higher risk of flammable vapor than diesel.

Why is the fuel type important?

Gasoline has a higher volatility than diesel. Most diesel has a flash point above 55°C and is safer under normal conditions, but the situation changes when heated, mixed with gasoline, or in spray form. Choosing a pump based solely on the label is not enough; fuel temperature and flammability must also be considered. The fuel label only indicates that it is designed for a specific hazardous area and does not mean it is suitable for all places.

What factors make a pump suitable for hazardous areas?

The pump must be designed and certified for the specific hazardous area, including the motor and electrical enclosure, which must meet the requirements of gas groups and temperature classes. A complete transfer system is also important – hoses, nozzles, connectors, switches, storage tanks, and pipes may all increase the risk of fire. Even certified pumps can still be dangerous if installed improperly or if equipment that generates static electricity is connected.

Why must the certification match the location?

Pumps certified for Zone 2 cannot be used in Zone 1, and gas groups and temperature classes are also relevant. ATEX certification involves the certification of explosion-proof equipment within the European framework, while IECEx proves compliance with international standards. Neither can replace the actual rated value of the equipment. When choosing a pump for a Zone 1 transfer, ensure that the pump and accessories have been certified for Zone 1. When there is uncertainty about the classification of the area, it should be classified by qualified personnel according to local regulations.

Which motor type is best?

There is no perfect driver that completely eliminates all ignition possibilities. Consider all factors related to the entire process.

Pneumatic diaphragm pump: Replaces the motor with compressed air to eliminate the ignition possibility caused by electricity, but not all pneumatic pumps are suitable for flammable fuels. Static discharge and grounding must be addressed. It is suitable for facilities with compressed air and frequent transfers.

Explosion-proof electric pump: Suitable for fixed installations with power supply and known hazardous area classification. The certificate must correspond to the area, gas group, and temperature class. Ordinary electric diesel pumps cannot be safely used in hazardous areas.

Manual pump: Suitable for transfer volumes that are small and do not require power equipment, with no risk of electric sparks. However, static discharge or fuel spillage risks still exist. Conductive equipment, appropriate hoses, and grounding devices are still necessary. The fuel must be transferred under controlled conditions.

Match the pump to the transfer task

Consider the single transfer volume, transfer distance and height, and tank volume. The pump, hose, and nozzle must operate within their respective parameters. For handling flammable liquids, it is recommended to maintain a stable flow rate, operate the transfer pipe or nozzle near the bottom of the container to avoid splashing. Purchasing an explosion-proof pump that meets the requirements is more sensible than an uncertified high-flow pump.

Q&A

1. Does diesel require explosion-proof pumps? 

Not in all cases, but pumps operating in hazardous areas may need to be so. The classification of the area and the pump certification determine whether standard diesel pumps are acceptable.

2.Can pneumatic pumps be used in hazardous areas?

Yes, but they must be certified for specific areas and installed correctly. Pneumatic diaphragm pumps eliminate the ignition source of the motor, but static electricity remains a concern. Certification, grounding, and installation conditions must be met.

3.The cheapest and safest transfer method? 

For small batches of occasional transfers, a manual pump that suits the on-site conditions may be less costly, but conductive equipment, grounding, anti-static measures, and good ventilation are still crucial. Ordinary low-cost electric pumps or temporary plastic devices should not be used in hazardous areas.

4.Which ATEX area does the fuel storage area belong to?

It is not a single area. Depending on the tank design, steam emission points, fuel characteristics, ventilation, and operating conditions, the site may contain Zone 0, Zone 1, and Zone 2. The internal steam space of the tank may require stricter conditions, and ventilation outlets, filling points, and distribution equipment may belong to Zone 1 or Zone 2. The site should be classified by qualified personnel before selecting equipment.