Rank: New forum user 
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I am at the moment contesting several managers beliving that the discharge of electrostatic charge from a road tanker whilst loading or unloading from a silo inside a building (Non-Hazardous powder) does not pose any danger as no earthing point are being used.
Baring in mind the DESEAR and ADR regs and of course the fact that the material being used is non-haz, I still believe that the fact that electrostasticity conducted through the hoses to the tanker generated would still harness enough power to pose a risk factor and cause concern because of no earthing points used.
My question then is, Do tankers loading/offloading liquids or powders require to be connnected to an earthing point considering the materials are not hazardous ?
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Rank: Super forum user 
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A bit more clarity on what you consider non-hazardous may help
Finely divided non-hazardous materials can present their own hazards - Aluminium ingot/block/foil is non-flammable wheras the powder can ignite. Tipper delivered Potatoes present low risk - extract their starch and blow this powder from a tanker in to a silo and you have a potential explosion. Energy efficient tyres have a tendency to insulate static charge in the vehicle (Mrs Roundtuit suffered every time she exited one car we drove until its first tyre change). Amplify this by blowing a powder through a rubber or other insulated hose....(like rubbing a ballon against a jumper)
The tanker will already have earth connection points as standard so for the sake of 2 - 5 metres of cable with a clip at one end and a few seconds during connection/release? Liquids tend to naturally bridge any charge differential between tanker and silo connection point. Did have one delivery company with an earth link wound in to the outer sheath of its discharge hoses
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Rank: Super forum user
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A bit more clarity on what you consider non-hazardous may help
Finely divided non-hazardous materials can present their own hazards - Aluminium ingot/block/foil is non-flammable wheras the powder can ignite. Tipper delivered Potatoes present low risk - extract their starch and blow this powder from a tanker in to a silo and you have a potential explosion. Energy efficient tyres have a tendency to insulate static charge in the vehicle (Mrs Roundtuit suffered every time she exited one car we drove until its first tyre change). Amplify this by blowing a powder through a rubber or other insulated hose....(like rubbing a ballon against a jumper)
The tanker will already have earth connection points as standard so for the sake of 2 - 5 metres of cable with a clip at one end and a few seconds during connection/release? Liquids tend to naturally bridge any charge differential between tanker and silo connection point. Did have one delivery company with an earth link wound in to the outer sheath of its discharge hoses
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Rank: Super forum user
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If you operate a science/fact/evidence based h&s system, then unless you can find some sort of science/research paper then I think you will be struggling to convince people.
If the powder you are handling isn't covered by ADR /dangerous goods labelling & transport requirements says a lot.
I assume you have an up to date MSDS? What does that say?
You could consider taking a sample of the powder and commission a reputable science/test lab to provide a report on the powders flammability/ electro-static hazard potential - tested to a recognised standard & methodology - if you really do have serious concerns about its explosion potential and hence application of DSEAR.
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Rank: Forum user
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You do not say what the substances are that you are discharging, but powders such as icing sugar and cornstarch are not classified as hazardous and the SDSs even from reputable suppliers do not mention explosion risks, yet they can ignite. (See earlier post re: "powder runs" for an example of ignition of a powder.)
This document from the HSE para 47 advises earthing of tankers. "Safe handling of combustible dusts" http://www.hse.gov.uk/pUbns/priced/hsg103.pdf.
This may help persuade your managers.
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Rank: Super forum user
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SDS tend to describe the bulk properties of materials not what might happen to them in a particular situation, which is why you should always be wary of the SDS. They can either exaggerate the risk or understate it. ADR is about the actual transport of materials and its primary aim is to make sure that the carrier is aware of the hazards of the material that they are transporting. It does not tell them do to handle it at the delivery point. That is where DSEAR comes in. The HSE guidance quoted is very good and includes a whole load list of substances that will not have an SDS (because they are foodstuffs) which can pose an explosion risk.
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Rank: Super forum user
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Static can be generated whenever two dissimilar materials pass each other, in this case the powder passing through hoses at some speed. Without knowing more about the powder being delivered, it is difficult to say how much of an ignition risk would be caused. Powders can be coarse or fine, damp or dry. I would tend to err on the side of caution and provide some earthing, and I'm sure the guidance documents referred to in other posts would back you up.
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Rank: Super forum user 
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It's actually mor bonding than earthing, an equalisation of potential. Any "static" then generated can be safely dissiapated through the earthing system, it's no good knocking a rod into the ground @ maybe 150 Ohms, and connecting the tanker to that if the impedance to ground of the tank system is 0.01 Ohms as you will still have a difference in potential due to the difference in conductivity to ground.
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