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Why Do Our Contamination Deductions on Incoming Loads Depend on Who Is on the Weighbridge?

Recycling sites apply contamination deductions to supplier loads unevenly. We build deduction rules, photos at tipping and a quality history per supplier.

Updated 3 min readBy SpiderHunts Technologies

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Quick answer — TL;DR

Deductions vary because each operator judges contamination by eye and records it as a number on a ticket, with no shared rule, no photo and no history of that supplier's loads. We build deduction rules by grade, a tipping inspection step with photos, a record per supplier over time, and a way to share evidence with suppliers when they query a deduction.

Two operators, two deductions

A supplier delivers baled cardboard every week. On Monday, one weighbridge operator inspects the tipped load, sees some plastic strapping and wet bales, and writes a deduction on the ticket. On Thursday, a different operator sees a similar load and deducts half as much. The following Monday, the first operator is on holiday and nobody deducts anything.

The supplier's manager notices. She rings your sales manager, asks why Monday's deduction was so high when Thursday's was lower, and wants evidence. There is none. Your sales manager reduces the Monday deduction to keep the peace.

Meanwhile, the contamination still has to go somewhere. It is picked out on your line or goes out as residue, and you pay for both.

Why deductions are inconsistent

Contamination is judged by eye, and each operator's eye is different.

  • There is no written rule for how much to deduct for what.
  • Deductions are recorded as a number, without a photo or reason.
  • Operators do not see a supplier's history, so each load is judged alone.
  • Suppliers query deductions and there is no evidence to show.
  • Deductions are reduced to keep suppliers happy, so the rule becomes meaningless.

What you deduct, and on what basis, is your commercial arrangement with each supplier. We make the process consistent and recorded.

What inconsistent deductions cost

Under-deducting means paying for contamination you then pay again to remove. Over-deducting, or deducting inconsistently, damages supplier relationships and invites challenges that end with you giving money back.

Without a history, you cannot tell which suppliers are genuinely improving, which are getting worse, and which need a conversation about their segregation. You cannot give good suppliers credit for being good.

Operators feel it too. Nobody likes being the one who deducted hard on Monday and then got overruled by the office. After a few of those calls, operators stop deducting at all, because it is easier, and the problem quietly grows.

How we make deductions consistent

What we build gives operators rules and a quick way to record what they see.

  1. Deduction rules are set per grade: what counts as contamination, the bands you use, and the deduction for each band. The rules are yours.
  2. At tipping, the operator records the inspection on a tablet, picking the contamination type and band, and taking photos of the load.
  3. The deduction is calculated from the rule, and the operator can adjust it with a reason, which is recorded.
  4. The ticket shows the deduction, reason and a reference to the photos.
  5. Each supplier's history shows deductions over time, with photos, so operators see whether this load is unusual.
  6. Suppliers querying a deduction can be sent the photos and rule, or see them on a simple portal.
BandExampleDeduction
CleanWithin specificationNone
MinorSome strapping or filmYour minor rate
ModerateVisible mixed material, some wet balesYour moderate rate
RejectedOutside what you acceptLoad refused or charged under your terms

Monday and Thursday with rules

On Monday the operator records the cardboard load as minor contamination, with photos of the strapping. The deduction follows the rule. On Thursday a different operator sees a similar load, records the same band, and the same rule applies.

When the supplier's manager queries a deduction, your sales manager sends her the photos and the rule. She sees the strapping and speaks to her own warehouse team. The following month, the supplier's history shows fewer deductions.

Do deductions depend on who is weighing?

  • Different operators deduct differently for similar loads.
  • Deductions are a number on a ticket with no photo.
  • Suppliers query deductions and you cannot show evidence.
  • Deductions are often reduced to avoid arguments.
  • You cannot see a supplier's contamination history.

FAQ

Frequently asked questions

The questions readers ask us after this guide.

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Do you set the deduction rates?

No. The rules and rates are your commercial decisions. We apply them consistently.

Can operators still use their judgement?

Yes. They pick the band and can adjust with a reason. The reason is recorded.

Does this slow down the weighbridge?

Inspection is at tipping, not on the weighbridge, and takes a few taps and photos.

Can suppliers see their history?

Yes, if you want. A portal can show each supplier their loads, deductions and photos.

What do you need from us?

Your grades, how you deduct now, and a few recent deduction disputes.

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