I Have Already Approved This Wick Size — Do I Really Need to Repeat Testing Every Time I Receive a New Production Lot?

What your original approval actually proved

When you approved a wick size, you burned candles made with wicks from one particular production lot, in your jar, wax and fragrance, and they performed well. That result is valuable, but its reach is limited. It tells you that the design of the wick suits your candle. It cannot tell you that every future lot will be built to that design with the same fibres, braid tension and treatment. Wick manufacturing, like any manufacturing, varies from run to run, and a supplier may change a raw material without changing the product name.

That said, full revalidation on every delivery is wasteful. If you ran a complete burn-to-end matrix each time 500 wicks arrived, testing would eat your margin and your calendar. The honest answer to the question is: no, you do not need to repeat full qualification for every lot, but you do need a short, fixed goods-in check every time, and clear triggers that escalate to fuller testing. Skipping checks entirely is how a slow drift in wick construction becomes a returns problem months later.

Think of it as three tiers: a quick check every time, a comparison burn when something is new or different, and a full qualification only when the evidence says you need one.

A three-tier routine for approved wicks

The tiers are a suggested starting point. A business pouring 50 candles a month and one pouring 5,000 will reasonably set the Tier 1 sample and the Tier 2 triggers differently. What matters is that the rule is written before the delivery arrives, so the decision is not made by whoever happens to be in a hurry that day.

What the every-lot check looks like in practice

Choose the comparison candle carefully. It should be the product where a wick difference would show first and cost most: usually your widest jar, or the fragrance you pour at the highest load, or simply the candle you sell most of. Keep that choice fixed from lot to lot, so each new record lines up with the last. Run the comparison in the same room you normally test in, and note the room temperature on the sheet. A cool December evening and a humid monsoon afternoon can shift how a pool develops, and without the retained control burning beside the new wick you could blame the lot for something the weather did. With the control there, any seasonal effect applies to both candles equally.

Worked example: cost of checking versus cost of a bad lot

Say your bestseller is a 135 g candle in a CSI 135 g tin, made with Luxury Soy Wax CSI 464 and British Rose at 8% of total candle weight, with an Eco Candle Wick, Thin (C1). The load convention gives 135 × 0.08 = 10.8 g of oil and 135 − 10.8 = 124.2 g of wax.

A Tier 1 comparison uses two candles: 2 × ₹198.81 = ₹397.62 in materials, plus about half an hour of inspection and one attended burn session. If a lot of 1,000 wicks goes into 1,000 tins without a check and turns out to burn differently, the material at stake is 1,000 × ₹198.81 = ₹1,98,810.00, before labels, boxes, labour or a single unhappy customer.

The every-lot check costs about 0.2% of what it protects. That is why skipping it is false economy. Equally, running a full Tier 3 requalification on every lot would multiply the testing cost many times over for very little extra certainty when the lots keep matching. The tiered routine puts the money where the risk is.

One extra point on this example: the product page for British Rose states a flashpoint of 192°C and 0% vanillin, so colour drift in the wax is unlikely to confuse a wick comparison. If your bestseller used a vanillin-bearing oil, you would note colour separately so it is not mistaken for a wick effect.

Triggers that move you up a tier

Write the triggers down and keep them next to the goods-in bench. When one fires, the lot stays in quarantine until the higher tier is complete. The list below is a suggested starting point; add triggers that match your own history.

When a lot is escalated, tell the supplier and ask a specific question: has anything changed in the fibre, braid or treatment? For CSI wicks, message +91 7397976926 on WhatsApp. CSI does not publish wick dimensions, tolerances or lot-change notices, so your own retained wicks and records are the evidence, and whatever answer you receive belongs in the lot file. If the approved wick stops matching your candles, the lot stays in quarantine regardless of who supplied it, including us. Do not quietly rewick your formula around a lot that drifted; either requalify properly or wait for material that matches.

Where this page fits

CSI already has guides that cover parts of this question. This page covers the goods-in check for the question above; these go deeper on the rest:

Three things to buy for this job

Frequently asked questions