How to Read a Concrete Docket (Before It Costs You)

Every agi that backs up to your hopper comes with a piece of paper, and most blokes on site treat it like junk mail. Learning how to read a concrete docket takes thirty seconds a load. Not reading it has cost operators rebuilt booms, failed slabs and month-long arguments about who pays. The docket is the load's birth certificate. Read it before the concrete moves.

What's actually on it

The mix code and strength grade, N25, N32, S40, tells you what was ordered and what class of concrete it is. N is normal class, off the standard menu. S is special class, a mix designed for that job, which usually means an engineer somewhere cares a lot about it. The ordered slump is on there, along with the maximum aggregate size. Quantity in cubes. The plant it came from, the truck number, and the customer and site details.

Then the one most people skip: the batch time. The minute that concrete was loaded. That's the clock that matters more than any other number on the page.

The 90-minute clock

The rule of thumb across the industry, and it's built into the Australian standard, is that concrete should be discharged within about 90 minutes of batching. Retarders and cool weather buy time. A 38-degree February afternoon takes it away. If the docket says the load was batched at 9:10 and it's now 11:00 because the truck sat behind a crane lift, you're not pumping fresh concrete anymore. You're pumping a decision.

Check the batch time at the window. Every truck. Before the chute swings over your hopper. It's the fastest read on whether the load in front of you is concrete or trouble.

Aggregate size and your line

The docket tells you the stone size. Your line size tells you whether that stone fits. If the job's running a small rubber line and the docket says 20mm, stop right there. That mismatch is a blockage with paperwork. Cheaper to sort it on the phone before the pour than at the reducer halfway through it.

Water goes on the docket, always

Any water added on site gets recorded on the docket and signed for. That signature is not admin. That signature is who wears it when the slab tests low at 28 days. If the builder wants water past the allowance, that's his call to sign. Not yours, not your line hand's. The same discipline that Module 02, Know Your Real Rate, drills into you for money applies here: numbers on paper protect you, numbers in your head protect nobody.

Keep every docket

Dockets are your evidence. Cubes pumped, times on site, waiting time, what turned up versus what was ordered. When the invoice gets argued in three weeks, the bloke with the dockets wins the conversation. Photograph them, keep them with the job, and don't hand your only copy to someone else's foreman.

Thirty seconds a truck. That's the whole habit. The docket already knows how your day is going to go. You just have to read it.