How to Read a Traffic Guidance Scheme: Symbols, Distances and Tapers

To read a TGS, start with the title block and notes (plan number, revision, location, speed, hours of use), then study the road layout, then follow each approach in the direction traffic travels: advance warning signs, taper, buffer, work area and termination. Use the legend for symbols and take distances from the plan and its referenced standard.

A traffic guidance scheme packs a lot of information onto one page. Experienced crew leaders read it the same way every time so nothing gets missed. This guide shows you that method, explains the common symbols and zones, and lists the checks to make before you put a single cone on the road. It is general guidance only: TGSs vary between designers and states, and a TGS must be prepared by a suitably qualified person.

If you're new to the topic, start with what a traffic guidance scheme is.

Step 1: Read the title block and notes first

Before looking at the drawing, read the boxes around it. This is where most avoidable mistakes start: the layout is fine, but it's the wrong layout for today.

Check:

• Plan number and revision. Is this the current approved revision? Does it match the one referenced in the permit, the traffic management plan and the SWMS?
• Location. Street name, suburb, chainage or nearest cross street, and which side of the road.
• Speed. The existing speed limit and any temporary speed limit the plan applies.
• Hours and days of use. Day only, night only, outside peak, weekends.
• Conditions of use. For example "only where traffic volumes are low", "no work within the intersection", "TMA required", or "pedestrian route to be maintained at all times".
• Designer details. Who prepared it and their qualification, plus any approval references.
• Standard referenced. Which standard or guide the plan was designed to, such as the Austroads Guide to Temporary Traffic Management with state supplements, AS 1742.3, or in NSW the TS 05492:1.0 standard that replaced the TCAWS manual on 25 June 2026.

Step 2: Understand the road layout and orientation

Next, get your bearings:

• Find the north arrow and match it to the real street. Many set-up errors come from reading a plan upside down.
• Identify each direction of travel and the number of lanes.
• Note intersections, driveways, bus stops, bike lanes, pedestrian crossings and kerb ramps shown on the plan, and look for any that exist on site but aren't drawn.
• Locate the work area and the footprint of plant and trucks.

Then picture yourself as a driver approaching from each direction. That's how you should read the rest of the drawing.

Step 3: Follow each approach through the work zone

Most TGSs are built from the same zones. Work through them in the order a driver meets them.

On a two-way road you'll do this twice, once for each direction. Plans for intersections and multi-lane roads may show several approaches, each with its own sign sequence.

Common symbols on a traffic guidance scheme

Symbols differ slightly between designers, so always use the legend on the plan first. Typical symbols include:

• Signs: drawn as a small rectangle or diamond on a post or stand, usually labelled with a sign code from the applicable standard or state sign catalogue, sometimes with the sign face shown. A note may say whether the sign is on one or both sides of the road.
• Cones and bollards: a line of small circles or triangles, often with spacing noted.
• Barriers: a solid or hatched line for safety barriers or water-filled barriers, sometimes with end treatments shown.
• Arrow boards and VMS: a rectangle with an arrow, or labelled as a variable message sign with the message noted.
• Traffic controllers: a person symbol, often marked as a stop/slow position, with notes about sight distance or radio contact.
• Portable traffic signals: a signal head symbol with the stop line position.
• Truck-mounted attenuator (TMA): a vehicle symbol, usually labelled TMA, placed behind the work area or a mobile works vehicle. Our guide to the truck-mounted attenuator explains when one is required.
• Work vehicle and plant: vehicle outlines showing where trucks, excavators or cranes sit.
• Hatching or shading: the work area or a closed lane.
• Arrows: direction of travel and the path traffic is guided along.

If you meet a symbol that isn't in the legend and you can't identify it with certainty, ask before you set out.

Reading distances, tapers and buffers

This is the section people most often want simplified into a rule of thumb. Don't. The sign spacing, taper lengths and buffer lengths on a TGS come from the plan and the tables in the applicable standard or guide, based on the road's speed, layout and conditions. A suitably qualified designer works them out. Your job on site is to read them correctly and achieve them.

How plans show distances:

• Written distances. The actual distance in metres between items, written on the drawing.
• Letter labels. Many plans use a letter (for example a "D" between signs) that refers to a table in the notes or in the referenced standard. Find that table and confirm which speed row applies.
• Taper descriptions. The taper may be labelled by type, such as merge, shift, shoulder or termination, with a length or a reference.
• Not to scale. Most TGSs are diagrams, not survey drawings. Measure distances on the road; never scale them off the page.

Tips from the field:

• Measure using a measuring wheel or known reference points, not paces, especially at night.
• Where a driveway, intersection or bend prevents a sign going exactly where shown, check whether the plan's notes allow an adjustment. If they don't, the plan needs revising by the designer.
• Sight distance matters as much as spacing. A sign behind a parked truck or a tree isn't doing its job.
• Device spacing in tapers is usually tighter than along the work area. Follow what's shown.

Step 4: Check the notes for set-up and removal order

Some plans include a set-up sequence; many rely on the crew's training. The usual principle is to install in the order a driver will meet things, starting with the furthest advance warning sign, so drivers are always warned before they reach something new. Removal goes in reverse, so warning signs are the last things to come out. Look for notes about:

• Covering permanent signs that conflict with the layout (for example permanent speed limit signs inside a temporary speed zone).
• When the temporary speed limit signs go up and come down.
• Where the work vehicle or TMA must be during set-up and pack-down.
• Escape routes and where controllers stand relative to traffic.

Step 5: Compare the plan with the real site

Walk or drive the site with the TGS in hand before set-up. Ask:

• Does every road feature on the plan exist, and is there anything on site that isn't on the plan?
• Can every sign be placed where shown and be seen?
• Can the taper and buffer lengths actually be achieved?
• Is the pedestrian route usable, including for a wheelchair or pram?
• Are there new hazards: a school pick-up, an event, road surface damage, roadworks by others nearby?

If the answer to any of these is a problem, stop and get advice. A TGS that doesn't fit the site needs to be revised by a suitably qualified person, and any approved on-site adjustment needs to be recorded. In NSW, crew who set out and check layouts hold the Implement Traffic Control Plans (ITCP) qualification, and inspections are recorded at the start and end of each shift and at suitable intervals during it.

Quick TGS reading checklist

Print this and keep it with the plans:

1. Plan number and revision match the permit, TMP and SWMS.
2. Location, side of road and direction of travel confirmed.
3. Speed (existing and temporary) noted.
4. Hours, days and conditions of use allow today's work.
5. Legend read; every symbol identified.
6. Each approach traced: signs, spacing, taper, buffer, work area, termination.
7. Distances confirmed from the plan or its referenced table for the correct speed.
8. Pedestrian and cyclist route understood.
9. Equipment count matches the plan, plus spares and sign covers.
10. Site walked; any mismatch raised before set-up.

The traffic control pre-start checklist builds these checks into the daily crew briefing, and our comparison of the traffic management plan vs TGS explains how the TGS fits the wider plan.

Where to check the standards

The national reference is the Austroads Guide to Temporary Traffic Management, available via austroads.gov.au. AS 1742.3 covers traffic control devices for works on roads and is published through Standards Australia. In NSW, check the current requirements with Transport for NSW. Standards are updated, and councils or contracts may specify a particular document, so always confirm which version applies to your job.

Next steps

Reading a TGS well is a skill that improves with every set-up, so build it into your briefings and walk-throughs. If you run a traffic control company, TrafWise puts the current TGS and the pre-start in each crew member's hands before the shift starts.