Where Should Prohibition Signs Be Installed?

Quick answer

Install prohibition signs at entrances to controlled areas, at the start of pathways to hazards, at decision points where a person chooses to proceed, on or immediately adjacent to the equipment involved, and anywhere a banned action might otherwise occur without clear visual cues.

Understanding prohibition signs

Prohibition signs are designed to stop an action. They typically use a simple pictogram with a red circle and diagonal bar, often accompanied by brief text. The design works quickly at a glance, which is critical when a person is moving, using equipment or approaching a risk area.

Their effectiveness depends more on location and clarity than on size alone. A well-placed smaller sign will outperform a large sign that appears too late or is hidden by clutter.

In Australia, workplace prohibition signs should follow AS 1319, using a red annulus and diagonal bar over a black symbol on a white field, with optional black text below. For typical viewing distances, practical sizes are 300 × 225 mm for doors and machinery interfaces, 450 × 300 mm for corridors and small gates, and 600 × 450 mm (or larger) for vehicle approaches or long sightlines. Where signs are road-adjacent or require night visibility, consider reflective substrates that meet AS/NZS 1906.1 classes, noting glare and environment.

Placement principles

Use these principles to decide precise locations on your site:

• Before the action happens: The sign must be visible prior to a person committing to the prohibited action (e.g. before stepping through a doorway).
• In the line of sight: Position within natural eye lines where people look as they approach: door handles, gate latches, machine controls, or walkway entries.
• At decision points: Place signs where a person chooses whether to enter, proceed, smoke, operate, or touch.
• Repeated in long approaches: On long corridors or routes, repeat signs to maintain visibility, especially near forks or intersections.

Entry and approach

Mount “No entry” and other access-related prohibitions at site gates, building entrances, restricted room doors and the first point along an approach path where entry could be attempted.

• Site gates and perimeter fences
• Building and plant room doors
• Vehicle access points to depots, yards or loading docks

At the hazard

Where the prohibited action relates to a specific hazard, place the sign at or beside that hazard so the message is unmistakably linked.

• On tank doors or guards for “Do not open” or “Do not operate”
• Beside energised switchboards for “Unauthorised access prohibited”
• At chemical stores for “No smoking”

Interfaces and equipment

People focus on controls. Position prohibition signs at machine interfaces and control stations where hands and eyes already go.

• Next to stop/start buttons or key switches
• On covers, hatches and isolation points
• On touch screens where software actions are restricted

Shared spaces

In break areas, loading zones and car parks, target the behaviours most likely to occur in those zones.

• “No smoking” signs in outdoor seated areas or near building air intakes
• “No parking” signs in loading bays
• “No pedestrian access” at forklift-only aisles

Field notes from Sign Portal installations: relocating “No Pedestrian Access” from a wall to a bollard line at a loading dock immediately intercepted foot traffic at the pinch point; adding a second “No Smoking” at bench eye-level in a break area reduced ash accumulation around door thresholds observed during follow-up audits.

Line of sight and visibility

Keep signs free of obstructions and visual noise. If a sign competes with posters, notices or product displays, relocate or declutter so the prohibition stands out.

Choose a size and placement that suits the viewing distance and speed of approach. For example, a pedestrian approaching a door will notice a smaller sign than a driver approaching a yard gate.

• Mount near eye height for the intended audience and task.
• Angle slightly towards the approach path rather than parallel to walls when needed.
• Ensure lighting is adequate by day and night where relevant.

Practical size guide used by our installers: 300 × 225 mm for doors within 3–5 m; 450 × 300 mm for corridors and approaches up to 10 m; 600 × 450 mm or larger for vehicle gates or approaches beyond 10 m. Where drivers must read supplementary text, increase size or duplicate the sign at driver eye height.

Materials for different environments

Material choice affects durability and how easy it is to mount the sign in a given environment. Common options include rigid panels for long-term fixtures and adhesive labels for equipment and smooth surfaces.

• Aluminium composite panel (ACP): Rigid, lightweight and suited to outdoor gates, fences and walls. Works well with direct UV printing.
• Self-adhesive vinyl labels: Ideal for machine housings, doors and glass. Can be contour-cut for neat placement near controls.
• Corflute (fluted polypropylene): Best for temporary controls such as short-term site access restrictions.
• Acrylic or polycarbonate: Clear or coloured rigid sheets for indoor environments where a premium appearance is preferred.

Sign Portal material notes: we specify AS 2700 R13 Signal Red for the annulus/bar and black symbols on matte white backgrounds for reduced glare. For high-abuse zones, we add a hard-wearing clear overlaminate (anti-graffiti option available). In washdown areas, labels are edge-sealed to resist water ingress.

Mounting methods

Choose fixings that suit the surface, environment and the expected lifespan of the control.

• Walls and doors: Screws with wall plugs for masonry; screws into studs or suitable anchors for framed walls; VHB tape for smooth, clean, indoor surfaces.
• Fences and mesh: Cable ties or stainless fixings through pre-drilled panel holes.
• Glass: Adhesive vinyl (front or reverse-applied) or clear acrylic panels with discreet mounts.
• Machinery: Adhesive labels on clean, degreased surfaces; mechanical fasteners where vibration is high.
• Posts and frames: Post-mounted sign blanks or A-frames for mobile placement.

Installer tips from our team: lightly round ACP panel corners (2–3 mm radius) to minimise snagging; use corrosion-resistant fixings near the coast; for VHB mounting, use isopropyl alcohol to clean, apply a primer to low-surface-energy substrates, then press with firm, even pressure. For ACP into thin sheet metal, target 2–3 Nm torque to avoid crushing the core.

Australian conditions to consider

Australia’s climate can be harsh on signage. High UV, heat, coastal salt and wind exposure all influence material and fixing choices.

• Sun and heat: Use UV-stable inks and substrates that resist warping. Consider rigid panels for exposed facades.
• Coastal environments: Prefer corrosion-resistant fixings and substrates. Rinse salt-prone surfaces during maintenance checks.
• Tropical rain and humidity: Ensure edges are sealed and fixings do not trap water against substrates.
• Wind load: On fences and posts, use adequate fixings and avoid oversize panels that can act as sails.

At Sign Portal, rigid safety signs are commonly direct-printed on our UV flatbed printers to ACP, then cut to size and drilled as required on our CNC router. Labels are produced on a wide-format printer/cutter for contour accuracy around text or pictograms. These processes support consistent colour and clear graphics suited to safety-critical messages.

Quality and compliance at Sign Portal: artwork is checked against AS 1319 layout conventions, colours are referenced to AS 2700, and mounting hole patterns are CNC-cut for repeatable installs. Our installers hold White Cards for site access and follow documented SWMS for ladder, EWP and live-site works where required.

Common mistakes and how to avoid them

• Too late in the journey: Signs placed after a barrier or action point are frequently missed. Move them upstream to the decision point.
• Competing messages: Pinboards and marketing posters can drown out a critical prohibition. Separate safety from promotional content.
• Poor contrast or glare: Gloss glare from downlights or windows can make symbols hard to see. Adjust angle or finish.
• Blocked lines of sight: Open doors, stacked pallets or new fixtures can hide signs. Audit after layout changes.
• Wear and fade: Scratched or faded signs reduce credibility and compliance. Replace when legibility drops.

Planning, auditing and maintenance

Build a simple plan so placement remains effective over time.

1. Map critical decision points: Mark entries, approaches, controls and high-risk behaviours on a simple floor or site plan.
2. Select materials for each zone: Match permanent or temporary substrates to conditions (indoor, outdoor, washdown, coastal).
3. Install and verify: After fitting, walk the route like a first-time visitor. Adjust angles and heights where signs do not immediately catch the eye.
4. Inspect routinely: Add signage checks to monthly or quarterly WHS inspections, including fixings, legibility and obstructions.
5. Document replacements: Keep a record of sizes, materials and mounting so you can reorder quickly.

Repairing, refurbishing and replacing signs

Not every failed sign needs full replacement. Use these repair pathways to extend service life while keeping compliance tight:

• Loose or rattling panels: Replace missing fixings and add nylon spacers or larger backing washers on mesh to spread load. Re-torque fixings after 24 hours.
• Adhesive label edge-lift: Clean with isopropyl alcohol, warm gently, trim frayed edges, and apply an edge sealer. If contamination has migrated under the film, replace the label.
• Graffiti and scuffs: Use citrus-based remover or isopropyl alcohol on matte-laminated faces. For persistent tags, specify anti-graffiti laminate at the next refresh.
• Faded inks or chalking: UV exposure beyond design life warrants replacement. Photograph, document size/substrate, and reorder to the same spec.
• Relocation after layout changes: If line-of-sight is now blocked, relocate and mechanically fix in the new location; fill previous holes to prevent corrosion and record the change in your sign schedule.
• Non-compliant artwork: Replace legacy symbols/text that don’t align with AS 1319. Sign Portal can update your artwork archive and supply revised signs matched to your existing hole patterns.

Documenting and reordering

Keep a sign schedule that lists each prohibition sign’s location, wording or pictogram, size, substrate and fixing method. Photographs taken square-on help future reorders match exactly.

Sign Portal supports repeat orders and customer-specific catalogues, helping trade teams reorder frequently used safety signs without re-measuring. Australia-wide delivery, including regional and remote areas, is available.

Sign placement checklist

Use this quick checklist on site. Tick items as you go.

• Decision point identified and marked on plan
• Line-of-sight verified from typical approach angles
• Correct sign type per AS 1319 (prohibition symbol + optional text)
• Size matched to viewing distance (300 × 225 / 450 × 300 / 600 × 450+)
• Height set to eye line of intended audience (or driver eye height)
• Mounting method suits surface and environment
• Fixings corrosion-resistant where applicable
• Clutter removed; competing messages relocated
• Lighting adequate; glare checked and mitigated
• Repeaters added on long approaches and at forks
• Photograph installed sign and update sign schedule
• Inspection interval added to WHS checklist
• Repair pathway noted (spares, edge sealer, cleaning products on hand)

Order prohibition signs online

Ready to install or refresh? Order standard and custom prohibition signs from Sign Portal:

• Prohibition signs — AS 1319-compliant symbols and text options
• No Entry signs — site gates, restricted rooms and hoardings
• No Smoking signs — indoor/outdoor, anti-graffiti laminate available
• Custom prohibition signs — your wording, sizes, hole patterns and material

Need a placement audit or bulk rollout? Our team can map decision points, produce site-specific schedules and kit signs by area to speed installation.

Who is responsible for placement?

Ultimately, the duty holder for the workplace or site should approve placement in line with their risk assessments and operating procedures. Consult supervisors, WHS advisors and those who work in the area — they often know where eyes go and where behaviours occur.

Summary

Place prohibition signs so they intercept behaviour at the right moment: before entry, before operation and where attention naturally falls. Choose materials that match the environment, mount them securely, keep lines of sight clear and audit regularly. Good placement turns a simple red circle and slash into an effective control.

Related Sign Portal resources: Prohibition - Do Not Wear Gloves Sign · Prohibition - No Entry Sign · Prohibition General - No Smoking Except In Designated Areas Sign