A silica control plan is the document a regulator asks for first. For high-risk crystalline silica work it is not optional paperwork. It is the written demonstration that you have identified the hazard, applied the hierarchy of controls, and put monitoring in place. This is what a defensible one contains, and how to stop it going stale.
When you need one
Across the Australian model WHS jurisdictions, high-risk crystalline silica work triggers a silica control plan obligation. The specifics are set out in each jurisdiction’s guidance, for example the Managing respirable crystalline silica dust Code of Practice 2022 (Qld), yet the shape is consistent nationally, reinforced by the national prohibition on engineered stone that took effect on 1 July 2024.
If you are creating a chemical exposure assessment for a product containing respirable crystalline silica, assume you need a control plan.
The elements a plan must cover
A control plan that survives scrutiny addresses each of the following:
1. The work and the workers
- A description of the crystalline silica work being carried out.
- The tasks, materials, and processes that generate respirable dust.
- The workers (or similar-exposure groups) who may be exposed.
2. The hazard, assessed
- The exposure assessment: how much respirable crystalline silica, measured against the workplace exposure standard of 0.05 mg/m³ (8-hour TWA).
- The basis of the assessment: air monitoring data, not guesswork.
3. Controls, in order of the hierarchy
- Elimination and substitution first: can the silica work be avoided or a lower-silica material used?
- Engineering controls: on-tool water suppression, local exhaust ventilation, enclosure.
- Administrative controls: rotation, exclusion zones, housekeeping that never uses dry sweeping or compressed air.
- Respiratory protective equipment: selected, fit-tested, and maintained under AS/NZS 1715:2009. RPE is the last line, not the plan.
4. Air monitoring
- What is monitored, how often, and by whom.
- The trigger for re-monitoring and for reviewing controls when a result approaches or exceeds the exposure standard.
5. Health monitoring
- Who is in scope for health monitoring, and the baseline-plus-periodic schedule.
- The registered medical practitioner supervising it.
- How results feed back into the review of controls, without the plan ever holding clinical detail it should not.
6. Review triggers
- The events that force a review: a new task, a changed material, an exceedance, an incident, or a set review interval.
Why most control plans fail: they go stale
The elements above are well understood. The failure mode is almost never writing the plan; it is that the plan is a Word file that describes a control regime as it was on the day it was signed. Six months later the tasks have changed, an air-monitoring result has crept up, and three fit tests have lapsed, and the document says none of that.
A control plan is only as good as its connection to live records. That is the difference between a plan and a PDF.
Keeping the plan live
This is where treating obligations as data changes the picture. When your control plan is connected to the records that should drive its review:
- Creating the exposure assessment raises the control-plan obligation, so the plan is a consequence of the hazard being recorded, not a separate memory task.
- An air-monitoring result above the exposure standard fires a health-monitoring obligation and a controls review, automatically, with the citation attached.
- An approaching fit-test date raises a renewal before it lapses, so the “RPE maintained under AS/NZS 1715:2009” line in your plan stays true.
None of this replaces the duty-holder’s judgement. The plan is still yours; the controls are still your decision. What changes is that the plan stops being a static artifact and becomes the visible surface of a set of live, cited obligations, the ones a regulator is actually going to ask about.
Checklist
Use this to sanity-check any silica control plan. A defensible plan:
- Describes the silica work, tasks, materials, and exposed workers.
- States the exposure assessment against 0.05 mg/m³ (8-hour TWA).
- Applies the full hierarchy of controls, with RPE last.
- Specifies air monitoring frequency and re-monitoring triggers.
- Names the health-monitoring scope, schedule, and supervising practitioner.
- Defines the review triggers, and is actually wired to them.