Safety Audit & PHSR
Risk assessment, machine safeguarding design, and safety circuit implementation for industrial equipment in Ontario — engineered in-house, reviewed and signed off by an independent, arms-length safety engineer.
Ontario Regulation Ties a PHSR to the Equipment, Not Just the Industry
Under Ontario's Industrial Establishments Regulation (O. Reg. 851), a Pre-Start Health and Safety Review is generally required when new or significantly modified machinery, equipment, or processes are introduced — particularly where guards, safety controls, or other protective devices are part of the change. "Significant modification" covers more than full machine rebuilds: a guard removed and not replaced, a safety circuit altered during a retrofit, or a new tool added to an existing robot cell can all trigger the requirement.
The earlier a PHSR is considered in a project, the less it costs to satisfy — scoping the risk assessment and safeguarding design alongside the rest of the engineering avoids redesigning safety systems after the fact.
Safety Engineering, From Risk Assessment Through Implementation
Risk Assessment
Task-based hazard identification with severity, exposure, and avoidance scoring to determine risk category for every task and access point.
Safeguarding Design
Light curtain, area scanner, and physical guard placement sized to the hazard — not a generic catalog default.
Safety Circuit Design
Safety PLC, safety relay, and E-stop circuit design, validated against the safety functions the risk assessment actually calls for.
Safe Distance & Stopping Time Calculations
Robot and machine stopping time, safety device response time, and depth penetration factor calculated to size and place safeguarding correctly.
Existing System Safety Audits
Reviewing installed guarding, interlocks, and safety circuits against current standards, and flagging gaps before they become findings.
PHSR Coordination & Support
Preparing the technical package — assessments, calculations, drawings — and coordinating with an independent reviewing engineer through to sign-off.
Engineered by Us, Signed Off by an Independent Reviewer
Hazard Identification & Risk Assessment
Task-based hazard identification with severity, exposure, and avoidance scoring, producing a risk category for every task per CSA Z434.
Safeguarding Design & Calculations
Guarding type and placement determined using safe distance formulas — stopping time, safety device response time, and depth penetration factor.
Implementation
Safety circuits, light curtains, area scanners, interlocks, and guarding designed, wired, and installed to match the assessment.
Independent Review & Sign-Off
The technical package goes to an arms-length, independent safety engineer for formal PHSR review and sign-off — by design, not by us.
Closeout & Documentation
Risk assessment, calculations, drawings, and the signed PHSR delivered together as one closeout package.
Safeguarding We've Designed and Installed
What You Get
- Task-based risk assessment with hazard identification and risk category
- Safe distance and stopping-time calculations (CSA Z434)
- Safety circuit schematics and safety PLC/relay logic
- Light curtain and area scanner sizing and mounting configuration
- Updated machine guarding drawings
- Independent PHSR report with reviewing engineer sign-off
We Are Not the Reviewing Engineer
To avoid any conflict of interest, the formal Pre-Start Health and Safety Review and final sign-off is always completed by an independent, arms-length safety engineer or specialist — not by the team that designed the safeguarding. A reviewer with a stake in their own design passing isn't an independent review.
We handle the risk assessment, safeguarding design, calculations, and implementation, and we coordinate the review process — preparing the technical package the reviewing engineer needs and working through any findings. The sign-off itself comes from someone with no stake in the outcome except worker safety.
- • New or modified equipment requires a PHSR before startup (Ontario Reg. 851 — Industrial Establishments)
- • Guards, interlocks, or safety circuits were removed, altered, or bypassed
- • Existing safeguarding hasn't been reviewed against current standards
- • A risk assessment or safe-distance calculation is needed to size a light curtain or guard
Common Questions
Do you perform the PHSR sign-off yourselves?
No, and that's intentional. We design and implement the safeguarding, but the formal Pre-Start Health and Safety Review and final sign-off is always completed by an independent, arms-length safety engineer — someone with no stake in the system passing other than worker safety. We coordinate that review and prepare everything the reviewing engineer needs.
What's included in a risk assessment?
A task-by-task hazard identification, with severity, exposure, and avoidance scored to determine a risk category for each hazard. That assessment is what drives the safeguarding design and the safety circuit requirements that follow.
How do you size a light curtain or guard?
Using safe distance calculations — combining the machine or robot's worst-case stopping time, the response time of the safety device, and its depth penetration factor — rather than defaulting to a standard catalog size.
Can you audit an existing safety system?
Yes. We review installed guarding, interlocks, and safety circuits against current standards and identify gaps — useful before a PHSR, after a modification, or just to confirm an aging system still holds up.
Who actually reviews and signs the PHSR?
An independent safety engineer or specialist with no role in designing the system — arms-length from us, by design, to avoid any conflict of interest. We coordinate the review and supply the technical package; they own the sign-off.
Ready to Discuss Your Project?
We work with plant managers, OEMs, and integrators across Ontario. Let's talk about what you need.
+1 (905) 960-9535company@gohncontrols.comSend Us a Message