Ontario construction sites are governed by a web of regulations that each impose specific signage and posting obligations. O. Reg. 213/91 covers the project sign, Notice of Project, emergency contacts, and most hazard-specific warnings. OHSA itself requires the green poster and JHSC/H&S rep postings. O. Reg. 860 handles WHMIS labels. O. Reg. 632/05 covers confined spaces. O. Reg. 278/05 covers asbestos. A Ministry of Labour inspector walking your site will check for every one of these. Missing a single required sign can trigger a compliance order, and if a worker is injured in an area that should have been signed, the absence of that sign becomes evidence of non-compliance in the prosecution.
Before any construction work begins, O. Reg. 213/91 section 11(1) requires the constructor to post a project sign that is visible from a public way adjacent to the project. The sign must show the project address, the constructor's name, and the constructor's WSIB registration number. This is not a nicety — it is the first thing an inspector looks for when approaching a site. The purpose is twofold: it tells the public and the Ministry who is responsible for the project, and it confirms that the constructor has active WSIB coverage. A site without a project sign is a site that is either unregistered with WSIB or does not know who is in charge, and both of those situations are enforcement priorities. The sign does not need to be large or expensive — a painted sheet of plywood or a printed sign on the construction fence is fine — but it must be legible from the public way and it must contain all three required elements. Inspectors have issued compliance orders for signs that show the constructor name but omit the WSIB number, or signs that have faded to the point of illegibility.
Not every construction project triggers the Notice of Project requirement, but most significant ones do. O. Reg. 213/91 section 6(1) requires the constructor to file a Notice of Project with the Ministry of Labour before construction begins if the project is expected to last three or more months, or if the total cost of labour and materials is expected to be $50,000 or more. The notice must include the project location, the constructor's name and address, the expected start and end dates, a description of the work, and the constructor's WSIB registration number. A copy must be kept on the project site. Filing can be done online through the Ministry's e-Filing system. The penalty for failing to file is a compliance order at minimum, and the absence of a filed Notice of Project becomes a factor in any subsequent enforcement action. If you are unsure whether your project crosses the threshold, file anyway — there is no penalty for filing a Notice of Project for a project that turns out to cost less than $50,000 or last less than three months.
Every employer in Ontario must post the current OHSA poster — formally titled "Health & Safety at Work — Prevention Starts Here" — in a conspicuous location in the workplace. On a construction site, this means the site trailer, the lunchroom, or the main entry point where workers sign in. The poster covers the three fundamental worker rights under OHSA: the right to know about hazards, the right to participate in health and safety through the JHSC or H&S representative, and the right to refuse unsafe work. It also summarizes employer duties, supervisor duties, and worker duties. The word "conspicuous" is doing important legal work here — the poster cannot be in a closed filing cabinet, behind a door that is usually shut, or in a trailer that workers do not regularly enter. It must be where workers can see it during their normal routine. The poster is available free from the Ministry of Labour website and ServiceOntario offices. There is no excuse for not having one, and inspectors cite it frequently as a baseline indicator of whether the employer takes compliance seriously.
O. Reg. 213/91 section 17 requires that emergency contact information be posted at the project and accessible to all workers. At minimum, this includes the telephone number for emergency services (911), the name, address, and telephone number of the nearest hospital or health care facility, the name and telephone number of the employer's designated emergency contact, and the name and telephone number of the site supervisor. On projects in remote areas where 911 service may not be reliable, the contact information for the nearest ambulance service and fire department should also be posted. The emergency contact list should be posted near a telephone or where workers gather — not buried in the site office. If a worker is injured and cannot quickly find the emergency contact information, the posting requirement has failed its purpose. Review and update the contacts regularly, especially on long-duration projects where supervisors and site office numbers may change.
WHMIS 2015, implemented through O. Reg. 860, requires that every container of a hazardous product in the workplace bear a GHS-compliant label. This label must include the product identifier, the supplier identifier, GHS pictograms (the red diamond-shaped hazard symbols), the signal word (Danger or Warning), hazard statements, precautionary statements, and a reference to the Safety Data Sheet. When a hazardous product is transferred from its original container to another container for use — a common practice on construction sites with paints, solvents, adhesives, and cleaning products — the new container must have a workplace label that includes the product identifier, safe handling instructions, and a reference to the SDS. The most common violation inspectors find is unlabelled containers: a painter pours solvent into a coffee can, a labourer mixes a cleaning solution into a spray bottle, or a contractor stores diesel in an unmarked jerry can. Each of these is a WHMIS violation and each can draw a compliance order. The SDS binder must be physically accessible to workers at the workplace — not locked in the supervisor's truck or stored only on a computer that workers cannot access. Workers must receive WHMIS training before they handle any hazardous product, and that training must be specific to the hazardous products they will encounter on the site.
Asbestos warning signs under O. Reg. 278/05 are required at every approach to an area where asbestos-containing material may be disturbed. The sign must read "DANGER — ASBESTOS" or equivalent and must be posted before any asbestos work begins. For Type 2 and Type 3 asbestos operations, the work area must be enclosed with polyethylene sheeting under negative pressure, and the warning signs must be at every approach to the enclosure. The regulation is strict because even brief exposure to airborne asbestos fibres can cause mesothelioma, a fatal cancer with no cure. Workers who unknowingly walk into an unsigned asbestos abatement area are exposed to a risk they had no opportunity to assess or refuse. Confined space warning signs under O. Reg. 632/05 serve a similar life-safety function. Every entrance to a confined space — manholes, vaults, tanks, silos, pits — must be marked with a sign warning that the space is a confined space and that entry without authorization is prohibited. Confined space fatalities typically involve multiple victims: one worker enters, collapses from oxygen deficiency or toxic atmosphere, a second worker enters to rescue them and also collapses, and sometimes a third. The warning sign is the first line of defence against this cascade. It must be clearly visible before a worker reaches the entrance, not discovered after they have already entered.
When a Ministry of Labour inspector arrives at a construction site, the signage check typically follows a predictable pattern. From the street, the inspector looks for the project sign with the constructor name and WSIB number. At the site entrance, they look for barricade and warning signs if the public has access nearby. In the site trailer or lunchroom, they check for the OHSA poster, the JHSC member names or H&S rep name, emergency contact numbers, the most recent MOL inspection report, and the SDS binder. Walking the site, they check for fire extinguisher location signs, first aid station signs, and any hazard-specific signs required by the conditions — confined space signs at manholes, asbestos signs at abatement enclosures, electrical hazard signs near overhead lines, crane warning signs and barricades at hoisting areas, and blasting signs if explosives are in use. They also check whether WHMIS labels are intact on all hazardous product containers. This entire walkthrough can happen in fifteen minutes, and each missing sign is a separate citation. The most common deficiencies that draw orders are: missing or illegible project sign, OHSA poster not posted, JHSC member names not posted, unlabelled hazardous product containers, and missing confined space signs. The fix for every one of these is cheap and fast — the cost of a compliance order and the schedule disruption of a stop-work order is not.