When Are Safety Measures Not Required Because They’re Not ‘Reasonably Practicable’?


OHS laws typically set out a hierarchy of controls to deal with physical dangers like fall hazards. The top of the hierarchy is to use engineering to eliminate the danger. Thus, for example, surrounding every perimeter with sturdy guardrails would be the first choice way to eliminate fall hazards. But these measures may be extremely burdensome or infeasible for a particular workplace. That’s where the concept of practicability comes in. In some cases, the law requires employers to implement safety measures only when it’s “practicable” or “reasonably practicable” to do so. To comply with such requirements, safety coordinators must be prepared to answer two key questions:

  • What makes a safety measure “impracticable”?
  • And if a safety measure isn’t “reasonably practicable,” what, if any, alternatives must your company implement instead?

This analysis will help you answer both questions.

Defining Our Terms

Some OHS laws use the term “reasonably practicable” when referring to employers’ general duty to protect workers. For example, Sec. 4 of Newfoundland’s OHS Act states, “An employer shall ensure, where it is reasonably practicable, the health, safety and welfare of his or her workers.” In this context, the phrase “reasonably practicable” is used in an almost due diligence sense. It essentially requires you to do what someone in the employer’s position could reasonably be expected to do to ensure workers’ health and safety. This use of the term “reasonably practicable” isn’t the focus of this article. This article is about the meaning of the terms “practicable,” “impracticable” and “reasonably practicable” when they appear in parts of the law requiring specific safety measures.

What the Law Says

The OHS laws often say that an employer is required to implement a specific safety measure only if it’s practicable or reasonably practicable to do so (or unless implementing it would be impracticable). Examples:

  • Where workers are working above an open-top bin, hopper, vat, pit or other open-top enclosure that isn’t covered, the enclosure’s inside wall must be fitted with a fixed ladder, except where the operations carried on in the enclosure make such a fitting impracticable [Federal OHS Regs., Sec. 2.6(3)];
  • Employers must ensure that externally exhausted air from a ventilation system is, if reasonably practicable, prevented from entering a work site [AB OHS Code 2006, Sec. 387(2)(a)];
  • Workers can’t enter or remain in any place where there’s a danger of engulfment or entrapment by loose materials unless measures are taken, where practicable, to control these risks [BC OHS Regs., Sec. 4.44(b)]; and
  • If practicable, a worker who’s receiving a load or engaged in sinking a shaft shall be positioned so that no load or part of a load carried by a crane or similar hoisting device passes over the worker [ON Construction Regs., Sec. 103(3)].


What should a company do when the law says that a safety measure is required if it’s practicable (or not required because it’s impracticable)? The Insider suggests that you take the following steps:

Step #1: Determine If Required Measure Is Practicable

The first thing you need to do is determine whether the required safety measure is actually “practicable,” “reasonably practicable” or “impracticable.” How? Start with the definition of the term in the law. Unfortunately, though, not every jurisdiction defines these terms:

3 definition jurisdictions. The OHS laws of only three provinces—BC, NS and SK—specifically define “practicable” and/or “reasonably practicable.” The BC definition of “practicable” (that “which is reasonably capable of being done”) isn’t particularly helpful. However, BC’s OHS Guidelines do provide guidance for applying that definition to certain required safety measures. For example, Section 7.6(b) includes “economic factors” as a factor in determining whether engineered noise controls are practicable. And in deciding if it’s practicable to eliminate, as opposed to merely control, ergonomic risk factors, Section 4.50(1) of the Guidelines lists “relevant considerations” as including:

  • Degree of risk to a worker arising from risk factors;
  • Extent of available information on the risk and means of controlling it;
  • Availability and suitability of countermeasures;
  • How often workers perform tasks that involve risk factors; and
  • Resources needed to control the risk.

NS and SK use the terms “practicable” and “reasonably practicable,” which aren’t synonymous. “Practicable” is defined as “possible, given current knowledge, technology and invention” (emphasis added).  “Reasonably practicable,” by contrast, is defined as “practicable unless the person on whom a duty is placed can show that there is a gross disproportion between the benefit of the duty and the cost, in time, trouble and money, of the measures to secure the duty.” So it’s much harder to avoid implementing a “practicable” measure than one that must be “reasonably practicable.”

11 no definition jurisdictions. The other 11 jurisdictions—Fed, AB, MB, NB, NL, NT, NU, ON, PE, QC and YT—use the terms “practicable” and/or “impracticable” in their OHS laws but don’t define the terms. However, you need to read the regulation in case it includes guidelines explaining what factors should be weighed in determining whether the particular required measure is practicable (the way BC does in its OHS Guidelines).

In addition, the federal government provides some guidance. Human Resources and Social Development Canada has released Criteria for Reasonably Practicable – General, a guidance document available at www.hrsdc.gc.ca/cgi-bin/hrsdc-rhdsc/print/print.asp?Page_Url=/en/lp/lo/opd-ipg/ipg/055.shtml, that explains what factors a Health and Safety Officer should consider when assessing whether certain safety measures are “reasonably practicable.” These factors mirror the “reasonably practicable” factors used in NS and SK, but are spelled out in more detail:

  • Technical aspect of complying—that is, is it possible to comply and will compliance introduce other hazards or areas of non-compliance, such as nullifying any required CSA, ULC or similar agency approval?
  • Impact of complying—that is, will the required measures advance workplace health and safety enough to make a noticeable improvement?
  • Economic aspect—that is, for the amount of improvement to workplace health and safety, would the cost be justified (i.e., large expenditure for a small reduction in the hazard level)?
  • Length of time during which the requirement will benefit the workplace—that is, how long will the measures taken be in service or in place?
  • Attempts made to comply with the requirement—that is, has an effort that has been undertaken resulted in the best improvement possible in workplace health and safety?
  • Degree of risk present—that is, how significant is the existing hazard? An improvement in a high-risk area may be more beneficial to the workplace than the same improvement in a low-risk area.

Unfortunately, we couldn’t find any guidance documents or cases from the other 10 jurisdictions that shed any light on the definition or interpretation of “practicable, reasonably practicable or impracticable.

Bottom line: If your company is located in BC, NS or SK, use the OHS law’s definition to guide you in determining if the safety measure is practicable or reasonably practicable. And if your workplace is federally regulated, use the factors from the guidance document. But what if your company is in one of the other 10 jurisdictions? Your safest course is to utilize the definitions from the other jurisdictions, including the federal factors, as guidelines. After all, if a court is ever asked to determine if you made the right call, it’s likely to look at those definitions and factors for guidance.

POINTER: If you determine that a safety measure isn’t practicable or reasonably practicable (depending on the standard for that measure), you should document how you arrived at that conclusion. Then if you’re ever asked by a government inspector why the safety measure wasn’t implemented or are charged with an OHS violation for failing to implement that measure, you’ll be prepared with adequate proof.

Step #2: Make the Appropriate Implementation Decision

If you determine that the safety measure is practicable or reasonably practicable, you must implement it. But what happens if you come to the opposite conclusion—that is, you conclude that the measure is impracticable? Again, the law doesn’t provide much in the way of specific guidance.

Only one jurisdiction has any sort of procedure for employers to follow in this situation. Sec. 157 of the Canada Labour Code states that the OHS regulations may require an employer to report to a safety officer the reason that full compliance with a standard isn’t practicable or reasonably practicable in particular circumstances. However, the federal OHS Regulations require such a report only for a few safety measures, such as those regarding hearing protection and fall-protection systems. Otherwise, there’s no procedure in place for dealing with impracticable safety measures.

Nova Scotia’s Reference Guide to the OHS Act notes that “reasonably practicable” is used as a test to determine when compliance will be required. The Guide explains that the burden is on the party that wants to avoid implementing the measure to prove that all of the costs of compliance (in terms of time, trouble and money) are not only prohibitive but also greatly outweigh the benefits to workers. But neither the OHS laws nor the Guide states when such proof is required or to whom it must be presented.

The OHS laws in the remaining jurisdictions don’t require you to report when you determine that a measure isn’t practicable or submit a body of evidence to support your conclusion. If you decide that the measure isn’t practicable, you don’t have to implement it. However, you’re not absolved of the duty to protect workers from the hazard the safety measure was meant to address. In other words, you can’t simply do nothing. Instead, you must implement an alternate measure that’s:

Specified by law. In some cases, the OHS law says exactly what alternate measures you must take. For example, Sec. 45.1(2) of Manitoba’s Workplace Safety and Health Act states that if it isn’t reasonably practicable to use safety-engineered needles in a medical workplace, the employer must ensure that safe work procedures and practices relating to the use of hollow-bore or intravenous needles are implemented. And under Sec. 50(1) of New Brunswick’s OHS Act, if an individual fall arrest system or other method of fall protection isn’t practicable, an employer must ensure that a safety net is installed to protect the worker. And if you fail to implement the specified alternate measure, your company is likely to face safety charges.

Example: While inspecting a job site, a safety officer saw an apprentice electrician installing a light fixture with the breaker and light switch turned off but not locked out. He asked the apprentice if the circuit breaker was locked out. The apprentice didn’t know what the officer meant. In fact, no one on the work crew was familiar with lockout procedures. The company was charged with two safety violations.

The BC Workers’ Compensation Appeal Tribunal ruled that the company didn’t exercise due diligence. The company owner said that the lockout procedures required by the regulations weren’t “practicable” because of the physical arrangement of the panel, which prevented an effective lock from being applied. But at the hearing, the safety officer demonstrated that at least one kind of lock could have been used. And even if lockout of the panel was impracticable, the regulations required written alternate safe work procedures that address certain topics, including the use of PPE and ladders, which the company didn’t have [WCAT-2007-03204].

Provides equal or better protection than the required measure. In other cases, the OHS law states that the alternate measure must provide equal or better protection than the impracticable measure without specifying exactly what those measures are. For example, Sec. 36(4) of NT’s and NU’s Safety Regulation says that if an employer can’t comply with certain confined space requirements, it “shall develop and implement alternate procedures that will provide equal or greater protection to workers.” However, even if your OHS law doesn’t contain this requirement, you must comply with it anyway. Remember: the company’s primary duty is to ensure the health and safety of its workers. And if it can’t fulfill that duty through the safety measure designated in the law, it needs to do so through another measure that’s equally as effective.


In most circumstances, your company will be able to implement the safety measures designated by the OHS laws. But it’s comforting to know that the OHS laws have some built in flexibility for those measures that aren’t feasible to use in every situation. The laws acknowledge that every workplace is different and that safety measures that are practicable for some workplaces may not be for others. As a safety coordinator, it’s your job to ensure that the company implements the safety measures that are practicable or reasonably practicable and acts with caution before deciding that a measure is impracticable and thus that implementation of that measure isn’t required.


WCAT-2007-03204, [2007] CanLII 66872 (BC W.C.A.T), Oct. 18, 2007


Here’s how your province or territory defines “practicable” and related terms:

FEDERAL: Uses the term “practicable” but doesn’t define it.

ALBERTA: Uses the term “practicable” but doesn’t define it.

BRITISH COLUMBIA: Defines “practicable” as meaning that which is reasonably capable of being done [OHS Regs., Sec. 1.1].

MANITOBA: Uses the term “practicable” but doesn’t define it

NEW BRUNSWICK: Uses the term “practicable” but doesn’t define it.

NEWFOUNDLAND/LABRADOR: Uses the term “practicable” but doesn’t define it.

NORTHWEST TERRITORIES/NUNAVUT: Uses the term “practicable” but doesn’t define it.

NOVA SCOTIA: Defines “practicable” as meaning possible, given current knowledge, technology and invention [OHS Act, Sec. 3(y)]. Defines “reasonably practicable” as meaning practicable unless the person on whom a duty is placed can show that there is a gross disproportion between the benefit of the duty and the cost, in time, trouble and money, of the measures to secure the duty [Sec. 3(ab)].

ONTARIO: Uses the term “practicable” but doesn’t define it.

PRINCE EDWARD ISLAND: Uses the term “practicable” but doesn’t define it.

QUéBEC: Uses terms “impractical,” “practicable” and “reasonable” but doesn’t define them.

SASKATCHEWAN: Defines “practicable” as meaning possible given current knowledge, technology and invention [OHS Act, Sec. 3(y)]. Defines “reasonably practicable” as meaning practicable unless the person on whom a duty is placed can show that there is a gross disproportion between the benefit of the duty and the cost, in time, trouble and money, of the measures to secure the duty [Sec. 3(aa)].

YUKON: Uses the term “practicable” but doesn’t define it.