Date Posted

September 9, 2021

Dave Elniski
Industry Advisor, Safety & Compliance

This article was originally published by Western Canada Highway News in its Fall 2021 edition.

“A general problem with prescriptive work rules of all types is that they require rote compliance instead of intelligent self-management.” – Dr. Ron Knipling, Safety for the Long Haul [1]

The above quotation is from a trucking crash causation and prevention book, Safety for the Long Haul, published by the American Trucking Association. In this quote, Dr. Knipling is referring to some of the limitations hours of service regulations pose to drivers and motor carriers when one considers the broader body of research surrounding human fatigue [1].

Prescriptive and non-prescriptive rules are important concepts for trucking safety professionals, and in this article, I will give an overview of each and explain how they may be of use to policy and procedure creators.

Prescriptive Rules

Prescriptive rules are rules that are very detailed and specific. These rules will lay out a path to compliance. This path may not be easy to understand or follow initially, but the rules have all of the necessary details contained within them and there is little room for alternate interpretations.

Prescriptivity is a spectrum, and there are certainly some rules that are more prescriptive than others. An example of fairly prescriptive legislation is the sections in Alberta’s Occupational Health and Safety Code that describe the responsibilities of joint worksite health and safety committees and health and safety representatives [2]. This Part of the Code outlines some specific requirements employers need to meet to ensure compliance with the Code, and due to its length, I won’t quote it here.

Despite the quote I used to start this article, I do not consider prescriptive rules to always be bad things. Specific rules allow compliance to be measured easily, and if done well can help ensure greater standardisation when standardisation is desirable. For example, you wouldn’t want to use a shop that does not follow a detailed manufacturer’s set of procedures when rebuilding an expensive engine. Such a task requires specific steps and actions, and there should be no extra washers and bolts at the end of the rebuild.

Non-Prescriptive Rules

Non-prescriptive rules, on the other hand, are those that provide guidance but leave significant room for their execution to be tailored to the unique needs of an organisation or person. When reading non-prescriptive rules, a reader looking for direction may find them overly vague. Alternatively, a different reader looking for a high-level overview and wanting to create their own system for compliance will appreciate the intrinsic freedom.

An example of a non-prescriptive rule is the Federal Motor Carrier Safety Administration’s (FMCSA) regulation that requires motor carrier employees and drivers to be trained in their applicable safety regulations. The requirement is simply stated as such:

§390.3 General applicability. […]

(e) Knowledge of and compliance with the regulations. (1) Every employer shall be knowledgeable of and comply with all regulations contained in this subchapter that are applicable to that motor carrier’s operations.

(2) Every driver and employee involved in motor carrier operations shall be instructed regarding, and shall comply with, all applicable regulations contained in this subchapter.” [3]

This is the regulatory guidance provided to motor carriers for training their drivers and employees in safe operations. Yes, the regulations that have to be taught are quite detailed, but the above ruleset does not confine the motor carrier to a narrow scope for how they want to train their staff; details concerning training methods are left to the employer.

Non-prescriptive rules like this offer the entities they regulate tremendous freedom in their application. However, they also do not provide much in terms of a yardstick for determining if the approach chosen is “good enough”. An organisation with a proactive safety culture would likely appreciate this non-prescriptive rule since it gives them the ability to train the way they see fit; however, non-prescriptive rules may be so vague that they allow for marginal actions aimed only at demonstrating compliance without addressing the spirit of the rule.  Overly non-prescriptive rules can also lead to arguments and subjectivity during audits.

Prescriptive vs Non-Prescriptive Approaches

I do not consider either prescriptive or non-prescriptive rules to be better than the other. They are each applicable to different situations, and there are times as a safety professional where I appreciate both.

High-risk tasks benefit from prescriptive rules. When entering hazardous confined spaces, for example, a detailed safe work procedure with flowcharts, checklists, and emergency response procedures will ensure greater control over a hazardous situation.

The trick is to recognise when prescriptive rules are going to be beneficial to the outcome. People do not like being told what to do. Prescriptive health and safety policies can come across as unnecessarily authoritarian which can damage an organisation’s culture. When certain tasks require detailed rules – whether because the task is high-risk or out of the organisation’s control – employers should do their best to explain why the detailed approach is necessary and be responsive to worker concerns.

A non-prescriptive approach to achieving an outcome is an opportunity to empower different people in a company. If a direct report understands what you are trying to achieve and you trust them to get to the outcome by whatever means they see fit, the direction and rules you impose can be dramatically simplified without sacrificing compliance.

Summary – Custom Compliance

Organisations must comply with the legislation that applies to their operations.  Policy alone does not guarantee compliance: the end results need to be checked to ensure compliance is being met. However, leaders can take a customised approach to compliance that meets all of the requirements of the legislation while being as palatable as possible to their organisation.

Policies and procedures need to be prescriptive enough to be of use in the guidance of operations.  But, once the unique needs of your organisation have been weighed out along with the amount of collective knowledge held amongst staff, a shorter and simpler set of rules may offer a higher degree of flexibility in meeting outcomes.

Being only human, I can be forgiven if I exhibit a certain degree of defensiveness when being told what to do. But, if I understand the importance and the why, I will gladly and diligently abide by the checklist and view it as a defence against harm and not an attack against trust.


1 – Ronald R. Knipling, “5.6 Hours-of-Service & Fatigue”. In Safety for the Long Haul, American Trucking Associations, Inc., 2009, page 218.

2 – “Part 13 Joint Work Site Health and Safety Committees and Health and Safety Representatives”, Occupational Health and Safety Code, Province of Alberta, accessed July 2, 2021,

3 – “§390.3   General applicability”, Federal Motor Carrier Safety Regulations, Electronic Code of Federal Regulations, accessed July 2, 2021,