Decoding the Language of Standards: Should vs. Shall

The recent promotion of NFPA 70B from a guide to a standard carries significant implications for electrical maintenance. We recently published a blog that reviews this status change in detail.

This upgrade is an opportune time to address a question we often receive: In the context of industry standards, what’s the difference between “should” and “shall”? When it comes to arc-rated and flame resistant (AR / FR) apparel, it’s important to distinguish between those two words. In the video below, Scott Margolin, Vice President of Technical at Tyndale, provides more context:


What’s the Difference Between “Should” and “Shall?”

In simplest terms, “should” is something you ought to do. “Shall” is something you must do.

What’s the Difference Between a Guide and a Standard?

When a publication is classified as a guide: it’s a recommended practice indicating what you should do. Guides strictly use “should” in their language.

When a publication is classified as a standard: it’s a requirement indicating what you shall do. Standards strictly use “shall” as prescriptive language. Any actions following the word “shall” are not optional.

To examine the differences, let’s compare the 2019 edition of NFPA 70B1  with the 2023 edition of NFPA 70B2.

NFPA 70B – 2019 Edition

This edition is titled Recommended Practice for Electrical Equipment Maintenance. It defines “Recommended Practice” in Section 3.2.4 as “A document that is similar in content and structure to a code or standard, but that contains only nonmandatory provisions using the word ‘should’ to indicate recommendations in the body of the text.”

“Should” is also defined in section 3.2.5: “Indicates a recommendation or that which is advised but not required.”

Since this edition was written as a recommended practice and not a standard, the publication uses the word “should” instead of “shall,” as in the example below:

  • – All employees who face a risk of electrical hazard should be trained to understand the specific hazards and related injuries associated with electrical energy.

NFPA 70B – 2023 Edition

This edition is titled Standard for Electrical Equipment Maintenance and includes the definition of the word “Standard” in Section 3.2.6: “An NFPA standard, the main text of which contains only mandatory provisions using the word ‘shall’ to indicate requirements and that is in a form generally suitable for adoption into law.”

“Shall” is defined in Section 3.2.5: “Indicates a mandatory requirement.” An example of “shall” language in the 2023 edition is shown below:

  • 3.3 – A qualified person responsible for conducting electrical maintenance shall be trained in the specific maintenance tasks, test methods, test equipment, PE usage (as applicable), and hazards associated with the electrical equipment or system being serviced.


At Tyndale, we know that guides and standards are essential to safeguard employees. That’s why we ensure that the AR / FR clothing we sell complies with all applicable industry safety standards, so workers can do their job and return home safely.

Click here for more information on AR / FR clothing standards.


References for this post were accessed in May 2023:

(1) NFPA 70B: Recommended Practice for Electrical Equipment Maintenance, 2019 Edition. Retrieved from

(2) NFPA 70B: Standard for Electrical Equipment Maintenance, 2023 Edition. Retrieved from

Leave a Reply

Your email address will not be published. Required fields are marked *