---
title: Revisiting 'Should, Shall and Must'
description: How to interpret SHOULD, SHALL, and MUST in FDA, OSHA, and USP <800> regulations.
image: https://www.rpharmy.com/hubfs/Should%2c%20Shall%2c%20Must.png
---
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## Safety First Blog
# Revisiting 'Should, Shall and Must'
Posted by [Laura Paxton](https://www.rpharmy.com/blog/author/laura-paxton) on Jul 7, 2022 10:09:48 AM
Find me on:
[LinkedIn](https://www.linkedin.com/in/laura-paxton-4ab3ab4/)
**Spelling Out These Legal Terms in Hazardous Drugs Regulations**
We're revisiting this blog first published in January 2021 because the terms 'should, shall, must' continue to cause confusion when trying to comply with FDA, OSHA, and USP <800> regulations. Are you one of many healthcare workers still searching for clear definitions of these tricky terms? We're here to help!
Each of these terms have specific meanings when used in legal documents, meanings that are a bit different than when we use the terms in everyday language. Here’s a rundown of where these legal terms appear and what they mean exactly.
**Where might you see the terms *should*, *shall,* and *must*?
**The FDA uses these terms in regulations based on the Federal Food, Drug, and Cosmetic Act (FD&C Act). Regulations such as USP <800> provide legal authority to the FDA.
Medical facilities often rely on another set of documents called “FDA guidance documents” to further explain regulations. Guidance documents do not set new legal standards or impose new requirements like regulations. Because of this, they cannot include mandatory language such as *shall*, *must*, *required*, or *requirement*, according to the[ Code of Federal Regulations](https://www.ecfr.gov/cgi-bin/text-idx?SID=a31c6a9ffb643806558b9b6ea3910c4c&mc=true&node=se21.1.10_1115&rgn=div8) (CFR).
**What do *should*, *shall,* and *must* mean within USP <800> and other FDA regulations?*****Should*** means it is “better than not,” and is suggestive vs. mandatory. *Should* reads as a recommendation allowing the reader to make their own judgment.
Example from USP <800> on Administering an Oral Liquid Dose :
“Appropriate techniques and ancillary devices ***should*** be used when the dosage form allows and ***should*** be based on your healthcare facility’s protocols, procedures or SOPs.”
In everyday English, ***shall*** is a synonym to *will*, *may,* or *is*. In contrast, its legal definition is definitive; it means *must *or *mandatory*. In fact, FDA regulations frequently use *shall* to state mandatory requirements.
Example:
“A regulation published in accordance with §171.100(a) ***shall*** become effective upon publication in the Federal Register.” [CFR §171.102](https://www.ecfr.gov/cgi-bin/text-idx?SID=56e9fd1397bda96ea010d3ac1b030fab&mc=true&node=se21.3.171_1102&rgn=div8) (Re-read it and replace *shall* with *must* for the intended legal meaning.)
*Shall* is one of the most litigated words in the English language, according to Bryan Garner, editor of *Black's Law Dictionary. *Garner and others object to its use because it is rarely used in conversation, and its meaning is ambiguous. In fact, Garner has proposed omitting *shall* from legal documents all together*. *As that is not the case, when you see the word *shall*, you can replace it with *must* to understand the intent.
***Must*** is a “word of obligation” and imposes a legal obligation about a mandatory rule. Its definition in our everyday use and legal use are the same making it much easier to decipher.
Example from USP <800> on Administering an Oral Liquid Dose :
“Appropriate PPE ***must*** be worn based on your healthcare facility’s protocols, procedures or SOPs.”
**Summary
**In summary, as you prepare for USP <800> inspections, audits by the Joint Commission, or ensure safety procedures are up-to-date, ***shall*** and ***must*** are the two terms to look out for as they require action or compliance. ***Should*** leaves room open for you to decide whether your facility follows the recommendation.
And that concludes our grammar lesson for the day. :-) We hope this information helps you better understand the legal definitions of ***should, shall*** and ***must***. If you have other questions about the FD&C Act, regulations, or guidance documents, please submit them here and we’ll work to answer them in future blogs.
Check out our blog on [Data Overload](https://www.rpharmy.com/blog/data-overload) where we share insight into what healthcare facilities are faced with as they work to comply with USP <800>.
Topics: [Rhazdrugs](https://www.rpharmy.com/blog/tag/rhazdrugs), [Policy](https://www.rpharmy.com/blog/tag/policy), [USP <800>](https://www.rpharmy.com/blog/tag/usp-800), [Formweb](https://www.rpharmy.com/blog/tag/formweb)
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