# What Do Specimen Numbers 1–10 Mean for CHEM-Class Laboratory Test Codes?

**URL:** <https://forum.loinc.org/t/what-do-specimen-numbers-1-10-mean-for-chem-class-laboratory-test-codes/3184>\
**Category:** General\
**Created:** [October 12, 2026, 5:40pm UTC](https://forum.loinc.org/t/what-do-specimen-numbers-1-10-mean-for-chem-class-laboratory-test-codes/3184 "2026-10-12T17:40:12Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![ivona1](https://forum.loinc.org/letter_avatar_proxy/v4/letter/i/35a633/32.png) [@ivona1](https://forum.loinc.org/u/ivona1)\
**Post date:** [October 12, 2026, 5:40pm UTC](https://forum.loinc.org/t/what-do-specimen-numbers-1-10-mean-for-chem-class-laboratory-test-codes/3184/1 "2026-10-12T17:40:12Z")

</div>

**Dear LOINC Community Forum,**

I came across the following laboratory test description:

“Glucose [Mass/volume] in Serum or Plasma --10th specimen”

It belongs to the **CHEM** class, and there are separate codes for specimens 1–9 as well.

If I am not mistaken, codes belonging to the **CHAL** or **CHAL.ROUTINE** properties and containing different specimen numbers are collected at certain intervals following the administration of a challenge (e.g., “Glucose [Mass/volume] in Serum or Plasma --5th specimen post lactose”)

However, I am now wondering what the specimen numbers signify for codes belonging to the **CHEM** class, where by definition, no challenge is administered.

Do they refer to blood collected in different tubes, a blood sample divided into multiple specimens, or a specific laboratory coding convention? Or does it indicate something else entirely?

I would greatly appreciate any clarification or insight into the meaning of these codes.

Thank you very much!

Ivona

---

<div class="post-metadata">

**Author:** ![pdbanning](https://forum.loinc.org/letter_avatar_proxy/v4/letter/p/9f8e36/32.png) [@pdbanning](https://forum.loinc.org/u/pdbanning)\
**Post date:** [October 13, 2026, 1:44pm UTC](https://forum.loinc.org/t/what-do-specimen-numbers-1-10-mean-for-chem-class-laboratory-test-codes/3184/2 "2026-10-13T13:44:44Z")

</div>

Hello Ivona and thank you for the question. You are correct in thinking about the clinically administered tolerance tests to a patient; they usually map to a specific dose of a challenge or will be noted with .

There are clinical trial labs however that may be administering to a cohort of participants with a protocol to follow. These would each be collected in separate tubes; they are not aliquots of one collection. There are several biomarkers in the LOINC database that allow for unspecified series of collections to be included [insulin, gastrin, prolactin, corticotropin, etc]

Hope this answers your question,

Pam

---

<div class="post-metadata">

**Author:** ![pitk0006](https://forum.loinc.org/letter_avatar_proxy/v4/letter/p/c89c15/32.png) [@pitk0006](https://forum.loinc.org/u/pitk0006)\
**Post date:** [October 28, 2026, 5:17pm UTC](https://forum.loinc.org/t/what-do-specimen-numbers-1-10-mean-for-chem-class-laboratory-test-codes/3184/3 "2026-10-28T17:17:39Z")

</div>

> [@ivona1](#):
>
> Do they refer to blood collected in different tubes, a blood sample divided into multiple specimens, or a specific laboratory coding convention? Or does it indicate something else entirely?

In addition to Pam’s response, the numbers usually refer to separate specimens that are collected and not the blood sample divided into multiple specimens. LabCorp lists the following multiple specimen tests: [Multiple-specimen Testing Guidelines | Labcorp](https://www.labcorp.com/test-menu/resources/multiple-specimen-testing)

Cordially,