Quick facts
- A hematocrit measurement is the packed cell volume of a blood sample, read from a capillary tube after centrifugation or from an automated analyser.
- In the United States the family is filed under 21 CFR 864.6400, Hematocrit measuring device, at Class II, product code GHY (Hematocrit, Tube, Rack, Sealer, Holder).
- In Canada the same tube, sealer and reader are non-invasive devices with no named entry, so Rule 7(1) of the Medical Devices Regulations places them at Class I.
- That is a genuine cross-border gap on the same bench item: Class II in the United States, Class I in Canada, decided by whether the rule names the device or describes it.
- Capillary blood collection tubes are a separate entry from the hematocrit measurement family, and the two should not be mixed on a purchase order.
- Entries, classes and product codes were checked against the current eCFR text, the Regulations and the openFDA classification database on 2026-10-12.
A hematocrit reading is one of the oldest numbers a laboratory reports, and the hardware behind it - a capillary tube, a sealing compound, a rack, a reader or a microcentrifuge - is bought as a family. In the United States that family is a named Class II entry; in Canada the same items fall under the catch-all rule for non-invasive devices at Class I. This article sets out both routes and why a supplier and a laboratory can describe the same box of tubes two different ways. The graduated specimen cups used at the receiving bench come from the same laboratory consumables range.
What counts as a hematocrit measuring device?
The measurement itself is simple: a blood sample is spun so that the red cells pack and the column of packed cells is read against the total column height. The hardware that makes the reading possible is a small family. A capillary tube holds the sample; a sealing compound or clay plug closes one end; a rack holds the tubes for the spin; a microcentrifuge provides the force; and a reader or a card scale turns the column into a number.
An automated analyser that reports a hematocrit from a whole-blood sample is a different device, but it sits in the same regulatory family because its intended use is the same measurement. The point that matters for class is not how the number is produced but what the device is for: measuring the packed cell volume of blood.
Is a hematocrit device Class II in the United States?
Yes. 21 CFR 864.6400 is titled Hematocrit measuring device and the entry sits at Class II. The openFDA device classification API lists the practical items under product code GHY, Hematocrit, Tube, Rack, Sealer, Holder, with GKG, Centrifuge, Hematocrit, and JPI, Device, Hematocrit Measuring, in the same regulation number.
Class II means the device reaches the market with special controls in addition to general controls: a performance standard or a guidance document, and usually a premarket notification. The reason a tube and a sealer are pulled up to that level rather than staying at Class I is that the reading the family produces is used in clinical decisions, and a wrong number is not cosmetic.
How does Canada class the same hematocrit items?
Canada keeps no named entry for a hematocrit tube or a reader. It applies the rules in Schedule 1 of the Medical Devices Regulations. A tube, a sealer and a rack are non-invasive; they do not contact injured skin, they do not channel or store fluids for introduction into the body, and they do not modify blood for introduction back into the body. They fall to Rule 7(1), which classes "all other non-invasive devices" as Class I.
The rule that could lift them is Rule 7(2): a device is Class II if it is intended "to act as a calibrator, tester or quality control support to another medical device", or "to be connected to an active device that is classified as Class II, III or IV". A plain tube and a clay sealer do neither, so they stay at Class I. An automated reader that is designed to calibrate or control a Class II analyser can move, and that is the line to check before assuming every item in the family is Class I north of the border.
| Item | Canada | United States |
|---|---|---|
| Named entry | None; classified by rule | 864.6400, Class II |
| Product codes | Not applicable | GHY; GKG; JPI |
| Class | Class I (Rule 7(1)) | Class II (special controls) |
| Governing text | Schedule 1, Rule 7(1) | 21 CFR 864.6400 |
| Lift to Class II? | Rule 7(2): calibrator or connected to a Class II+ active device | Not applicable |
| Route to market | Establishment licence; no device licence for Class I | Premarket notification with special controls |
Why is the Canadian answer different from the US answer?
The two systems classify in different directions. The United States names the device and attaches a class to the name; whether the item is a tube, a rack or a reader, the name is hematocrit measuring device and the class travels with it. Canada defines risk rules and lets the device fall into one of them, and a passive tube simply does not trip any of the rules that raise a class.
That difference changes how a buyer should read a specification sheet. A US supplier will point at the regulation number and the product code. A Canadian buyer has to ask a rule question first: does this item touch the patient, does it carry a fluid for introduction into the body, or is it a calibrator for an active device? For a tube and a sealer the answer is no three times, and the class is Class I.
Which standards keep a hematocrit measurement traceable?
The measurement side of the bench is governed by laboratory standards rather than by the device rules. ISO 15189:2022 sets the requirements for quality and competence in a medical laboratory and is the framework a laboratory is accredited against; the Clinical and Laboratory Standards Institute publishes the method documents that describe how a packed cell volume is determined and how the result is reported. Public Health Ontario carries the provincial laboratory material that many Ontario laboratories work to.
The device side is governed by the usual quality and risk standards. A manufacturer works under ISO 13485:2016 and keeps a risk file under ISO 14971:2019. Where a tube is supplied sterile inside packaging, that packaging follows ISO 11607-1:2019.
Which tube belongs on which order?
Two families of capillary tube are sold into the same laboratory and they are not interchangeable on a purchase order. A capillary blood collection tube is the sampling device - it is held to the puncture site and fills by capillary action, and its class follows the blood collection rules. A hematocrit tube is the measurement device - it takes an already-collected sample, is sealed, and is spun. The sizes, the coatings and the intended use differ, and the class can differ too.
| Item | Purpose | Regulation number, US | Class, US |
|---|---|---|---|
| Capillary blood collection tube | Collect the sample | 864.6150 | I |
| Hematocrit tube | Hold the sample for the spin | 864.6400 | II |
| Sealer or clay plug | Close the tube before centrifugation | 864.6400 | II |
| Hematocrit rack or holder | Hold tubes in the centrifuge | 864.6400 | II |
| Hematocrit centrifuge | Provide the separating force | 864.6400 | II |
The distinction is worth writing into the order description. A laboratory that orders a hematocrit tube when it meant a blood collection tube gets the wrong class, the wrong coating and, often, the wrong result.
How should a laboratory stock the hematocrit bench?
Stock by method. A laboratory that reads hematocrit from a spun capillary tube keeps tubes, sealer, a rack that matches its centrifuge rotor, and a reading card or reader. A laboratory that reports from an analyser keeps the analyser's consumables and its quality control material. Standardise the tube and the sealer so that one rotor holds them all, and record the lot numbers against the run.
Record by lot and by run. A result is only traceable if the tube lot, the sealer, the centrifuge setting and the operator can be recovered later, and the sample-handling side of the bench - graduated specimen cups for the receiving area and nitrile examination gloves for the bench - belongs on the same restock list. The laboratory consumables range is listed under diagnostic laboratories, and multi-site groups order at case level through the wholesale and multi-site ordering page. Reselling? become a distributor.
Sources
- openFDA device classification API
- Medical Devices Regulations, SOR/98-282, full text and Schedule 1
- US FDA, medical devices
- US FDA, medical device databases
- US FDA, overview of device regulation
- Health Canada, medical devices
- Health Canada, establishment licensing
- Standards Council of Canada
- CSA Group
- ISO 13485:2016, medical devices quality management
- ISO 14971:2019, risk management of medical devices
- CCOHS, OSH answers
- Clinical and Laboratory Standards Institute
- Public Health Ontario, laboratory services
- ISO 15189:2022, medical laboratories, requirements for quality and competence
- World Health Organization, laboratory biosafety guidance
- US CDC, laboratory quality
- ISO 13485:2016, medical devices quality management
- ISO 14971:2019, risk management of medical devices
- 21 CFR 864.6400, hematocrit measuring device
- 21 CFR 864.6150, tube, collection, capillary blood
A hematocrit bench lives on lot numbers and run records. The printable blank run log at the compliance log centre gives a column for the tube lot, the centrifuge setting and the operator, and it prints without an account and no sign-up.
A laboratory running several benches can use the log generator on the same page to lay out one sheet per bench before printing the set.
Have a question about your own facility? Send it in and you will get a written answer specific to your equipment and province, with the regulation or standard it is based on cited. Ask a compliance specialist about the device you are buying.
Related reading
- Capillary tubes in Canada vs the US: which size and standard
- Blood collection tube systems in Canada vs the US: which order
- Microtomes in Canada vs the US: which class applies
CliniEco Medical supplies eye care, laboratory and dental consumables of the kind described in this article. MDEL #35334. This article is written for optometry, laboratory and dental procurement professionals and is not legal advice; the class of a device and the records kept by a practice belong to the manufacturer and to the requirements that apply to it.
Frequently Asked Questions
Is a hematocrit tube a Class II device?
In the United States, yes. 21 CFR 864.6400 is titled Hematocrit measuring device and covers the tube, rack, sealer, holder, centrifuge and reader as Class II. In Canada the same items are non-invasive devices and fall to Class I under Rule 7(1) of the Medical Devices Regulations.
Why does Canada class a hematocrit tube at Class I when the US classes it at Class II?
Because the two systems classify differently. The United States attaches a class to a named device entry that includes the whole family, while Canada applies risk rules and lets each device fall into one. A passive tube does not trip any Canadian rule that raises a class, so it stays at Class I.
When would a hematocrit item be lifted to Class II in Canada?
Under Rule 7(2), a non-invasive device is Class II if it is intended to act as a calibrator, tester or quality control support to another medical device, or to be connected to an active device that is Class II, III or IV.
Is a capillary blood collection tube the same entry as a hematocrit tube?
No. Capillary blood collection tubes sit at 21 CFR 864.6150 and are sampling devices. Hematocrit tubes, sealers and readers sit at 864.6400 and are measurement devices. The two should not be substituted on a purchase order.
What are the product codes for hematocrit devices in the United States?
The openFDA classification database lists GHY for Hematocrit, Tube, Rack, Sealer, Holder, GKG for Centrifuge, Hematocrit, and JPI for Device, Hematocrit Measuring, all under 864.6400 at Class II.
Which standard covers the laboratory that runs the test?
ISO 15189:2022 sets the requirements for quality and competence in a medical laboratory. The Clinical and Laboratory Standards Institute publishes the method documents for how a packed cell volume is determined.
Where should a laboratory record a hematocrit run?
In the run log the laboratory keeps for the bench, showing the tube lot, the centrifuge setting and the operator. The compliance log centre provides a printable blank form and a log generator sized to the number of benches a laboratory runs.
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