Billing code
J310C — Carbon Monoxide Diffusing Capacity By Single Breath Method
Lung diffusing capacity (DLCO)
Bill J310 for carbon monoxide diffusing capacity measured by the single-breath method.
Watch for: Outside a hospital only the professional component (suffix C) is billable; not payable for routine pre-operative screening before non-thoracic surgery.
| Provider | Specialist | Assistant | Anaesthetist | Non-anaesthetist |
|---|---|---|---|---|
| $0.00 | $0.00 | $24.85 | $21.55 | $21.55 |
- Code
- J310C
- Description
- Carbon Monoxide Diffusing Capacity By Single Breath Method
- FHO+ basket
- Not in the FHO+ base rate basket (Schedule 2 or 2B).
- Effective date
- Apr 1, 2026
- Termination date
- No end date
Explanation
Updated October 26, 2026
Carbon monoxide diffusing capacity (DLCO) by the single-breath method, with technical and professional components.
What it covers
J310 is carbon monoxide diffusing capacity by the single breath method (H5).
The professional component covers supervision, quality control, any monitoring and the interpretation; the technical component covers performing the test and sending a signed written report to the referring provider (H1).
Billing rules
- Technical component (H, suffix B) is paid only at a hospital or a hospital's approved off-site premises; outside hospital only the professional component (P, suffix C) is billable (H1, H3).
- Each test with its own code is specific and must be ordered individually (H3).
- The interpretation must be done personally by the physician who claims the professional component; supervision and monitoring may be delegated to another physician (H1).
- Not payable for routine pre-operative screening before non-thoracic surgery, unless needed for respiratory diagnosis, anaesthetic decisions or optimizing respiratory disease before surgery (H3).
Often billed with
- Lung volumes (J307 or J311) and J304 flow volume loop, each ordered individually (H3–H5).
Related codes: J307, J311, J304, J301, J306
Source: Schedule of Benefits (July 1, 2026), Pulmonary Function Studies, Pulmonary Function Studies, page H5. Preamble H1–H3.
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