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Billing code

J308C — Carbon Dioxide Ventilatory Response

CO2 breathing response test

Bill J308 for a carbon dioxide ventilatory response test, which measures how breathing responds to carbon dioxide.

Watch for: Outside a hospital only the professional component (suffix C) is billable; a technical claim needs the service location indicator.

Code

J308C

Description

Carbon Dioxide Ventilatory Response

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 dioxide ventilatory response test, with technical and professional components.

What it covers

J308 is the carbon dioxide ventilatory response test, which measures how breathing responds to carbon dioxide (H5).

It has a technical (H) and a professional (P) component, defined in the Pulmonary Function Studies preamble (H1–H2).

Billing rules

• Technical (H) and professional (P) components are claimed separately: suffix B for H, suffix C for P (H3).
• The H component is payable only in a hospital or a hospital's approved off-site premises, and not for in-patients or patients admitted within 24 hours for the same condition (H1, GP11).
• Outside a hospital, only the P component is billable (suffix C); ICHSC technical costs are in the Schedule of Facility Costs (H3).
• The interpretation (element D) must be done personally by the physician claiming the P component; supervision and associated procedures may be delegated to another physician (H1).
• Each coded test is a specific test that must be individually ordered (H3).
• Not payable for routine pre-operative screening for non-thoracic surgery unless needed for respiratory diagnosis, anaesthetic decisions or optimizing the patient's respiratory disease before surgery (H3).

Common rejections

• VHC: OHIP describes this as 'SLI required for technical fee': a technical-component (suffix B) claim needs the service location indicator, and the H fee is only payable in a hospital or approved off-site premises (H1, GP11).

Related codes: J313, J322, J340, J310, J320

Source: Schedule of Benefits (July 1, 2026), Pulmonary Function Studies, page H5; preamble H1–H3.

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