Canadian Association of Diving Contractors

New edition strengthens clarity around occupational diving scope, SCUBA limitations, underwater construction sites, and minimum crew requirements

Mississauga, Ontario — May 15, 2026— The Canadian Association of Diving Contractors is drawing attention to several important changes in the upcoming CSA Z275.2-26 Occupational Safety Code for Diving Operations, the national standard that provides safety requirements for occupational diving operations in Canada.

The 2026 edition includes significant clarifications affecting how occupational diving operations are planned, classified, supervised, crewed, and carried out. The changes address the scope of the Standard, controlled environments, underwater construction sites, restrictions on the use of SCUBA, minimum SCUBA crew levels, and surface-supplied diving crew requirements.

“These changes are important because they help clarify the safety floor for occupational diving in Canada,” said Doug Elsey, P.Eng., Executive Director of the Canadian Association of Diving Contractors. “They reinforce that occupational diving requires proper planning, competent crews, appropriate equipment, effective supervision, and a clear emergency response capability.”

Occupational Diving Applies Across Industry Sectors

One of the most important changes in CSA Z275.2-26 is the clarification of the Standard’s scope.

The revised scope states that the Standard applies to all occupational diving operations conducted in connection with all types of work and employment, regardless of the industry sector in which the diving activity occurs.

CADC says this is a significant clarification for the general industry because occupational diving hazards are determined by the task, the site conditions, the diving method, the equipment, the emergency response plan, and the competence of the dive crew — not simply by the sector in which the work is being performed.

Whether the diving operation involves construction, salvage, aquaculture, film production, archaeology, inspection, scientific work, public safety, infrastructure, marine maintenance, or another occupational activity, the work must be assessed and managed as occupational diving.

“The sector label does not change the hazard,” Elsey said. “A diver underwater still requires proper supervision, standby capability, emergency planning, competent personnel, and equipment appropriate to the task.”

Controlled Environment Does Not Mean Reduced Safety

CSA Z275.2-26 introduces a definition of controlled environment, referring to a diving location where the risk to the diver is assessed as low and supported by a documented risk management assessment. Examples may include protected waterways, pools or tanks with unhindered access to the surface, tended or tethered SCUBA, and locations where there is minimal risk of a diver becoming trapped or lost.

However, CADC notes that the accompanying language is just as important: designating a dive location as a controlled environment does not alter or reduce the operational safety requirements specified elsewhere in the Standard.

This means that “controlled environment” should not be interpreted as permission to reduce safety without proper justification. The designation must be supported by documented risk assessment and actual site conditions. It does not remove the need for competent supervision, proper crew planning, standby diver readiness, emergency response capability, or compliance with other applicable requirements.

Underwater Construction Site Now Clearly Defined

The 2026 edition also adds a detailed definition of underwater construction site.

The definition includes underwater locations where construction, destruction, demolition, maintenance, repair, renovation, excavation, blasting, concreting, salvage, installation, disassembly of infrastructure, machinery or equipment, or similar activities are actively taking place. The definition also extends through the water column and onshore to include dive control.

CADC says this clarification is particularly important for clients, contractors, constructors, engineers, municipalities, utilities, insurers, regulators, and procurement authorities involved in underwater work.

The definition is relevant to active work areas involving infrastructure, pipelines, tunnels, intakes, ducts, bridges, roads, wharves, dams, anchorages, underwater film production sets, oil and gas platforms, vessels, and other underwater infrastructure sites.

“This helps remove ambiguity,” said Elsey. “If the work involves active underwater construction, maintenance, repair, demolition, installation, salvage, or similar activity, it must be treated as serious occupational diving work. That affects planning, equipment selection, crew size, supervision, and emergency response.”

SCUBA Restrictions Clarified and Strengthened

CSA Z275.2-26 also strengthens and clarifies where SCUBA shall not be used in occupational diving operations.

The Standard identifies several operations where SCUBA is prohibited, including underwater intakes and/or pipe entry, penetration diving, welding, burning/cutting, high-pressure jetting, most hoisting operations, dredging subject to limited exceptions, most use of power tools, planned diving beyond no-decompression limits, contaminated environments subject to limited exceptions, certain explosive-related work, and diving on an underwater construction site.

CADC emphasizes that SCUBA remains an accepted occupational diving technique where it is appropriate and permitted. However, the 2026 wording makes the limits clearer.

SCUBA has limitations in breathing gas supply, surface control, communications, diver recovery, and emergency response capability. For higher-risk occupational tasks, surface-supplied diving is often the more appropriate method.

“For clients and procurement authorities, this is an important point,” Elsey said. “A lower-priced bid based on SCUBA may not be an acceptable bid if SCUBA is not appropriate or permitted for the work being performed. The diving method has to match the hazard.”

Four-Person SCUBA Crew Confirmed as the Default Minimum

The 2026 edition clarifies that the default minimum SCUBA crew is four persons:

• two divers, one of whom acts as the standby diver;
• one diver’s tender; and
• one diving supervisor.

A reduced three-person SCUBA crew may only be considered under restricted conditions. These include diving in a controlled environment, a maximum depth not exceeding 18 m / 60 ft, no contaminated environment, a demonstrated and documented site-specific extraction of an unconscious diver, and a completed site-specific documented risk assessment process, including an emergency action plan.

CADC says this is an important clarification for both contractors and clients.

In practical terms, four is the default and three is the exception. A reduced crew must be justified by the actual conditions of the dive site and supported by proper documentation.

“This is about emergency response capability,” said Elsey. “The question is not simply how many people are needed to get the job done. The question is how many competent people are needed to get the diver out of trouble when something goes wrong.”

Surface-Supplied Diving Crew Requirements Remain Clear

For surface-supplied diving, CSA Z275.2-26 confirms that each operation requires a minimum four-person dive crew:

• two divers, one of whom acts as the standby diver;
• one diver’s tender; and
• one diving supervisor.

The Standard also confirms important standby diver requirements. The standby diver must use surface-supplied diving equipment, must be capable of responding to the depth of the working diver or divers, and must have adequate breathing gas arrangements to support emergency response.

CADC says the standby diver requirement remains one of the most important life-safety elements in occupational diving.

“The standby diver is not a name on a form,” Elsey said. “The standby diver is part of the emergency response system. In a diving emergency, that capability may be the difference between rescue and recovery.”

What This Means for the Industry

CADC says the changes in CSA Z275.2-26 should be reviewed carefully by all parties involved in occupational diving.

For diving contractors, the changes reinforce the need for clear procedures, site-specific risk assessments, proper crew planning, documented emergency response capability, and appropriate selection of diving methods.

For clients, owners, municipalities, engineers, constructors, and procurement authorities, the changes highlight the importance of evaluating diving bids based on safety, competency, equipment, supervision, and compliance — not simply price.

For regulators and safety professionals, the updated language provides clearer reference points for assessing occupational diving operations and identifying when SCUBA use, reduced crews, or inadequate planning may create unacceptable risk.

For insurers and risk managers, the changes provide a clearer basis for asking whether a diving operation has been properly classified, properly crewed, and properly planned.

Supporting National Harmonization

CADC says the upcoming changes also reinforce the need for national harmonization of occupational diving safety requirements across Canada.

The CSA Z275 Dive Standards are nationally developed and maintained through a consensus-based standards process involving subject-matter experts. CADC supports recognition and adoption of the CSA Z275 Dive Standards as the minimum occupational diving safety framework across all provinces and territories.

“Canada should not have occupational diving safety interpreted differently from one jurisdiction to another,” Elsey said. “The CSA Z275 Dive Standards provide the national safety floor. The 2026 changes show why it is important for regulations and industry practice to stay aligned with the current national standard.”

CADC will continue to advocate for consistent recognition of the CSA Z275 Dive Standards as the foundation for occupational diving safety in Canada.

About CADC

The Canadian Association of Diving Contractors represents Canada’s occupational diving contractors and promotes the safe conduct of commercial diving operations through recognized standards, competent personnel, effective regulation, and professional industry practice.

CADC members are expected to comply with applicable occupational health and safety legislation and the CSA Z275 Dive Standards as the minimum safety baseline for occupational diving operations.

Media Contact

Doug Elsey, P.Eng.
Executive Director
Canadian Association of Diving Contractors
Email: Delsey@CADC.CA
Phone: 905-542-7410

Disclaimer

This release is provided for general information only and does not constitute legal, regulatory, engineering, or occupational health and safety advice. Readers should consult the final published standard, applicable legislation, regulations, and the authority having jurisdiction. CADC does not certify, inspect, audit, or verify compliance by any person, company, contractor, employer, or diving operation.