ASI Group

Commercial Diving

ASI is proud to employ commercial dive crews who are professional, experienced and adhere to the highest standards in Health & Safety.

Commercial diving operations are a fundamental element in support of underwater infrastructure. This includes construction, maintenance and refurbishment of underwater infrastructure as well as inspections and assessments. Industries that rely on underwater assets look to commercial divers to provide visual and tactile information of assets below the waterline. These industries include power generation, oil and gas, municipalities, and manufacturing.

To be a successful commercial diver means to be a jack-of-all trades, possess problem solving capabilities and adhere to a strict safety culture. They follow the most up-to-date standards and regulations for commercial diving, ensuring safety is first in-mind. A commercial dive teams’ responsibility ranges from preparing health & safety plans, conducting risk assessment and mitigation strategies, to safely completing underwater works.


Commercial Diving - ASI Group
Play Video

ASI dive crews are supported by our surveying division and have access to remotely operated vehicles (ROV). For inspection and assessment projects, ASI promotes the use of technology to enhance project efficiency. ROV’s can conduct components of inspections where environmental factors could impose risk, or limitations to a diver.

ASI is committed to providing our clients with a multitude of in-house services with professionally trained and experienced divers and crews, in the safest way possible. Personnel are commercially certified in accordance with the accredited Diver Certification Board of Canada (DCBC), and in accordance with all relevant provincial and federal regulations and requirements.

ASI Commercial Diving Services include, but are not limited to:

  • Construction
  • Inspection, maintenance and repair
  • Nuclear diving
  • Ship Husbandry
  • Hyperbaric Intervention for tunneling construction
  • Deep (Air diving) Surface Decompression


Installation of new intakes and outfalls, bridge and dam construction support, building and installation of bulkheads and cofferdams, installation of traveling screens, installation of wharf and dock fenders, building pumphouses, valve installations, shoreline refurbishment and protection, erosion control of seawalls and stop log installations.

Inspection, Maintenance & Repair

Inspection and repair of culverts, retaining walls, bridges, ports & piers, docks, dams, pumphouse and piping stations, intake and outfalls and underwater containment. Annual baseline inspections to monitor degradation of equipment and infrastructure, in-water ship inspections and repairs, underwater welding, non-destructive testing (ultra-thickness measurements). Maintenance including irradiated diving for projects in nuclear facilities, bridges, ports and piers, zebra mussel cleaning, debris removal and reservoirs.

Nuclear Diving

ASI provides underwater maintenance services for nuclear facilities and ensures the necessary procedures and plans are in place to protect the safety of the divers, crew and facility while working in radiological environments. ASI is committed to the radiation safety principal ALARA (as low as reasonably achievable) and operates under strict Quality Control & Assurance guidelines.

Since 1987, ASI Marine has been a leader in commercial and nuclear diving, having developed world-first techniques and services that have improved safety and equipment reliability. In turn, this has led to the reduction of workload in nuclear plants and other industrial sites with underwater infrastructure.

Ship Husbandry

ASI provides inspection and repairs for ships within the Great Lakes, British Columbia and abroad. ASI is certified under five different classes (Lloyds, Rina, ABS, BV, DNV) and capable of performing surveys and repairs to extend time between dry-docking visits. To perform repairs, ASI divers are certified Lloyd’s Class underwater welders and provides 24/7 underwater maintenance services. The ASI team possesses in-depth knowledge and experience working within the shipping industry to efficiently carry out tasks and provide a cost-effective solution.

Fleet Services includes

  • Class approved I.W.S (In-Water Inspections)
  • Hull cleaning/propeller polishing
  • Propeller repair (hydrodynamic balancing, replacement of CP blades and blade seals)
  • Class certified underwater welding
  • Shell repairs – emergency and permanent
  • Ballast water inspection

Hyperbaric Intervention for Tunneling Construction

ASI’s experienced personnel are equipped with the required technology, specialized equipment and practical proven methodologies to support hyperbaric intervention needs on tunnel construction projects. Preparedness is undertaken by understanding all the projects’ requirements, executing detailed planning, and ensuring the safest methodologies, best practices and approved processes are in place.

Complex repairs can be successfully performed under pressure in hyperbaric environments, from planned maintenance inspections and cleaning, to complete tooling replacement and/or reconfiguration. Additionally, complex cutter header repairs utilizing structural hyperbaric welding can be undertaken with success.

Deep (Air diving) Surface Decompression

ASI has hyperbaric chambers to support decompression diving which allows the divers to maximize bottom-time. In Ontario this permits dives beyond 100 ft. as per the Ministry of Labor to expedite diving projects.

ASI also provides project planning and preparation by a robust team of experienced and professional personnel. The dive division consists of a Vice-President, Group Manager, Project Managers, Operations Managers, Superintendents, Supervisors and Divers. ASI maintains a minimum 25 full-time and part-time divers to meet on-going contractual obligations as well as emergency work.

As every project and client need is different, ASI commercial divers require a unique and diverse skill set. ASI commercial divers provide underwater welding and burning, nuclear diving and installation of traveling screens, heavy construction and inspection and repair services. ASI’s in-house training facility and programs ensure that divers are well-prepared to successfully complete projects in the most safe and efficient manner.

“Our client said that ASI was one of the most professional dive operations they had seen.” – GEI

ASI projects start with the Project Manager who reviews the project scope in detail and ensures a thorough understanding of client requirements. Health & Safety and risk mitigation strategies are considered from the get-go. A minimum 4-man dive crew is then assembled in accordance with CSA Z275.2 standard for Occupational Safety Code for Diving Operations which include a diving supervisor, primary diver, dive tender and stand-by diver. ASI upholds itself to the highest safety standards. For projects in British Columbia, ASI adheres to WorkSafe BC Health and Safety Regulations.

ASI plans diving rotations to suit project requirements and increase productivity and integrity of safety.

Before ASI divers arrive on the project site, project preparation starts in the ASI shop. Typical diver gear consists of air tanks, helmets, dry suits, weight belts. Project specific equipment includes compressors, welders, hydraulic packs, pumps, specialty underwater tools such as concrete and rock drills, coring drills, chippers and breakers, chain saws and concrete saws. Equipment for each project is carefully selected and prepared by the diving supervisors. Safety meetings are ensued at project site and client safety training is completed before the project commences. ASI maintains best industry practices for routine equipment functionality.

Evoqua-trained Service Crews

Evoqua Water Technologies and ASI together offer turnkey intake solutions to the Canadian market. Evoqua provides the intake industry nearly 150 years of market-leading design, manufacturing and service of intake equipment. ASI delivers unparalleled commercial diving expertise combined with an exceptional safety record. Their exclusive collaboration provides a single point of contact for a uniquely comprehensive portfolio of products and services.

Aging underwater infrastructure requires extended inspection, repair and maintenance activities to prolong its operational life. This includes structural and conditional inspections, mechanical modifications and repairs, welding repairs, coating applications and decommissioning tasks.

When safe to do so, commercial diving services can be more economical than dewatering. Specialized commercial diving procedures have been used internationally for over 20 years.

At ASI, safety is the overriding priority

ASI’s health & safety team works closely with departments to ensure health & safety plans are up-to-date and risk mitigation processes are followed. ASI is registered to ISO 9001:2015 for Quality Management Systems and ISO 45001 for Occupational Health & Safety. Additionally, third part vendor qualification consultants review ASI’s current policy and program. These consultants belong to Avetta, Cognibox, Complyworks and ISNetworld. ASI has maintained an outstanding safety record in a high-risk profession and prides itself on exceptional safety policies resulting in no serious diving related injuries over its 30-year history.

ASI is accredited to the following governing bodies:

  • CADC
  • ADCI
  • PDI
  • Ontario Infrastructure Guides
  • Lloyds

Before each dive, the Diving Supervisor will ensure that a dive plan has been formulated and all persons involved with the operation have been briefed of the following:

  • the hazards that may be encountered during the dive
  • the intended duration of the dive and the maximum depth to be reached
  • the tasks or assignments of every person involved, including the diver and sonar team
  • specific operational parameters and/or recall signals
  • emergency procedures, recovery and evacuation plan
  • energy isolation (lock-out tag-out)
A commercial diver entering the water

ASI personnel prepare field inspection reports recording all relevant data for further client review. Final reports outline the diver inspection in detail, supplemented by assessments and can include required repair works and budgets and residual life estimates conducted by ASI’s dive engineers. Relevant photo images, Dive/ROV video footage and referenced drawings are provided as part of the report.



Is diving safe?
  • Yes, ASI management is actively involved in shaping the safety culture across the country. We are voting members for the CSA Occupational Safety Code for Diving Operations and CSA Diving Competency Standards and the IHSA Commercial Diving Committee.
Are your Divers certified?
  • All of our divers have attended an accredited commercial diving institute and are certified by the Diving Certification Board of Canada (DCBC). Our underwater welders hold current tickets certified by Lloyd’s Registrar for underwater ship repairs.
When can you dive (seasons)?
  • Our divers operate all year. The divers utilize various insulations depending on the water temperatures to stay comfortable.
How deep can you dive?
  • An unrestricted surfaced supplied diving certification allows air diving up to 165-feet of water. Typically, in the great lakes, the majority of work is in 60-feet or less.

ASI Marine’s commercial diving crews conduct a full range of underwater services, including;

Contact us to learn more about our services

+1 905-643-3283
For immediate assistance, please contact our Head Office at the number above.