Safety & Workplace Practices
Lockout/tagout procedures, ladder safety, scaffolding, confined spaces, PPE requirements, WHMIS, and fire safety fundamentals.
- Explain the purpose and correct procedure for Lockout/Tagout (LOTO)
- Identify sources of hazardous energy in HVAC systems
- Calculate correct ladder placement using the 4:1 rule
- Describe confined space entry requirements and atmospheric testing
- Select appropriate PPE for HVAC tasks including refrigerant handling
Lesson 1
Red Seal Program Framework & LOTO Procedures
Red Seal Occupational Standard (RSOS)
The Red Seal (Interprovincial Standards) program certifies tradespeople across Canada and allows certified workers to have their qualifications recognized in any province or territory without additional examination. For the Refrigeration and Air Conditioning Mechanic trade, the exam is now aligned to the Red Seal Occupational Standard (RSOS) - the framework that replaced the former National Occupational Analysis (NOA).
RSOS Replaced the NOA
The RSOS (Red Seal Occupational Standard) for Refrigeration and Air Conditioning Mechanic defines the blocks, lines, and competencies that structure the current IP exam blueprint. If you have older NOA study materials, replace them with RSOS-aligned resources. Exam questions are now mapped to specific RSOS learning outcomes - studying those outcomes directly tells you what will be tested. Download the current RSOS for your trade from the Red Seal Program website (ESDC/JTIP).
The RSOS organizes trade knowledge into blocks (major areas) and lines (groups of tasks within each block). The weighting of each block on the exam reflects the RSOS task importance ratings. Key blocks for the Refrigeration and Air Conditioning Mechanic trade include:
- Safety and Trade Practices
- Refrigeration Systems and Refrigerants
- Electrical Systems and Controls
- Heating Systems
- Air Distribution and Ventilation
- Troubleshooting and Diagnostics
Why LOTO Matters
Every year, HVAC technicians are injured or killed by unexpected equipment startup during service. Lockout/Tagout (LOTO) is the single most important safety procedure you will use throughout your career. The Red Seal exam tests LOTO knowledge extensively because it is foundational to every maintenance and repair task.
LOTO protects workers from the unexpected release of hazardous energy. In HVAC systems, hazardous energy comes from multiple sources simultaneously, making thorough lockout procedures critical.
Sources of Hazardous Energy
The exam will ask you to identify sources of hazardous energy. In HVAC work, all of the following are sources of hazardous energy:
Energy Sources in HVAC
Electrical - motors, contactors, control circuits, capacitors
Hydraulic - chilled water systems, hydronic piping
Pneumatic - compressed air systems, refrigerant pressure
Thermal - steam lines, hot water, heated surfaces
Mechanical - rotating shafts, belt drives, fans
Chemical - refrigerants, combustion gases
LOTO Steps
1. Notify all affected personnel
2. Shut down equipment using normal procedures
3. Isolate ALL energy sources
4. Apply personal lock and tag
5. Verify zero energy state
6. Perform work safely
The LOTO Procedure
Each worker servicing equipment must apply their own personal lock and tag. No two workers share a lock. The lock physically prevents energy isolation devices from being re-energized. The tag identifies who placed the lock and why.
Before beginning work, you must verify zero energy state by attempting to start the equipment. Simply turning off a switch is not enough - you must confirm that all stored energy has been dissipated, including capacitors that may hold electrical charge and pressurized lines that may contain refrigerant or compressed air.
When the exam asks about sources of hazardous energy in LOTO, the answer includes electrical, hydraulic, and pneumatic - all of the above. Every HVAC system contains multiple energy sources that must all be isolated before service.