4AE3 U3 C3 Obj 3.pdf

Unit A-3 • Introduction to Power Engineering and its Governance in Canada Objective 3 Explain the content and use of the CSA B52 Mechanical Refrigeration Code. The CSA B52 Mechanical Refrigeration Code is revised every 3 to 5 years. Therefore, always refer to the most current Code identified on th...

Unit A-3 • Introduction to Power Engineering and its Governance in Canada Objective 3 Explain the content and use of the CSA B52 Mechanical Refrigeration Code. The CSA B52 Mechanical Refrigeration Code is revised every 3 to 5 years. Therefore, always refer to the most current Code identified on the CSA website. The code sections relevant to Power Engineers can be found in the PanGlobal Extract of CSA Standards. According to CSA, the B52 Code was developed to “minimize the risk of personal injury by providing minimum requirements for the design, construction, installation, inspection, and maintenance of refrigeration systems.” CSA B52 - Mechanical Refrigeration Code Like CSA B51, a committee called the Technical Committee on Mechanical Refrigeration Code produces the B52 Code. The committee consists of representatives from: • Provincial and territorial jurisdictions • Professional engineers’ associations • Refrigerating and air conditioning institutes • Other interested groups The CSA B52 has two purposes. 1. It provides for the safe design, construction, installation, operation, and repair of refrigerating and air conditioning equipment and systems, and related equipment. 2. It promotes uniform requirements among the provinces and territories. 1 - Scope The scope lists the type of equipment to which this code applies, as well as the equipment to which it does not apply. 2 - Reference Publications This section lists all of the publications referred to by CSA B52. 3 - Definitions and Abbreviations This section lists and defines terms related to refrigeration and air conditioning equipment. 4 - System Selection and Application Requirements The requirements for system selection and application are discussed. It also includes the various system classifications. 3-10 4th Class Edition 3 • Part A Codes and Standards for Power Engineers and Pressure Vessels • Chapter 3 Occupancy Classification This part of the code defines five different building occupancies. They include: 1. Commercial 2. Institutional 3. Industrial 4. Residential 5. Public assembly Refrigerating System Classification Refrigeration systems are classified by the method used for extracting heat (e.g. direct, double direct and indirect). Each classification is described. Sketches are given to assist in these descriptions. Refrigerant Classification Based on toxicity and flammability, the refrigerants used are listed and divided into six safety groups. Group 1 refrigerants are the least flammable. Group 3 refrigerants are the most flammable. Group A refrigerants are the least toxic. Group B refrigerants are the most toxic. Therefore, refrigerants are grouped into A1, A2, A3, B1, B2, or B3. 5 - Equipment Design and Construction This section is extensive. It deals with drawings, specifications, and data reports for refrigeration pressure vessels, piping and fittings. Parts of section 5 refer the user to relevant CSA B51 code section. As well, this section discusses: • • • • • Minimum design pressures Materials of construction Provisions necessary for servicing Pressure testing Nameplate requirements 6 - Installation This section primarily covers the requirements for machinery rooms. • • • • • • • • Refrigerant leak detection systems Ventilation systems Fire ratings Electrical ratings Duct work Provision for safe egress Location of piping, piping supports Emergency discharge systems 7 - Overpressure Protection This section lists the regulations regarding pressure vessel and compressor overpressure protection. It also includes pressure limit controls and pressure relief valve installation. Pressure relief valve set points, capacities, and discharge piping are covered. As well, section 7 addresses rupture disk and fusible plug use for pressure relief. 4th Class Edition 3 • Part A 3-11 Unit A-3 • Introduction to Power Engineering and its Governance in Canada 8 - Maintenance of Systems These are the rules for charging and discharging refrigerants, system maintenance, and posting of instructions. 9 - Precautions These rules refer to the jurisdictional requirements for personal protective equipment, such as breathing apparatus. It also covers the special egress hazards of enclosed refrigerated spaces. 3-12 4th Class Edition 3 • Part A