How the code is organized

On the second evening Moira handed out a blank sheet and asked the class to draw the code from memory: its parts, their order, and where they would look for the rules on a hydraulic elevator's pit, an escalator's brake and a rope replacement. Nobody got it all right, and that was the point. “The code is more than five hundred pages,” she said. “You will never memorize it, and you do not need to. You need a map in your head that gets you to the right section in a minute, and the habit of reading the section once you get there.” This lesson is that map: the parts of the code, how the sections and clauses are numbered, what the appendices and tables are for, how editions and interpretations work, and how one part of the code borrows from another.

The parts of the code

The code is divided into parts by type of equipment, followed by general parts that apply to everything. Part 1 holds the scope, the purpose and the definitions. Part 2 covers electric elevators, meaning traction and drum machines, and it is the largest and most detailed part: most of the basic requirements for hoistways, machine rooms, doors, cars, safeties, governors, ropes, buffers, machines and controls are written here. Part 3 covers hydraulic elevators, Part 4 elevators with other kinds of driving machines such as rack-and-pinion and screw-column machines, and Part 5 special-application elevators, including inclined elevators, limited-use and limited-application elevators, private residence elevators and elevators used during construction. Part 6 covers escalators and moving walks, and Part 7 dumbwaiters and material lifts.

Part 8 applies to all of these. It contains the general requirements that do not belong to one kind of equipment: security of machine rooms and hoistways, design data and formulas, engineering and type tests and the certification of components, seismic requirements, maintenance, repair and replacement, alterations, welding, the code data plate, and the acceptance and periodic inspections and tests. Part 9 lists the other standards the code refers to, with the editions it relies on. When you are on site, it is very often Part 8 you need, because Part 8 tells you what must happen when existing equipment is maintained, repaired, replaced or altered.

Part 2 section by section

Because Part 2 sets the pattern, Tamsin learned its section order first. It runs roughly in the order an elevator is built: the hoistway and its enclosure, the pit, the location and guarding of counterweights, vertical clearances, runbys and refuge spaces, horizontal clearances, the machinery spaces and machine rooms, the equipment allowed in hoistways, machinery supports and guarding, the hoistway door openings and their locking devices, power-operated doors, the car enclosure and car doors, car frames and platforms, capacity and loading, safeties, governors, ascending car overspeed and unintended movement protection, suspension means, counterweights, buffers, guide rails, driving machines and sheaves, terminal stopping devices, operating devices and control equipment, emergency operation and signaling devices, layout data, and finally the identification of equipment.

How clauses are numbered

Every requirement has an address. The first number is the part, the second the section within the part, and further numbers narrow down to a requirement, a clause and a subclause, with letters and roman numerals for the lowest levels. In a reference such as 2.27.3.1, the 2 is Part 2, electric elevators; 2.27 is the section on emergency operation and signaling devices; 2.27.3 is the requirement for firefighters' emergency operation; and 2.27.3.1 is the clause on Phase I recall. Tables and figures are numbered after the clause that uses them, such as Table 2.16.1.1 for the capacity table. Once you know this pattern, a clause number tells you where you are in the book before you have read a word of it.

# Decode a code reference into its part, section and requirement
parts = {"1": "general", "2": "electric elevators", "3": "hydraulic elevators",
         "4": "elevators with other types of driving machines", "5": "special application elevators",
         "6": "escalators and moving walks", "7": "dumbwaiters and material lifts",
         "8": "general requirements", "9": "reference codes and standards"}
sections = {"2.2": "pits", "2.4": "vertical clearances and runbys", "2.7": "machinery spaces and machine rooms",
            "2.16": "capacity and loading", "2.18": "speed governors", "2.27": "emergency operation and signals",
            "3.18": "hydraulic jacks", "8.6": "maintenance, repair, replacement and testing", "8.7": "alterations",
            "8.10": "acceptance inspections and tests"}
def decode(ref):
    main = ref.split("(")[0]
    bits = main.split(".")
    part = bits[0]
    sec = ".".join(bits[:2])
    depth = {2: "section", 3: "requirement", 4: "clause"}.get(len(bits), "subclause")
    print(f"{ref}: Part {part} ({parts[part]}), section {sec} ({sections.get(sec, 'see the contents')}), a {depth}")
for r in ["2.27.3.1", "8.7.2.17", "3.18.3", "2.4.12.1(a)", "8.10.2"]:
    decode(r)

2.27.3.1: Part 2 (electric elevators), section 2.27 (emergency operation and signals), a clause
8.7.2.17: Part 8 (general requirements), section 8.7 (alterations), a clause
3.18.3: Part 3 (hydraulic elevators), section 3.18 (hydraulic jacks), a requirement
2.4.12.1(a): Part 2 (electric elevators), section 2.4 (vertical clearances and runbys), a clause
8.10.2: Part 8 (general requirements), section 8.10 (acceptance inspections and tests), a requirement

The section titles in Tamsin's decoder are her own short versions; the code's titles are longer. The decoder is crude, but it makes the point Moira wanted: a reference to 8.7 is always about alterations, and a reference that starts with 3 is always hydraulic, before you open the book.

Cross-references and borrowing

The later parts of the code do not repeat everything in Part 2. A hydraulic elevator needs a hoistway, a pit, hoistway doors and interlocks just as an electric elevator does, so Part 3 says, in effect, that the hoistway shall conform to the Part 2 requirements, with listed exceptions and additions. The same happens in Parts 4, 5 and 7. This saves hundreds of pages, but it means that a hydraulic or special-application requirement often lives in two places: the Part 2 clause that sets the rule and the later clause that modifies it. When Tamsin looked up the pit requirements for the Marlowe hydraulic, she found the Part 3 clause first, followed its reference back to Part 2, and then came back to Part 3 to read the exceptions. Reading only one of the two would have given the wrong answer.

Cross-references also run outward to other standards. The code relies on the electrical code for wiring, on building codes for fire separations and structure, on welding standards for welded parts, on accessibility standards for controls and signals, and on many material and test standards listed in Part 9. When a clause says that something shall conform to another standard, that standard becomes part of the requirement, but usually only for the subject the clause names, and usually in the edition Part 9 lists unless the regulation says otherwise.

Appendices, tables and the Canadian clauses

After the parts come nonmandatory appendices. They contain explanations, sample forms, diagrams and recommended practices, such as guidance on control system evaluation, sample maintenance records, or drawings that show how clearances are measured. They are useful, but as lesson 1 said, they are not requirements unless a jurisdiction makes them so. Some jurisdictions do exactly that for selected appendices; some jurisdictions make an appendix mandatory, and Washington's rules include local amendments of this kind. Tables in the body of the code are requirements, and many of the numbers a mechanic uses, such as rope factors of safety, governor tripping speeds and capacity, come from them.

A few clauses apply only in Canada or only outside Canada. In the harmonized text they are introduced by phrases such as “in jurisdictions enforcing the NBCC” or “in jurisdictions not enforcing the NBCC,” where NBCC is the National Building Code of Canada. They usually deal with things the two countries' building codes treat differently, such as fire service signals, standby power and some construction details. In Washington the clauses for jurisdictions not enforcing the NBCC apply; the Canadian versions can be skipped.

Editions, interpretations and the handbook

The code is reissued on a regular cycle, recently every three years, with editions such as 2016, 2019, 2022 and 2025. Each edition lists its changes, and older editions were sometimes updated with addenda between full editions. Because jurisdictions adopt editions at different times, and because equipment is usually held to the edition in force when it was installed or altered, a mechanic in one city may work to three or four editions in a single week. Always check which edition you are reading and which edition applies.

When the meaning of a requirement is unclear, anyone can ask the code committee for an interpretation. Published interpretations answer a specific question about a specific edition, and they are often the clearest statement of what a clause means. The committee also issues cases, which allow an alternative to a requirement under stated conditions until the code itself is revised. Commentary books written to explain the rationale behind each requirement are helpful for study, but they are not part of the code. On site, the authority having jurisdiction makes the final decision about how the adopted code applies.

Using the code on site

Moira finished the evening with the way experienced mechanics actually use the code on a job. Few carry the whole book into a hoistway. Instead they work from three things: the inspection guide's checklists, which follow the code's order and point to its clauses; the maker's manuals, which say how each device is adjusted and tested; and a short list of the clauses that matter most for the work in hand, written out before the job starts. When a question comes up that the list does not answer, they go back to the full text, in the right edition, and read the whole clause with its exceptions and definitions. Moira's advice was to keep a marked-up personal copy of the edition used most in the area, with tabs at the sections that come up again and again: definitions, Part 2's clearance, door, safety and control sections, and Part 8's maintenance, alteration and test sections.

Tamsin made a one-page map of the book for her notebook, with the parts down the side and, against each, the courses in which she had already used it. It showed something she had not noticed: almost everything she had done in three years came from Part 2 and Part 8, with Parts 3 and 6 for the hydraulic and escalator terms. Most mechanics, Moira said, spend their working lives in the same few hundred pages.