29 CFR 1910.269(r): the three tiers, and what each one may approach

29 CFR 1910.269 recognizes three tiers. Qualified employees get the whole standard except paragraph (r)(1), and an approach distance the employer computes from Table R-3. Line-clearance tree trimmers who are not qualified employees get eight listed paragraphs plus all of (r), and read Table R-6 directly. Unqualified employees owe 10 feet under Subpart S.

Three people park under the same 12 kV distribution feeder on a Tuesday morning. One holds a line-clearance card and is going up the tree. One was hired six weeks ago and is running the chipper. One is a general foreman who also works substation clearances and is there to look at a pole.

The conductor above them is a single conductor at a single voltage. The distance each of the three owes it is not the same number, it is not set by the same paragraph, and only one of the three is allowed to touch anything energized at all. Sorting them is the first thing that happens on that job, and getting it wrong is what turns a routine trim into a fatality investigation.

29 CFR 1910.269 does the sorting. It is worth knowing where, because it is not where most people look.

Paragraph (r), and the sentence that sorts the crew

Paragraph (r) opens by saying what it is for: "This paragraph provides additional requirements for line-clearance tree trimming and for equipment used in this type of work." Then comes (r)(1), headed Electrical hazards, and its second sentence is eight words long: "This paragraph does not apply to qualified employees."

That sentence is the whole tier system in miniature. Everything in (r)(1), the voltage determination before climbing, the second trimmer within voice range, the insulating equipment for branches inside the distance, the limit on how close a ladder or bucket may come, exists for people who are not qualified employees. A qualified employee is not exempt from those hazards. A qualified employee is exempt from that paragraph because paragraph (l) already imposes a stricter regime covering the same ground.

The rest of paragraph (r) is not tiered at all. Paragraphs (r)(2) through (r)(8) cover brush chippers, sprayers, stump cutters, gasoline-engine power saws, backpack power units, rope and fall protection, and they bind everyone doing this work inside the section's scope. A qualified employee who climbs still owes (r)(8): tied in with a climbing rope and safety saddle whenever working above the ground in a tree, unless ascending into it.

The rope still has to meet (r)(7)(i), which sets a minimum diameter of 12 millimeters (0.5 inch), a minimum breaking strength of 10.2 kilonewtons (2,300 pounds), and, for synthetic rope, elasticity of not more than 7 percent. Those are numbers a supervisor can check against a spool tag in about ten seconds, and they do not move with anyone's qualification.

The version of the standard that says all this took effect with the final rule published at 79 FR 20633 on April 11, 2014, and the section has been amended five times since, most recently at 85 FR 8732 on February 18, 2020. Anything written about 1910.269 before April 2014 is describing a different table scheme, and a good deal of the training material in circulation still is.

Where the tiers are written, and the one by omission

Paragraph (r) does not define the tiers. The scope paragraph does, at 1910.269(a)(1)(i)(E), and it only defines two of them.

Subparagraph (E) first fixes what work is in scope. Two conditions, both of which have to hold.

• The work is line-clearance tree trimming performed for the purpose of clearing space around generation, transmission or distribution lines or equipment.

• It is performed on behalf of an organization that operates, or controls the operating procedures for, those lines.

Then it splits:

(E)(1). "Entire § 1910.269, except paragraph (r)(1) of this section, applies" when the work is performed by qualified employees.

(E)(2). "Paragraphs (a)(2), (a)(3), (b), (c), (g), (k), (p), and (r) of this section apply" when the work is performed by line-clearance tree trimmers who are not qualified employees.

Eight paragraphs out of twenty-four. Training, information transfer between host and contract employers, medical services and first aid, job briefing, personal protective equipment, materials handling and storage, mechanical equipment, and all of paragraph (r). What is not on that list is as informative as what is. Paragraph (d), hazardous energy control, is out.

Paragraph (l), working on or near exposed energized parts, is out, which is the point: a line-clearance tree trimmer who is not a qualified employee never works on an energized part, so the paragraph that governs doing so does not reach them. Paragraph (n), grounding, is out. So is (q), overhead lines and live-line barehand work.

One omission is worth watching, because it comes back in sideways. Paragraph (a)(4), Existing characteristics and conditions, which requires the nominal voltages, switching transients, induced voltages, pole condition and the rest to be determined before work starts, is not on the (E)(2) list. But (c) is, and (c)(1)(i) requires the employer to give the employee in charge "all available information that relates to the determination of existing characteristics and conditions required by paragraph (a)(4)."

The duty arrives at the tailboard through the job briefing rather than through (a)(4) directly. For a contract line-clearance company the companion duty is (a)(3)(i), which puts the burden on the host utility to inform the contractor of the characteristics of its installation before work begins. The return duty is (a)(3)(ii)(C): the contractor has two working days to report back any unanticipated hazardous condition it finds.

The third tier is not in (E) at all. It is defined by falling out of it. OSHA's line-clearance tree trimming eTool names all three plainly, in guidance the standard itself never bothers to write down: "OSHA recognizes three different qualification levels for line-clearance tree trimmers: Unqualified employees … 269-qualified employees … Line-clearance tree trimmers."

On the first of those the eTool is explicit: "Section 1910.269 does not apply to tree trimming operations performed by unqualified employees," whose work practices sit under Subpart S and particularly 1910.333(c)(3). That is OSHA reading its own standard, and the reading follows from the text: (E)(1) covers qualified employees, (E)(2) covers line-clearance tree trimmers, and a person who is neither is covered by neither.

For the six-week ground worker running the chipper, that is the answer. Nothing in 1910.269 sets that person's approach distance. 1910.333(c)(3) does.

Five competencies, three competencies, and the two that go missing

Both remaining tiers are defined by a training list, and the two lists sit ten lines apart.

1910.269(a)(2)(ii) gives the qualified employee five items:

• Distinguishing exposed live parts from other parts of electric equipment.

• Determining the nominal voltage of exposed live parts.

• Knowing and maintaining the minimum approach distances for the voltages involved.

• The proper use of precautionary techniques, protective equipment, insulating and shielding materials and insulated tools for work on or near exposed energized parts.

• Recognizing electrical hazards along with the skills to control or avoid them.

The note underneath makes the list constitutive rather than advisory: a person must have that training to be a qualified person under the section.

1910.269(a)(2)(iii) gives the line-clearance tree trimmer who is not a qualified employee three items, and they are the first three of the five, in the same order.

So the difference between tier two and tier three is not a matter of degree spread across five subjects. It is two whole subjects, and they are items (D) and (E): how to use insulating and shielding equipment on or near energized parts, and how to recognize electrical hazards generally. Everything the higher tier is permitted to do that the lower tier is not runs through those two items. Rubber gloving is item (D). Judging an unfamiliar configuration on a pole is item (E).

That is why the definitions section, at 1910.269(x), can afford to define a line-clearance tree trimmer loosely: "An employee who, through related training or on-the-job experience or both, is familiar with the special techniques and hazards involved in line-clearance tree trimming." No months, no hours, no certifying body, no expiry.

The definition is loose because (a)(2)(iii) is doing the work, and (a)(2)(iii) is a list of three checkable subjects. California takes the opposite approach and puts a clock in its definition instead; how the 18 months in 8 CCR 2700 does and does not settle the question is a separate matter, decided by a separate body.

A practical consequence: a 40-hour line clearance course certificate tells you the graduate sat through a curriculum. It does not by itself tell you which of the two lists the employer used, and the lists are what the standard asks about. The certificate that matters is the one that names subjects.

Three people, one 12 kV conductor, three distances

Back to the feeder. Nominal 12 kV, three phases, everyone at sea level.

The ground worker. 1910.333(c)(3)(i)(A) puts an unqualified person in an elevated position, and the longest conductive object that person may contact, no closer than 10 feet to any unguarded energized line at 50 kV or below. 1910.333(c)(3)(i)(B) applies the same distance to anyone on the ground bringing a conductive object toward the line. A 12-foot pole pruner handed up from below is a conductive object. The 10 feet is measured from the end of it, not from the person holding it.

The climber. 1910.269(r)(1)(iii) sends a line-clearance tree trimmer to the tables. Table R-6, Alternative Minimum Approach Distances for Voltages of 72.5 kV and Less, prints 0.65 meters (2.14 feet) for phase-to-ground exposure in the 5.1 to 15.0 kV band and 0.68 meters (2.24 feet) for phase-to-phase. On a 21 kV circuit, one band up, the figures are 0.77 meters (2.53 feet) and 0.89 meters (2.92 feet).

That number does not travel alone. 1910.269(r)(1)(ii)(A) requires a second line-clearance tree trimmer within normal, unassisted voice communication as soon as the climber goes closer than 10 feet to anything energized at more than 750 volts. Between 10 feet and 2.14 feet there is nearly eight feet of approach in which the trimmer is outside the minimum approach distance and inside the two-person rule.

Paragraphs (r)(1)(ii)(B) and (C) add the same requirement whenever limbs being removed are closer to the conductor than the table distance, or whenever roping is needed to take them off it. And under (r)(1)(iv), any branch already contacting an energized conductor, or inside the table distance, may be removed only through the use of insulating equipment.

The foreman. As a qualified employee the foreman is out from under (r)(1) entirely and under paragraph (l) instead. 1910.269(l)(3)(i) does not hand out a distance; it requires the employer to establish one, no less than the distance computed by Table R-3.

For 5.1 to 72.5 kV that computation is MAD = M + AD, where M is a fixed inadvertent movement factor of 0.61 meters, A is the Table R-5 altitude correction factor, and D is the electrical component from Table R-4. At 12 kV phase-to-ground, D is 0.04 meters and A at sea level is 1.00, so the answer is 0.65 meters. The same number the climber gets off Table R-6, because Table R-6 is that computation already performed.

The tier does not change the distance at 12 kV. It changes everything around it. Under 1910.269(l)(1)(i), only a qualified employee may work on or with exposed energized lines at all. Under (l)(3)(iii), only a qualified employee has a route inside the established distance.

It opens only where the employee is insulated from the energized part, where the part is insulated from the employee and from other conductive objects at different potential, or where the live-line barehand conditions of (q)(3) are met. The climber has no equivalent escape. For the climber, 2.14 feet is a wall.

There is one place the higher tier gets the vaguer rule. The climber's two-person requirement is a bright line: 10 feet, 750 volts, a second line-clearance tree trimmer, voice range. The foreman's comes from (l)(2).

Its list of operations requiring two employees names installation, removal and repair of lines and equipment, and then catches everything else at (l)(2)(i)(E), which asks whether the work exposes an employee to electrical hazards greater than or equal to those listed. Tree trimming is not named. Whether a given trim clears that bar is the employer's call in the first instance, and a compliance officer's on inspection.

At 5,000 feet the two routes stop agreeing

Take the same feeder up into the Sierra. The crew is at 1,524 meters, which is 5,000 feet, and Table R-5 gives an altitude correction factor of 1.08 for the 1,501 to 1,800 meter band.

Now the two routes diverge, because they apply that factor to different things.

Table R-3 multiplies only the electrical component: MAD = 0.61 + (1.08 x 0.04) = 0.6532 meters. The inadvertent movement factor is not altitude sensitive and does not get scaled. Footnote 1 to Table R-6 says something different. It permits the table only at 900 meters (3,000 feet) or below, and above that requires the employer to determine the distance "by multiplying the distances in this table by the correction factor in Table R-5." The whole distance, movement factor included: 0.65 x 1.08 = 0.702 meters.

Two people on the same span, on the same conductor, with 0.049 meters between their numbers. About two inches at 12 kV. On a 115 kV line the same footnote turns Table R-7's 1.13 meters (3.71 feet) into 1.22 meters (4.00 feet), and the gap widens with every band you climb, because the multiplier is applied to a larger printed figure.

This is not a drafting error, and it is not something an employer needs to resolve in OSHA's favor. Tables R-6 and R-7 are headed Alternative and are optional: 1910.269(l)(3)(i) requires distances "no less than" the computed values, and the alternative tables are deliberately conservative so that an employer can use them without running the arithmetic. The larger number landing on the less-trained tier is the right direction of travel.

What it means in practice is narrower and more useful. A crew working above 3,000 feet cannot write one minimum approach distance on the tailboard sheet for everybody without having chosen, silently, which of the two routes it used. If the sheet says 2.30 feet, that is the Table R-6 route and it covers both tiers with room to spare.

If it says 2.14 feet, that is the Table R-3 route and it is the correct figure for the qualified employee and short for the line-clearance tree trimmer. The employer establishes the distance under (l)(3)(i); the Division or the compliance officer tests that determination on inspection; the Review Commission, or in California the Appeals Board, resolves it if the citation is appealed. Write down which table the number came from and the question never opens.

Paragraph (r)(1) cites a table with no distances in it

Four times in paragraph (r)(1), at (ii)(B), (iii), (iv) and (v), the standard uses the same citation string: "Table R-5, Table R-6, Table R-7, and Table R-8." Paragraph (r)(1)(iii) is the operative one:

Line-clearance tree trimmers shall maintain the minimum approach distances from energized conductors given in Table R-5, Table R-6, Table R-7, and Table R-8.

Two of those four tables do not contain a minimum approach distance for this reader.

Table R-5 is headed Altitude Correction Factor. It is a two-column table of elevation bands and multipliers, 1.00 through 1.44, and there is not a distance anywhere in it. Table R-8 is DC Live-Line Minimum Approach Distance with Overvoltage Factor, which is a real distance table and has nothing to do with an AC distribution feeder. For an AC line the operative tables are R-6 below 72.5 kV and R-7 above it, with R-5 entering only as the multiplier that footnote 1 to each of those tables calls for.

Say plainly what this is: a citation string carried across the 2014 renumbering that now names more tables than it needs. It does not create an obligation nobody can perform, and no compliance officer is going to ask a crew to maintain an approach distance of 1.08.

But a trainer building a curriculum from the text of (r)(1)(iii), or a contractor writing a work method statement that quotes it, will produce a document listing four tables where two apply. An evaluator reading that document has no way to tell whether the author understood the standard or copied it. Cite R-6 or R-7 by voltage, name R-5 as the altitude multiplier, and leave R-8 out unless there is DC on the structure.

OSHA's own eTool still cites the table numbers from before 2014

The stale citations are not confined to the standard. OSHA's minimum approach distance eTool page currently tells readers that "The '269' standard identifies required Minimum Approach Distances (MAD) in Table R-6 (1910.269(l)(2))" and that "Table R-10 provides guidance for making altitude adjustments."

Check that against the standard as it stands. Paragraph (l)(2) is At least two employees; minimum approach distances are at (l)(3). Table R-6 exists but is the alternative table, not the computed one, and the paragraph that requires the computation points to Table R-3. There is no Table R-10 in 1910.269 at all; the altitude correction factor is Table R-5. The eTool is describing the pre-2014 numbering scheme, accurately for its time and no longer for the reader's.

That is worth knowing for two reasons. The first is defensive: anyone building a training deck or a safety manual from eTool citations is going to cite a paragraph that says something else, and the person who finds it will be an evaluator or a compliance officer rather than a colleague.

The second is that the same eTool is the only place OSHA states the three-tier framing in so many words, and that framing is sound even where the table numbers around it are not. Use the eTool for the structure and the standard for the citations.

OSHA's own position on where guidance sits relative to the standard is set out in its June 30, 2021 inspection guidance for tree care and tree removal operations. It directs compliance officers inspecting line-clearance work covered by 1910.269 to enforce the applicable provisions of the standard, and notes that citations may also be issued under the General Duty Clause where no standard applies. The tables that get cited in a citation are the ones printed in the CFR.

The 2014 renumbering was contested at the time, which is part of why so much material predates it. OSHA's December 22, 2016 enforcement memorandum on the minimum approach distance requirements records that the final rule issued on April 11, 2014. It also records a settlement agreement OSHA entered on February 13, 2015 with the Edison Electric Institute, the Utility Line Clearance Coalition and the Tree Care Industry Association. The line clearance industry was at that table by name.

One trimmer, qualified under one standard and not the other

This is the single most reliable source of confusion in the area, and the standard puts the answer in a note rather than in the body, which does not help.

Note 2 to the definition of line-clearance tree trimmer in 1910.269(x) says two things in consecutive sentences. First: a line-clearance tree trimmer "is not considered to be a 'qualified employee' under this section unless he or she has the training required for a qualified employee under paragraph (a)(2)(ii)." Then: "However, under the electrical safety-related work practices standard in subpart S of this part, a line-clearance tree trimmer is considered to be a 'qualified employee.'"

One person, two labels, opposite signs. The mechanism is the training lists. 1910.332(b)(3) sets three items a qualified person must be trained in under Subpart S: distinguishing exposed live parts, determining nominal voltage, and the clearance distances in 1910.333(c) with their corresponding voltages.

Those are the same three subjects as 1910.269(a)(2)(iii), differing only in which distance table they point at. The line-clearance tree trimmer clears the Subpart S bar because the Subpart S bar is set at three items, and falls short of the 1910.269 bar because that one is set at five.

When does the second label matter? 1910.331(c) takes work by qualified persons on or directly associated with generation, transmission and distribution installations out of Subpart S, and 1910.331(a)(2) confirms that line-clearance tree trimming covered by 1910.269 is such work. So on the utility's feeder, on the utility's behalf, Subpart S is not in play and 1910.269 governs.

But 1910.331(b)(2) pulls back in work performed by qualified persons near those installations when the work is not on or directly associated with them. The note to the definition of line-clearance tree trimming in 1910.269(x) says the same thing from the other direction: trimming performed on behalf of a homeowner or a commercial entity other than the line operator is outside the section.

Take the practical version. The same climber, on a Thursday, takes down a limb over a homeowner's driveway near that same 12 kV conductor. The climber is no longer under 1910.269 and no longer a line-clearance tree trimmer for the purposes of that standard.

Under Subpart S the climber is a qualified person, so the governing distance is Table S-5 at 1910.333(c)(3)(ii), which gives 2 feet 0 inches for over 2 kV up to 15 kV, and not the 10 feet that 1910.333(c)(3)(i) imposes on the unqualified. What that shift does and does not license, and what the employer has to have in place before relying on it, is the separate question of incidental line clearance work.

How a name gets into a tier, and who decides

The standard never asks for a card. It asks for a determination, and it says how the determination is made.

Training may be classroom or on-the-job under (a)(2)(vi), and must establish proficiency in the work practices and introduce the compliance procedures under (a)(2)(vii). The gate is (a)(2)(viii): the employer "shall ensure that each employee has demonstrated proficiency in the work practices involved before that employee is considered as having completed the training." Attendance is not completion. Demonstration is.

Note 1 to that paragraph is the one worth reading twice: employment records showing successful completion are "not required by this paragraph" and are "one way of keeping track of when an employee has demonstrated proficiency." The federal standard imposes no training record for line-clearance tree trimming. It imposes a determination, and leaves the employer holding the evidentiary problem of proving one was made. What that file should actually contain is the employer's design decision, not the standard's.

For a new hire who arrives already trained, Note 2 to (a)(2)(viii) supplies a three-step process the employer may use:

1. Confirm the employee has the training required by (a)(2). 2. Use an examination or interview to make an initial determination that the employee understands the relevant safety-related work practices before performing any covered work. 3. Supervise the employee closely until proficiency is demonstrated.

Three steps, three dates. A climber hired on March 2 with an out-of-state card and put on a bucket crew on March 3 has been through step one at most.

Two further obligations run continuously rather than once. Under (a)(2)(iv) the employer must determine, "through regular supervision and through inspections conducted on at least an annual basis," that each employee is complying with the required work practices. That is a yearly observation per employee, not a yearly toolbox talk.

And (a)(2)(v) triggers retraining where the annual inspection shows noncompliance, where new equipment or procedures change the practices involved, or where an employee must use practices not normally part of their duties. The note to (a)(2)(v)(C) turns the last of those into something close to a rule: OSHA "considers tasks that are performed less often than once per year to necessitate retraining before the performance of the work practices involved." Storm restoration work that a crew touches every other winter is squarely inside that note.

One consequence of the tier falls outside the approach distance entirely and is easy to miss. 1910.269(b)(1)(i) requires at least two first-aid trained persons available for field work involving two or more employees. The relief for line-clearance tree trimming by line-clearance tree trimmers who are not qualified employees drops that to one, but the relief is conditional: it applies "if all new employees are trained in first aid within 3 months of their hiring dates."

An employer running a one-trained-person crew on the strength of that sentence has taken on a hiring-date obligation for everybody, which is a payroll fact rather than a safety fact and is therefore usually filed somewhere nobody checks. The first aid and CPR requirements that attach to this work are worth reading as a set rather than as an exception.

What the federal tiers do for a crew working in California

A Cal/OSHA inspector standing on a California right of way is not going to write 1910.269. Under 29 CFR 1952.7, "The California State plan received initial approval on May 1, 1973" and "covers all private-sector employers and employees, with several notable exceptions, as well as State and local government employers and employees, within the State." The citation will be Title 8, and the approach distance will come from Table 1 of 8 CCR 2950 or from section 2951, which are not these tables and do not produce these numbers.

The federal tiers still govern the reader in three concrete ways.

First, as the floor. 29 U.S.C. 667(c)(2) conditions approval of a state plan on its standards taken together with their enforcement. The test is whether they "are or will be at least as effective in providing safe and healthful employment and places of employment as the standards promulgated under section 655 of this title which relate to the same issues."

Where a California provision is silent on something 1910.269 addresses, the federal text is the benchmark against which the silence gets measured, and arguing that it does not apply is an argument about the state plan, not about the span.

Second, as the rule for construction work. 29 CFR 1926.950(a)(3)(i) sends line-clearance tree trimming for the line operator to 1910.269 even when the job is construction, so the federal scheme does not fork by project type the way most of Part 1926 does. There is one federal standard for this work and one set of tiers in it, whether the crew is clearing for a rebuild or on a maintenance cycle.

Third, as the vocabulary of the contract. Utility line clearance specifications, mutual aid agreements and multi-state crew rosters are written in federal terms, because a company working Oregon and Nevada alongside California cannot maintain three vocabularies. A bid document that asks for "269-qualified" personnel is asking a specific question with a specific answer: five competencies under (a)(2)(ii), not three under (a)(2)(iii). Answering it with a line clearance card answers a different question.

The sorting that happens at 7:00 on a Tuesday morning under a 12 kV feeder is the same sorting either way. Who goes up, how close they may come, whether a second trained person has to be inside voice range, and whether anyone on the crew is permitted to touch an energized part at all.

The federal standard answers those four questions in a scope paragraph, a training list and two tables. Knowing which of the three tiers each name on the crew sheet belongs to, before the bucket goes up, is the whole of it.

Further reading

• Qualified line clearance tree trimmer versus qualified tree worker: The two California credentials that answer the same question this standard answers federally, and answer it differently.

• Table 1 of 8 CCR 2950: the minimum approach distance, and who owes it: The distance a Cal/OSHA inspector actually writes against on a California right of way.

• Incidental line clearance and what an arborist may not assume: What happens to the tiers when the job is not being done on behalf of the utility.

Frequently asked questions

What are the three qualification levels under OSHA 1910.269?

OSHA's line-clearance tree trimming eTool names them as unqualified employees, 269-qualified employees, and line-clearance tree trimmers. Only the last two appear in the standard's own text, at 29 CFR 1910.269(a)(1)(i)(E)(1) and (E)(2). The first tier is defined by exclusion: a person doing tree work near a line who is neither a qualified employee nor a line-clearance tree trimmer falls outside 1910.269 and is governed by Subpart S, principally 1910.333(c)(3). The split between the other two is made by paragraph (r)(1), whose second sentence reads 'This paragraph does not apply to qualified employees.'

How far back does an unqualified worker have to stay from a power line?

Ten feet for voltages to ground of 50 kV or below, and 10 feet plus 4 inches for every 10 kV over 50 kV above that, under 29 CFR 1910.333(c)(3)(i)(A). The distance applies both to the person in an elevated position and to the longest conductive object that person could contact, and 1910.333(c)(3)(i)(B) applies the same figures to anyone on the ground bringing a conductive object toward the line.

What is the minimum approach distance for a line-clearance tree trimmer at 12 kV?

Table R-6 of 1910.269 prints 0.65 meters (2.14 feet) for phase-to-ground exposure and 0.68 meters (2.24 feet) for phase-to-phase exposure in the 5.1 to 15.0 kV band, at worksites 900 meters (3,000 feet) above sea level or lower. Separately, 1910.269(r)(1)(ii)(A) requires a second line-clearance tree trimmer within unassisted voice communication from 10 feet in, on anything energized at more than 750 volts, so nearly eight feet of that approach is covered by a two-person rule before the trimmer reaches the table distance.

Does the federal standard set a number of months of training for a line-clearance tree trimmer?

No. 1910.269 defines a line-clearance tree trimmer as an employee who, through related training or on-the-job experience or both, is familiar with the special techniques and hazards involved in line-clearance tree trimming. There is no period, no hour count, no certifying body and no expiry in that definition. What the standard does impose is a competency list at 1910.269(a)(2)(iii) and a proficiency requirement at (a)(2)(viii). California is where the clock comes from: 8 CCR 2700 sets 18 months for its own credential.

Does 1910.269 apply in California?

Not as the enforced standard. Under 29 CFR 1952.7 the California State plan received initial approval on May 1, 1973 and covers all private-sector employers with several notable exceptions, along with state and local government, so a Cal/OSHA inspector writes Title 8. 1910.269 still matters in three ways: 29 U.S.C. 667(c)(2) requires the state standards to be at least as effective as the federal ones on the same issues, 29 CFR 1926.950(a)(3)(i) makes 1910.269 the rule for line-clearance tree trimming even when the job is construction work, and utility contracts and multi-state crews routinely carry the federal vocabulary.