OSHA letters of interpretation on tree care: the eight letters OSHA lists

This page reports what the official source says. It is not legal advice: ask the office named here. A letter of interpretation is OSHA's reading of a standard on the facts one person described. OSHA's own note on each letter says its interpretation letters explain requirements and how they apply to particular circumstances, but cannot create additional employer obligations, and that its guidance can change when rules change. The letters date from 1994 to 1999. OSHA's tree care page also lists its June 24, 2021 inspection guidance for tree care, and the guide on OSHA standards for tree work covers the standards themselves.

The eight letters

These are the letters in the "Additional Letters of Interpretation" list on OSHA's tree care standards page. The titles are OSHA's, with one spelling corrected.

Date	OSHA's title	Standard cited
September 23, 1999	Protection of ground-level workers from lowering of aerial lift bucket	1910.67, 1926.453
April 26, 1999	Clarification of 1910.269 as applied to line-clearance tree-trimming operations	1910.269(a), (r)
December 31, 1998	Acceptability of western style hard hats	1926.100, 1926.95
October 29, 1998	Apparel requirements for line-clearance tree-trimmers	1910.269
June 8, 1998	Fall protection anchorage points: guardrail systems and cranes	1926.502
June 4, 1996	Interpretation of the electric power generation, transmission, and distribution standard	1910.269
September 25, 1995	OSHA's new fall protection standards for construction will prohibit use of safety belts with side dee rings as part of a personal fall arrest system	1926.500 to 1926.503
July 18, 1994	Clarification of electric power generators, transmission and distribution standard	1910.269

September 23, 1999: a ground worker under a lowering bucket

A risk management firm described a hazard no specific standard covers: workers on the ground near an aerial lift truck being struck by the personnel bucket as it is lowered. It asked whether OSHA would cite an employer for the exposure, and whether an audible alarm that sounds while the bucket lowers would remove the risk of a citation.

The OSHA regional administrator answered that a General Duty Clause citation was possible if each element was present: a hazard that could cause serious injury, enough industry or employer knowledge of it, and an employer aware that workers were exposed. Because neither a standard nor the ANSI A92.2 consensus standard addresses the hazard, she wrote that the answer depends on the facts of each employer and site. On the alarm, the letter says it would not by itself be viewed as acceptable abatement, since OSHA knew of no evidence it would reduce the hazard. It gives reasons: a bucket operator can look over the side and see whether someone is below, workers get used to a constant sound, chain saws and chippers raise ambient noise, hearing protection blocks sound, and an alarm may lead operators to skip looking. It says the most effective protection is training and supervision so that operators do not move the bucket unless they can see it is safe.

April 26, 1999: which paragraphs of 1910.269 apply to line-clearance tree trimming

A regional administrator asked about a tree service planning work close to energized conductors. The Directorate of Compliance Programs answered that all of 1910.269 except paragraph (r)(1) applies to qualified employees, meaning those knowledgeable in the electrical equipment and its hazards. For line-clearance tree trimmers who are not qualified employees, it lists paragraphs (a)(2), (b), (c), (g), (k), (p) and (r), covering training, medical services and first aid, job briefing, protective equipment, material handling and mechanical equipment, plus the special line-clearance work practices.

The letter says training workers only in rubber gloves and sleeves would not satisfy the training requirements for work within the minimum approach distances. It says those employees must be trained as qualified employees, or be undergoing on-the-job training, have shown they can work safely at their level, and be under the direct supervision of a qualified employee. It also points to paragraph (r)(7) on ropes used by line-clearance tree trimmers and to an ASTM specification for polypropylene rope with special electrical properties.

December 31, 1998: western style hard hats

An Indiana OSHA office asked whether hard hats with brims meet 1926.100 on head protection, given worries that hot items could lodge in the brim or a struck brim could knock the hat off. The Directorate of Construction answered that a hard hat meeting ANSI Z89.1-1969 meets the falling and flying object requirement, and that the later 1986 edition is more rigorous. It says a brim being struck does not change that. For other head hazards the employer must ensure protection, and for burn hazards 1926.95 applies. The letter adds that products should not carry labels saying OSHA approved them, since OSHA does not endorse products.

October 29, 1998: apparel for line-clearance tree trimmers

A utility's compliance specialist noted that paragraph (l)(6)(iii) does not apply to trimmers who are not qualified employees and that paragraph (r) has no apparel rules, and asked what the apparel requirements are. The acting director answered that 1910.269(g)(1) sends protective equipment to Subpart I, that equipment which may include clothing must be provided, used and maintained as 1910.132 requires, and that it must be chosen to protect against the hazards found in the hazard assessment.

June 8, 1998: anchorage points on cranes

A crane company's safety manager asked about 1926.502(d)(23) and how to reach a crane runway from an aerial lift. The Directorate of Construction answered that the rule bars attaching personal fall arrest systems to guardrail systems or hoists except as other subparts allow, and that guardrails designed for it under (d)(15) are the exception. Where cranes lack suitable anchorages, employers are guided by 1926.502(a)(2), which has fall protection installed before work starts. The letter says planning should place proper anchorages before work begins instead of using alternatives that may not comply.

June 4, 1996: first aid and CPR for field crews

A utility asked whether 1910.269(b)(1) requires tree trimmers and line workers in the field to give first aid and CPR within four minutes, and to be proficient in tree and pole top rescue in that time. The Director answered that field crews need at least two trained employees and fixed sites enough trained people to respond within 4 minutes. The letter says the four minutes was not an absolute limit on responding to an accident. For non-fixed locations it lists three things used to judge compliance: whether exposed workers are within 4 minutes of a trained person, whether equipment and procedures exist to reach an injured worker on a pole, and whether assigned people have shown proficiency with the rescue equipment, even if that means going inside the minimum approach distance. A second question on tagout is about generating plants and is not about tree work.

September 25, 1995: side D-rings

A manufacturer of safety belts asked whether the new construction fall protection standards would bar belts with side D-rings as part of a personal fall arrest system. The Director of the Office of Construction and Maritime Compliance Assistance answered that side D-rings are acceptable for work positioning devices, such as those used by linemen, rebar workers or tree trimmers, but not for fall arrest. It says belts with side D-rings used for fall arrest do not comply and would not be grandfathered, and that most manufacturers said a belt turned ninety degrees, so the side ring sits at the center of the back, could be used for fall arrest. The letter also says the use of body belts for fall arrest is prohibited from January 1, 1998.

July 18, 1994: the arborists' trade association's eight questions

The attorney for the National Arborist Association asked OSHA to clarify eight points of 1910.269 as they affect tree trimming and offered wording for each. OSHA's answers:

Training records: it agreed the employment record can serve, if the certification is immediately available at the job site where the employee reports.
When to certify: certification is made immediately after the employee shows proficiency, and an interim certification may be needed before an employee climbs or works in trees without supervision.
First aid and CPR from a prior employer: it agreed, so long as the documents are valid and up to date.
First aid supplies: neither standard requires the consulting physician's approval to be in writing, though OSHA agreed it is a good idea.
Energy source controls: it agreed that instruction can be that all overhead wires are treated as energized unless the utility confirms deenergization.
Safety saddle: it agreed the body belt and strap rules do not apply to the safety saddle required by (r)(8).
Uninsulated saws near lines: it did not accept the proposed wording and pointed to the specified distances in the standard.
Palms: it accepted modified wording on the use of a lanyard and safety saddle in palms and similar trees.