December’s Seven Letters of Interpretation from OSHA

Why OSHA’s December Letters Matter

In December 2025, the Occupational Safety and Health Administration announced seven letters of interpretation addressing workplace safety and health requirements. Technically, these were not all written in December; OSHA’s announcement gathered attention around letters issued earlier in 2025, from January through June. But the December release mattered because it packaged them as a clear signal: OSHA wants employers, workers, safety managers, and compliance teams to understand how the agency reads its rules in real workplace situations.

A letter of interpretation is not a new regulation. It does not rewrite the Occupational Safety and Health Act, and it does not magically turn a confusing standard into a beach read. Instead, it explains how OSHA applies existing standards to specific facts. That distinction is important. Employers cannot treat these letters as loopholes, but they can use them as practical guidance when building safety programs, training supervisors, documenting hazard assessments, or deciding whether a compliance approach is defensible.

The seven letters covered permit-required confined spaces, COVID-19 recordkeeping, powered industrial truck training, electronic OSHA recordkeeping forms, engineering controls for benzene and 1,3-butadiene, audiometric testing for workers with cochlear implants, and stair angle and tread depth requirements. That is a surprisingly wide menu: a little construction, a little general industry, a little health care, a little chemical exposure, and just enough paperwork to remind everyone that safety compliance loves a good form.

What Is an OSHA Letter of Interpretation?

OSHA letters of interpretation are official written explanations of how the agency understands and applies specific OSHA standards. They usually respond to a question from an employer, attorney, trade group, safety professional, or another stakeholder. The letters often begin with a narrow factual scenario, then explain whether a particular OSHA standard requires, allows, or prohibits a certain practice.

For SEO purposes, the phrase “OSHA letters of interpretation” sounds a bit stiff, but for compliance purposes, it is pure gold. These letters help employers navigate gray areas where the regulation is broad, technology has changed, or a workplace setup does not fit neatly into the examples most people learned in training class. They are especially useful for safety directors who have ever stared at a standard and thought, “That is clear as mud, but somehow with more acronyms.”

OSHA also makes clear that these letters do not create additional employer obligations. They explain existing requirements under statutes, standards, and regulations. In practice, that means an employer should use them as guidance, not as a substitute for reading the standard itself, reviewing state-plan requirements, and getting legal or safety advice when the facts are complicated.

The Bigger Context: DOL’s Opinion Letter Push

The December OSHA announcement fits into the Department of Labor’s broader 2025 emphasis on opinion letters and compliance assistance. The DOL announced a renewed opinion-letter program in June 2025, describing opinion letters as tools for giving workers and businesses clear, practical guidance on federal labor laws. OSHA’s version of that tool is the letter of interpretation.

For employers, the practical value is predictability. Safety compliance is not supposed to be a guessing game played with hard hats and fines. When OSHA explains how it interprets a standard, employers can update policies, training, forms, inspections, and job hazard analyses with more confidence. For workers, clearer interpretations can also mean safer procedures, better training, and fewer arguments over what the rules actually require.

Still, a letter of interpretation is not a universal permission slip. It applies to the facts presented. Change the facts, and the answer may change too. A forklift evaluation performed by livestream is not the same as classroom instruction delivered online. A stair tread with a nosing is not automatically compliant just because the tape measure looks friendly. Details matter. OSHA letters are built almost entirely out of details.

The Seven OSHA Interpretation Letters Explained

1. Permit-Required Confined Spaces and Water-Filled Pipes

The first letter addressed permit-required confined spaces in a large university utility system. The question was whether an employer must isolate and drain all flowable utility piping before workers enter a permit-required confined space, even when the piping passes through the space, does not terminate there, and the employer’s hazard assessment shows no reasonable probability of rupture or leakage.

OSHA’s answer focused on hazard evaluation. The permit-required confined space standard is performance-oriented, meaning employers must assess the specific hazards present. If piping contains water, steam, or another flowable material and the employer determines there is a potential for rupture, leakage, engulfment, burns, or another serious hazard, isolation is required. But if the employer’s evaluation shows the piping does not terminate in the space and no potential exists for rupture or leakage into the space, OSHA said isolation of that piping is not required.

The takeaway is not “never drain pipes.” The takeaway is “document a serious hazard assessment before deciding.” Employers should consider the age and condition of piping, inspection history, maintenance records, prior failures, proximity of the work to valves or flanges, and the volume or flow that could enter the space. A confined space entry permit should tell a clear story. If it reads like someone filled it out while sprinting to lunch, that is not ideal.

2. COVID-19 Recordkeeping and Reporting Under 29 CFR 1910.502

The second letter dealt with OSHA’s COVID-19 recordkeeping and reporting requirements under the health care emergency temporary standard. OSHA stated that it would not enforce certain COVID-19 log and reporting requirements under 29 CFR 1910.502 until further notice. However, the agency also made clear that it would continue to enforce applicable recordkeeping and reporting requirements under 29 CFR Part 1904.

This distinction matters. Employers should not assume that all COVID-related recordkeeping evaporated. If a case is work-related and otherwise recordable under OSHA’s general injury and illness recordkeeping rules, Part 1904 may still apply. Health care employers, safety officers, and HR teams should keep their recordkeeping systems current and avoid the tempting but dangerous phrase, “I thought we were done with that.”

3. Powered Industrial Truck Training and Livestreamed Evaluations

The third letter answered a very modern question: Can a qualified trainer evaluate a powered industrial truck operator virtually, using a livestream from a phone, tablet, or computer? OSHA’s answer was no for the practical evaluation. Under 29 CFR 1910.178, trainees may operate a powered industrial truck only under the direct supervision of a qualified person. OSHA interpreted direct supervision to mean that the qualified individual must be physically located where the practical training and evaluation occurs.

That does not mean technology has no role in forklift training. Classroom-style instruction can often include videos, online materials, or other digital tools. But the hands-on evaluation is different. A forklift is not a webinar with forks. The evaluator needs to observe the operator, workplace conditions, equipment, maneuvering, loads, pedestrians, and hazards in real time and in person.

4. Software-Generated OSHA Forms 300 and 300A

The fourth letter will make safety software vendors and recordkeeping managers lean forward. OSHA confirmed that software-generated documents may substitute for OSHA Forms 300 and 300A if they meet the requirements for equivalent forms. The forms must contain the same information, be as readable and understandable, and be completed using the same instructions as the OSHA forms they replace.

OSHA also emphasized that electronic records must be able to produce equivalent forms when needed. Government representatives, employees, former employees, and authorized representatives may have rights to access certain records. Employers can keep records digitally, but they must be able to provide usable copies when required. In short, “It is somewhere in the system” is not a recordkeeping strategy. It is a scavenger hunt.

Employers using safety management software should audit their OSHA 300 and 300A outputs. Do the fields match? Are summaries certified properly? Is the annual Form 300A, or equivalent, posted from February 1 through April 30 when required? Can the system export readable paper or electronic copies? If the answer is “probably,” that is a polite invitation to test it before an inspector does.

5. Engineering Controls Under the Benzene and 1,3-Butadiene Standards

The fifth letter addressed whether bellow valves, leak-proof valves, and double-seal valves qualify as engineering controls under OSHA’s benzene and 1,3-butadiene standards. OSHA said yes. The agency explained that these standards are performance-oriented and allow employers to use combinations of engineering controls and work practices suited to the facility, as long as employee exposures are reduced and maintained at or below permissible exposure limits.

OSHA also explained that even conventional valves may be considered engineering controls depending on facility conditions, process design, leakage potential, pressure, and exposure levels. The key point is not the label on the valve; it is whether the control actually controls exposure. Fancy hardware with poor maintenance is just expensive decoration.

Employers in chemical manufacturing, refining, laboratory operations, or similar industries should connect this letter to exposure monitoring, leak detection and repair, maintenance schedules, and compliance plans. Engineering controls are not one-and-done purchases. They require verification, inspection, and documentation.

6. Audiometric Testing for Workers With Cochlear Implants

The sixth letter addressed audiometric testing for a worker who uses a cochlear implant. OSHA explained that its occupational noise standard does not include a specific exception for workers with cochlear implants. The employer must still offer audiometric testing to employees covered by the hearing conservation requirements.

OSHA stated that the cochlear implant should be turned off before the audiometric test begins because leaving it on would prevent accurate measurement of natural hearing thresholds. The worker may use the device to receive test instructions, then turn it off for the actual test. OSHA also noted that licensed or certified audiologists, otolaryngologists, physicians, or other qualified professionals play important roles in reviewing audiograms, determining validity, identifying work-relatedness, and deciding whether referral is needed.

This letter is a useful reminder that safety programs must account for individual worker needs without abandoning the standard. Employers should coordinate with qualified medical professionals, protect confidentiality, and avoid making assumptions about hearing ability or test validity.

7. Stair Angle and Tread Depth Requirements

The seventh letter addressed whether stairs built after January 17, 2017, with an angle between 49 and 50 degrees and a stated tread depth of 9.5 inches could comply with OSHA’s stairway standard when the run was only 8 inches plus a nosing. OSHA said no.

OSHA explained that the minimum tread depth requirement is intended to provide adequate stepping space and protect employees from falls. Tread depth must be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at a right angle to the tread’s leading edge, excluding certain beveled or rounded surfaces that slope more than 20 degrees.

The lesson is simple: stair measurements are not vibes. Employers, contractors, facility managers, and maintenance teams should verify stair angle, riser height, tread depth, width, landings, and handrails before assuming a stairway is compliant. A nosing may help with foot placement, but it does not automatically rescue an undersized tread.

Compliance Themes Running Through All Seven Letters

Hazard Assessments Must Be Real, Not Ritual

The confined space letter shows OSHA’s continued reliance on site-specific hazard assessment. Employers cannot simply copy last year’s permit, swap the date, and call it compliance. They need to evaluate actual conditions, including equipment age, failure history, work location, energy sources, and potential exposure.

Technology Helps, But It Does Not Replace Judgment

The letters on livestreamed forklift evaluations and electronic recordkeeping forms both touch technology. OSHA is not anti-technology. Digital records can be acceptable, and online tools can support training. But technology must meet the standard. A livestream cannot provide the physical presence required for practical powered industrial truck evaluation. Software-generated forms must still be equivalent to OSHA’s required forms.

Performance-Based Standards Still Require Proof

Several letters involve performance-oriented standards. That gives employers flexibility, but flexibility is not the same as freedom from documentation. If an employer chooses a method because it fits the facility, it should be able to show why the method protects workers and satisfies the standard.

Medical and Disability-Related Issues Require Careful Handling

The cochlear implant letter shows the importance of balancing OSHA compliance with individualized medical realities. Employers should involve qualified professionals, protect worker privacy, and avoid one-size-fits-all assumptions.

What Employers Should Do Now

Employers do not need to panic over the December OSHA letters. Panic is rarely a compliance strategy, unless the strategy is to create more paperwork for everyone. Instead, safety teams should treat the letters as a useful checklist.

First, review whether any of the seven topics apply to your workplace. Campuses, manufacturing plants, hospitals, warehouses, chemical facilities, logistics operations, and construction-adjacent employers may all find something relevant. Second, compare existing policies with OSHA’s interpretation. Look at confined space permits, forklift training programs, recordkeeping software, chemical exposure controls, hearing conservation procedures, and stairway inspections.

Third, document decisions. If a confined space evaluation concludes that a pipe does not need to be drained, preserve the reasoning. If software generates equivalent OSHA forms, verify the fields, readability, certification, posting, and access process. If a powered industrial truck program uses digital modules, make sure the practical evaluation still happens in person. If workers with cochlear implants are included in a hearing conservation program, coordinate testing with qualified professionals.

Finally, remember OSHA State Plans. State-plan states must be at least as effective as federal OSHA, but they may have different or additional requirements. A federal interpretation letter is influential, but employers in state-plan jurisdictions should check local rules before treating the federal answer as the final word.

Practical Examples for Safety Teams

Example: A University Utility Vault

A university facilities team needs to enter a vault containing chilled water lines. Draining the system would disrupt dormitories and laboratories. The team should not simply skip draining because it is inconvenient. Instead, it should evaluate whether the piping terminates in the space, whether work will affect valves or flanges, whether the piping is in good condition, whether there is a history of leaks, and whether any release could engulf or burn entrants. If the documented evaluation shows no potential for rupture or leakage, OSHA’s letter supports the idea that isolation of that piping may not be required.

Example: A Warehouse Forklift Refresher

A warehouse wants to evaluate forklift operators by having them drive while a trainer watches through a video call. OSHA’s interpretation says that will not satisfy the direct supervision requirement for practical evaluation. The employer can still use digital materials for classroom instruction, but the practical evaluation needs an in-person qualified evaluator.

Example: A Digital Safety Platform

A company uses safety software that produces OSHA-style injury and illness logs. The software is acceptable only if the output is equivalent to required OSHA forms. The company should test whether the forms include the same information, follow the same instructions, remain readable, and can be provided to employees or OSHA representatives when required.

Experience-Based Insights: What These OSHA Letters Feel Like in the Real World

Anyone who has worked around safety compliance knows that OSHA interpretation letters are not casual reading. They are not the sort of thing people bring to a beach vacation unless the beach has a very strict permit-required-confined-space program. But in real workplaces, these letters can be surprisingly useful because they answer the questions that come up after the training video ends and the actual job begins.

One common experience for safety managers is the gap between written standards and messy facilities. A regulation may describe a requirement clearly, but the building was constructed in three eras, renovated by five contractors, and labeled by someone whose handwriting looked like a weather event. In that environment, the confined space letter is valuable because it reinforces a practical principle: evaluate the actual hazard. Do not blindly over-control and shut down half a campus if the hazard does not exist, but do not under-control just because draining a system is inconvenient. The right answer depends on documented facts.

Another familiar experience is the pressure to modernize everything. Training platforms, safety apps, electronic logs, cloud dashboards, and mobile inspections can make compliance more efficient. The December letters show that OSHA is willing to recognize modern tools, especially for recordkeeping. At the same time, the forklift training letter draws a bright line around practical evaluation. Watching someone operate heavy equipment through a screen may feel efficient, but OSHA expects the evaluator to be physically present. In practice, that means companies should separate digital convenience from tasks that require direct observation, physical presence, and immediate correction.

Recordkeeping is another place where experience matters. Many employers assume that if their software produces a clean-looking injury log, it must be compliant. But OSHA’s interpretation is more precise. Equivalent forms must contain the same information, be readable, follow the same instructions, and be accessible when required. A safety manager who has ever tried to export records during an audit knows the difference between “stored digitally” and “available in a useful format.” Those are not always the same thing.

The chemical exposure letter also reflects a real-world truth: equipment choices are rarely perfect. A facility may use bellow valves, double seals, conventional valves, ventilation, leak detection, monitoring, and work practices in combination. OSHA’s performance-based approach allows flexibility, but it expects proof that exposure is controlled. From an operational standpoint, that means maintenance and monitoring are just as important as purchasing. A premium valve that is never inspected can become a very expensive way to lose an argument.

The cochlear implant letter is especially important because it reminds employers that safety programs involve people, not just charts. Workers may have medical devices, disabilities, accommodations, or individual testing needs. A good hearing conservation program should not treat those situations as annoyances. It should involve qualified professionals, communicate respectfully, protect confidentiality, and still meet OSHA’s requirements.

Finally, the stairway letter is a classic facilities lesson: small measurements can create big risks. A stair that feels “close enough” may not meet OSHA’s tread depth requirement. In the field, this is where safety, maintenance, architecture, and operations need to talk to one another before a worker trips, falls, and everyone suddenly becomes an expert on nosing angles.

The broader experience-based lesson is that OSHA interpretation letters reward employers who slow down, verify facts, document reasoning, and train supervisors to ask better questions. They are not shortcuts. They are road signs. And in workplace safety, a good road sign is much better than discovering the cliff by committee.

Conclusion

December’s seven letters of interpretation from OSHA are more than a year-end compliance footnote. They show how the agency applies existing standards to modern workplace questions involving confined spaces, COVID-19 recordkeeping, forklift training, electronic forms, chemical exposure controls, hearing conservation, and stairway design.

The main message is practical: employers should not guess. They should assess hazards, document decisions, verify training methods, audit software-generated forms, maintain engineering controls, involve qualified medical professionals, and measure physical workplace features accurately. Safety compliance may never be glamorous, but when done well, it is calm, defensible, and far less dramatic than an OSHA citation arriving like a holiday fruitcake nobody ordered.