1910.147 — energy control, all of it, not just electrical.
The energy control standard covers every hazardous energy source in the building — electrical, mechanical, hydraulic, pneumatic, thermal, chemical. In a data center that means it reaches the chiller plant, the fuel system and the fire suppression as much as it reaches the switchgear.
1910.147 does not apply to exposure to electrical hazards from work on, near, or with conductors or equipment in electric utilization installations — that is governed by 1910.333. In practice you run one energy control program covering all energy types, with an electrical annex built on NFPA 70E Article 120.
§ What it covers here
- Mechanical plant — chillers, pumps, cooling towers, air handlers. Rotating equipment, stored pressure, thermal energy.
- Fuel systems — day tanks, transfer pumps, fuel polishing.
- Fire suppression — clean agent cylinders are stored energy, and an accidental discharge during maintenance is a real event.
- Compressed air and hydraulics — dampers, actuators, dock levellers.
- Electrical — through the 1910.333 route rather than directly.
§ The written program
Energy control procedures — documented, and specific enough to be followed.
Employee training — authorized, affected and other employees, each at the right depth.
Periodic inspection — at least annually, by an authorized employee other than the one using the procedure.
Lockout devices — durable, standardized, substantial, identifiable, and used exclusively for energy control.
Group lockout, shift change and contractor coordination provisions.
§ Equipment-specific procedures
A documented procedure is required for each machine or equipment, unless the narrow exception applies — a single energy source that can be readily identified and isolated, with no potential for stored energy, and a lockout device that achieves complete de-energization.
In a data center almost nothing meets the single-source exception. A chiller has electrical, refrigerant pressure, water pressure and thermal energy. A PDU has two feeds and a transformer energized from both sides. A UPS has input, output, static bypass, maintenance bypass and a battery.
That means documented, equipment-specific procedures for essentially everything — and those procedures are on a one-year audit cycle under both 1910.147(c)(6) and NFPA 70E 110.3(L)(4).
Procedures written at commissioning against the original configuration, never updated through two capacity expansions. The annual inspection exists precisely to catch this, and it is the inspection most often performed as a paperwork exercise rather than by watching someone actually use the procedure.
§ The annual inspection
- Performed at least annually, on each energy control procedure.
- Performed by an authorized employee other than the one(s) using the procedure being inspected.
- Must include a review between the inspector and each authorized employee of that employee's responsibilities under the procedure.
- Must be certified — identifying the machine, the date, the employees included, and the person performing the inspection.
The intent is to observe the procedure in use and correct deviations. A signature on a checklist without an observation does not satisfy the standard, and it does not catch the outdated-procedure problem that annual inspection exists to find.
§ Running one program that satisfies both
| OSHA 1910.147 | NFPA 70E Art. 120 | |
|---|---|---|
| Energy types | All hazardous energy | Electrical |
| Written program | Required | Required — 120.2(A), explicit in 2027 |
| Verification | Verify isolation | Test before touch, instrument verified before and after; additional testing where voltage alone is inconclusive — 120.5(B)(6) |
| Audit cycle | Annual inspection of procedures | Program 3 yr, procedures 1 yr |
| Tagout devices | Addressed | Addressed — 2027 deleted the nylon cable tie material spec |
The practical structure: one energy control program document satisfying 1910.147 for all energy types, with an electrical annex that meets Article 120 — including the ESWC verification steps OSHA does not spell out. Full crosswalk →
LOTO that holds up under both
The 16-hour class builds the electrical annex against your actual topology — dual feeds, UPS bypass, battery.
See the 16-hour class Bring it onsite