Setyr worked example — EC-1 E-Coat Dip Tank — Rectifier and Tank Entry Isolation Not approved for use. Version 1 · 2026-09-25
Worked example only — your site must author, review and approve its own
procedure under 29 CFR 1910.147(c)(4). setyr.com/procedures
EC-1 E-Coat Dip Tank — Rectifier and Tank Entry Isolation
Automotive paint
Anode replacement and tank entry on an electrocoat dip line. Covers the DC rectifier bus, the overhead conveyor carrying bodies over the tank, circulation and heat exchange, and the ventilation that must stay live in a solvent atmosphere.
This is a worked example, not a procedure you can adopt. It describes equipment that does not exist, with illustrative tag numbers.
29 CFR 1910.147(c)(4) requires the employer to develop, document and
utilise energy control procedures specific to their own machines, and (c)(6)
requires the employer to inspect those procedures periodically. Neither duty
can be delegated to a vendor or discharged by this document.
Isolation points
| # | Tag (illustrative) | Type | Disposition | What it does and why | Dwell |
|---|---|---|---|---|---|
| 10 | EC-1-RECT-AC | Breaker | Isolate & lock | Rectifier AC supply breaker, 480V feeding the e-coat DC rectifier. Caution: Isolating AC does not discharge the DC bus or the tank itself. Open, lock, prove dead on the AC side. | — |
| 20 | EC-1-RECT-DC | Disconnect | Isolate & lock | Rectifier DC output bus to the anode cells, 350V DC at high current. Caution: The bath is a conductor. A DC bus that has not been proved dead makes the whole tank live to anyone reaching into it. Open the DC bus disconnect, allow the bus to discharge, then prove dead at the anode busbar. | 300s |
| 30 | EC-1-ANODE | Disconnect | Isolate & lock | Anode cell isolation links at each cell along the tank. Caution: Cells retain charge individually. Proving the bus dead does not prove each cell dead. Open each cell link and lock the bank. Prove dead cell by cell, not just at the bus. | — |
| 40 | EC-1-CONV | Disconnect | Isolate & lock | Overhead power-and-free conveyor drive carrying bodies over the tank. Caution: A body indexing over an open tank with crew inside is the failure this point prevents. Open, lock, and prove dead at the drive. | — |
| 50 | EC-1-CONV-STOP | Block | Apply & verify | Mechanical carrier stops set either side of the tank on the conveyor rail. Caution: The conveyor is on a grade. Isolating the drive does not stop a carrier already rolling. Set stops both sides and confirm engaged. Must be ENGAGED. | — |
| 60 | EC-1-CIRC | Disconnect | Isolate & lock | Bath circulation pumps and the eductor loop. Caution: Circulation keeps solids suspended. It also creates flow that will pull a person against the eductor intake. Open and lock both circulation pump disconnects. | — |
| 70 | EC-1-UF | Valve | Isolate & lock | Ultrafiltration skid feed and permeate return valves. Caution: The UF skid returns permeate to the tank under pressure from a separate room. Close and lock both valves. | — |
| 80 | EC-1-HX | Valve | Isolate & lock | Bath heat exchanger hot water supply and return. Caution: Bath temperature is a burn and heat-stress hazard. Cooling takes time that crews compress under line pressure. Close and lock both valves, then allow the bath to cool below the entry temperature and confirm at two points. | 900s |
| 90 | EC-1-DI | Valve | Isolate & lock | Deionised water rinse header over the tank. Caution: Rinse headers fire on a timer tied to the conveyor, not to the tank. Close and lock the header valve. | — |
| 100 | EC-1-EXH | Breaker | KEEP ENERGISED | Tank exhaust ventilation over the bath. Caution: Solvent vapour above an e-coat bath is both a health hazard and a flammable atmosphere. Do NOT isolate. Confirm exhaust flow is above the low-flow setpoint before entry. | — |
| 110 | EC-1-LEL | Breaker | KEEP ENERGISED | Flammable atmosphere monitoring at the tank rim and on entrants. Caution: Entry into a tank that held solvent is permit-required regardless of how empty it looks. Do NOT isolate. Confirm LEL monitoring is in service. | — |
| 120 | EC-1-FIRE | Valve | KEEP ENERGISED | Tank deluge and foam suppression over the dip tank. Caution: Hot work near a solvent tank with suppression isolated is how the tank becomes a fire. Do NOT isolate. Confirm the suppression valve is open and sealed. | — |
What your site must supply
- Your own asset and isolation-point tag numbers. The tags shown are illustrative and refer to equipment that does not exist.
- The actual location of every disconnect, valve and vent on your equipment.
- Measured stored-energy magnitudes and the dwell time required to dissipate them.
- Your verification method for each point, and who is authorised to perform it.
- Any additional energy sources present on your equipment and absent here.
Authorship and validation
This example was authored by Setyr for domain validation. It is not derived from any customer's controlled documents. It illustrates the elements 29 CFR 1910.147(c)(4)(ii) requires a procedure to contain — it does not certify compliance, which is a property of an employer's programme rather than of any document.