Solvent and Rag Storage and Fire Control

Purpose

Keep the flammable half of a paint job under control from the moment it comes off the truck to the moment the waste leaves the site. Two mechanisms do nearly all the damage in this trade and they are different: solvent vapor, heavier than air, travels along a floor to a pilot light and burns back to the container, and oil-cured rags generate their own heat and ignite hours after everyone has gone home.

Scope

Storage, transport, transfer, ignition-source control and waste handling for flammable and combustible liquids and for oil-cured rags on residential and small commercial coatings work: solvent-borne primers and enamels, strippers, thinners, cleaning solvents, oil-based stains and the rags used with them.

It does not cover disposal routing for paint, washout water and leftover product (see the paint waste and washout disposal standard, which owns where the waste goes once this SOP has it in a closed container), sprayer flushing procedure (see the airless sprayer standard), or coating selection.

Roles and responsibilities

Procedure

1. Class every product on the truck by its own safety data sheet before the day starts. Read section 2 for the classification and section 9 for the flash point, and write the class beside each product on the day's material list. Acceptance: every solvent-bearing product on the list carries its flash point and class, with flammable liquids separated on the list from combustibles. Wrong, and the stop rule: a product with no SDS on file does not go on the truck, because the storage and ignition rules below are set by the number nobody looked up. Hazard: none at this step, it is a desk decision, and it is a step because the liquid is not what burns; vapor above the liquid is, and the flash point is the temperature at which there is enough of it.

2. Carry and store in listed safety cans, in the quantity the day needs. Transfer bulk solvent into listed safety cans with a self-closing lid and flame arrester, keep the truck to the day's work, and store the balance at the shop in a listed flammable liquids cabinet. Acceptance: every flammable liquid on the truck in a listed can, upright, latched and secured against sliding, with shop cabinet quantities inside the limits of 29 CFR 1910.106 where the work is general industry or 29 CFR 1926.152 where it is construction, and of NFPA 30 in the edition your authority having jurisdiction has adopted. Wrong, and the stop rule: thin original containers rolling loose in a van split at the seam, so a leaking or dented container is emptied into a safety can or left at the shop, never taped. Hazard: a closed van in sun runs well above ambient and vapor collects at floor level where a safety can's relief vents, so the van is ventilated before anyone leans in, and no solvent stays overnight in an occupied home.

3. Bond and ground before any transfer between containers. Clamp a bonding conductor bare metal to bare metal between the pouring and receiving containers before the lid comes off, and ground the receiving container where it is a drum. Acceptance: the bond visibly clamped to unpainted metal on both containers before the first pour, with the transfer outdoors or in the ventilated area named at step 4. Wrong, and the stop rule: no bond, no pour; a plastic pail cannot be bonded, so the transfer waits for metal rather than proceeding carefully. Hazard: flowing solvent generates static and the spark lands at the container mouth where vapor is richest, so the pour is slow, the containers stay in contact, and nobody transfers solvent in an unventilated space however well bonded.

4. Survey and kill the ignition sources before the first container opens. Walk the room and the space below it, shut off pilot lights and standing appliances including water heater, furnace and range, keep heaters, heat guns and heat lamps out of the space entirely, and keep motors, cords and vacuums outside the vapor zone. Acceptance: a written list of what was shut off, and no open flame or spark source in the space or on the level below it. Wrong, and the stop rule: an ignition source that cannot be shut off, such as a sealed-combustion appliance the crew may not touch, moves the operation to another room or changes the product to a waterborne one. Hazard: solvent vapor runs downhill along a floor and down a stair to a basement appliance, so the survey covers the level below the work, and where spraying is involved the spray-area electrical classification under NFPA 33, in the edition your authority having jurisdiction has adopted, governs what equipment may run there at all.

5. Put a Class B extinguisher in the work area and brief the response before work starts. Set an inspected extinguisher rated for flammable liquids inside the work area, not in the truck, and say out loud who calls and where everyone meets. Acceptance: a current inspection tag, sized and placed per NFPA 10 in the edition your authority having jurisdiction has adopted, within the work area and not behind the work. Wrong, and the stop rule: no extinguisher on site means no solvent work that day, which is a dispatch problem rather than a judgment call. Hazard: the response is everyone out and the fire department called first; a crew member fights only a fire still confined to its container, from the doorway with a clear exit behind them, and water never goes on a solvent pool fire because it floats the burning liquid and spreads it.

6. Put a listed oily-waste can in the room before the first oil-based product opens. Set a self-closing oily-waste can inside the work area, and put every rag, tack cloth, sanding pad and paper towel that touched an oil-based product into it the moment it leaves the hand. Acceptance: the can present and self-closing before the first can of alkyd, stain or oil primer opens, and no rag on a drop cloth, ladder shelf or windowsill at any point in the shift. Wrong, and the stop rule: a rag balled up and set down is the failure this step exists for, so a crew that finds one clears every rag in the room before continuing. Hazard: alkyds, oil stains and linseed products cure by oxidation, which releases heat, and a balled rag insulates that heat instead of shedding it until the pile reaches ignition hours later with nobody in the building. That is why the control is a container and not a habit.

7. Empty the can and take the temperature check every shift, before anyone leaves. At close, empty the oily-waste can to the route the waste standard names, or spread rags flat and individually outdoors on a non-combustible surface away from the structure and the vehicle until they are stiff. Acceptance: the can empty at close, and any waste container or rag pile read with an infrared thermometer no more than 10 F above ambient, a shop default worth tuning but not skipping. Wrong, and the stop rule: anything warmer than that gate is already reacting, so it goes outside immediately, away from the structure and the vehicle, is spread flat or drowned in water in a closed metal container, and the shop is told that night rather than the next morning. Hazard: the person carrying a warm container carries a possible ignition, so it goes out at arm's length, direct to open ground, and not through an occupied room or into a van.

8. Close the site out with nothing flammable left inside and everything restored. Confirm every container is latched, nothing solvent-bearing or rag-bearing stays in the customer's home, and every appliance on the step 4 list is relit and running. Acceptance: the step 4 list fully restored with each item checked off by name, zero solvent containers and zero rags in the building, containers upright and secured in the van. Wrong, and the stop rule: an appliance that will not relight is not left for the customer to sort out; the office and the customer are told that evening and a water heater or furnace that will not restart goes to the appropriate trade the same day. Hazard: this is the step that puts an ignition source back into a space that held vapor, so the space is ventilated first, the pilot is lit only after the room is clear of solvent odor, and the crew does the relight rather than the customer.

The record this produces

Per job: the classed material list from step 1, the step 4 shut-off list with restore checkmarks and times, the extinguisher tag date, the daily rag-can empty confirmation with its temperature reading and the ambient it was read against, any warm-container event with what was done and who was told, and the customer's written agreement where material was stored in their garage. The temperature readings are what an insurer asks for after a fire, and the shut-off list proves a water heater was relit by the crew rather than found off a week later.

One run of this procedure, filled in

Interior trim and doors in an occupied two-story, oil-based alkyd enamel over an oil primer, plus a small stripping operation at a stair rail. Two painters, three days. Step 1: enamel and primer both flammable per their sheets, the stripper the lowest flash point of the three, all three classed on the day list. Step 2: day quantities in listed safety cans, balance at the shop, cans latched and strapped in the van.

Step 3: one transfer of thinner into a metal pail at the stair, bonded clamp to bare metal on both containers, poured outside the door. Step 4: gas water heater and furnace in the basement directly below the stair, both pilots shut off and written on the list along with the kitchen range; the customer was told at the morning brief that hot water would be off from 9 a.m. Step 5: extinguisher tagged current, set at the stair landing rather than in the van.

Step 7 fails on day two. The oily-waste can was on the truck rather than in the room all morning, so rags accumulated on a drop cloth beside the door. At the 3 p.m. check the room read 72 F ambient and the rag pile read 96 F on the infrared thermometer. That is 96 minus 72, or 24 F above ambient, well past the 10 F gate the step's acceptance states, so the stop rule fired: the pile went straight out to open gravel away from the house and the van, was spread flat, and the shop was called that afternoon. Nothing ignited. The correction was written the same day, and on day three the can went into the room before the first lid came off, which is step 6 as written and was the actual defect.

Step 8 at close each day: containers latched, no rags and no solvent left in the house, the step 4 list restored item by item. On day one the furnace relit first try and the water heater took two attempts, both confirmed running by the lead before the crew left, and the range pilot went last, after the stair was ventilated for the time the stripper's sheet calls for.

References

• 29 CFR 1910.106 for flammable liquids in general industry and 29 CFR 1926.152 for construction, the fork applied at step 2.
• NFPA 30, Flammable and Combustible Liquids Code, and NFPA 33 for spray application, each in the edition your authority having jurisdiction has adopted, which reach you through the permit and through your insurer.
• NFPA 10 for portable fire extinguisher selection, placement and inspection, in the edition your authority having jurisdiction has adopted.
• Product safety data sheets, sections 2, 7 and 9, for classification, storage requirements and flash point; the label governs where it differs from anything here.
• See related: the paint waste and washout disposal standard, the airless sprayer setup and daily shutdown standard, the deck and fence staining job standard.