Pet Urine Decontamination Standard

Purpose

Urine is not a stain, it is a volume that went through the carpet and spread sideways in the cushion and along the subfloor. The visible mark is the smallest part of it. A shop that prices and treats the visible mark books a job it cannot win: the topical pass looks perfect on the day, the salts left in the cushion pull moisture back out of the air the first humid week, and the customer calls to say the smell is worse than before you came, which is true, because you wet it.

This procedure maps the contamination before quoting it, sizes the treatment to the depth found, and puts the limit in writing where the customer signs it.

Scope

Covers detection, mapping, depth assessment, scoping, sub-surface treatment and extraction, cushion and subfloor decisions, and the dry re-check, on residential wall-to-wall carpet and stair runners.

Does not cover whole-room deodorization once the source is gone, or general spot chemistry; each has its own SOP. Structural drying after a water loss is a restoration procedure. Rugs go to the in-plant rug SOP, because a rug can be flushed and dried in a way an installed carpet cannot.

Roles and responsibilities

Procedure

1. Set the biological controls before the lamp comes out. Nitrile gloves on, eye protection for any step that flushes or sprays, no eating, drinking or phone handling with gloved hands, and hand washing before you touch anything of the customer's. Acceptance: gloves on, a waste bag staged, hand-hygiene supplies within reach. Wrong looks like a tech eating lunch in the van in the same gloves; urine and feces carry the ingestion route as well as the contact route, so gloves come off before the truck door handle, not after. Hazard: contaminated cushion and soaked backing hold liquid that squeezes out under a knee, so use a barrier rather than kneeling directly, and cover any break in the skin before the shift, not when you notice it.

2. Map every deposit with a lamp in a darkened room, and mark it. Close blinds, kill lights, and sweep a UV lamp at a low angle across the floor, marking each fluorescing area at its outer edge with chips or tape. Acceptance: every deposit has a marked surface footprint and a measured size in inches, on a room sketch. Wrong looks like reading fluorescence as proof: optical brighteners in a previous cleaner's detergent, some adhesives and some lint also glow, so confirm each mark with a second signal, either a moisture meter reading or the odor at pile level. Hazard: work under UV with the lamp pointed at the floor and not into anyone's eyes, keep the exposure short, and do not darken a room with a customer or a child walking in it, because a dark room with hoses across it is a fall.

3. Determine the depth of every marked deposit, because depth sets the whole scope. Take a moisture meter reading at the pile, then at the cushion through the carpet where the meter allows, then lift a corner at the nearest edge to look at the underside of the cushion and the subfloor. Acceptance: every deposit classified as surface only, cushion involved, or subfloor involved, with the evidence recorded. Wrong looks like a scope written off surface footprints, which always under-reads: the deposit at the cushion is materially wider than the mark on the face, and how much wider is measured on the job rather than assumed from a multiplier. Hazard: lifting a corner means tack strip, whose angled nails go through a finger to the bone, so lift with a knee kicker or pliers at the carpet face, keep hands out of the gripper channel, and re-seat any corner you lift before you move on, or note it as open with a barrier over it.

4. Write the scope, name the limit, and get the signature before anything gets wet. The scope names each deposit, its class, the treatment proposed, and what will not be resolved. Where subfloor is involved, the honest sentence is that odor comes back unless the cushion is replaced and the subfloor is sealed. Acceptance: a signed scope sheet listing every deposit from step 2, with the declined items named. Wrong looks like a verbal "we will do what we can"; if the customer declines a subfloor repair, that deposit gets no wet treatment at all, because adding solution to a contaminated subfloor you cannot access or seal reactivates the salts and drives them deeper, and it gets a dry counteractant plus a written note instead. Hazard: none at this step, it is a conversation at the kitchen table, and it is held with the machine off so the customer hears the limit.

5. Treat to the depth found, at the label's own rate and dwell. Saturate or inject enough solution to reach the contamination depth recorded at step 3, using an enzyme product where the label supports urine and giving it the moisture and dwell the enzyme needs. Acceptance: solution volume applied per deposit recorded, and the pile still damp at the end of the label dwell. Wrong looks like a light mist over a cushion-involved deposit, which treats nothing; if the product label conflicts with this SOP on dilution or dwell, the label governs and this step yields to it. Hazard: alkaline chemistry meeting urine salts releases ammonia, which is an inhalation route no glove addresses, so ventilate the room first, keep occupants and pets out through the dwell, never combine an enzyme with an oxidizer or a chlorinated product in the same treatment, and if anyone starts coughing or their eyes water, stop, get them outside, ventilate, and follow the label's first aid.

6. Extract sub-surface, then flush, and record what came back. Use a weighted sub-surface tool over each deposit, then flush with clear water and extract again until recovery runs clear. Acceptance: applied volume and recovered volume both written down per deposit, and the recovery visibly clear on the last pass. Wrong looks like a topical wand pass standing in for sub-surface extraction, which leaves the cushion loaded; if recovery is still colored after two flushes, stop flushing, because you are adding water you cannot get back, and move that deposit to the cushion replacement conversation. Hazard: the recovery tank now holds biological waste, so it is dumped to sanitary sewer per the shop's disposal rule and never onto a lawn, a driveway or a storm drain, and the tank and tool get cleaned and disinfected before the next house.

7. Where cushion replacement is in scope, cut, replace, seal and put it all back. Detach only the section needed, cut out the contaminated cushion against a straight edge, seal the subfloor per the sealer's label, fit new cushion, then re-stretch the carpet onto the tack strip. Acceptance: no loose edge anywhere on the re-stretched section, and the sealer cured per its label before cushion goes down. Wrong looks like carpet re-laid without stretching, which leaves a ripple that becomes a trip hazard and a wear line; if the carpet has lost its stretch or the backing is delaminating, stop and refer to an installer rather than forcing it. Hazard: two things here cut and one gasses. The knife works away from the body on a fresh blade, because a dull blade skids; carpet under stretch snaps back at the kicker, so keep hands clear of the gripper line; and solvent-borne sealers bring vapor and flammability, so ventilate, remove every ignition source including a pilot light in the same room, and where the label calls for respiratory protection that is a program under 29 CFR 1910.134, so if nobody on site is in one, the sealing does not happen today.

8. Dry it, re-check it dry, and book the odor verdict for later. Air movement on every treated deposit, then re-check with the moisture meter and the lamp once the area reads dry. Acceptance: treated deposits within a couple of points of the moisture reading on uncontaminated carpet in the same room, and no fluorescence remaining at a treated mark. Wrong looks like calling the job on the day, when odor is masked by moisture and the customer smells it back on day three; the odor verdict is taken at the dry re-check, so book it before you leave and tell the customer why. Hazard: air movers put cords across a floor a pet will run over, so run them along the wall line, tell the household which rooms have machines in them, and keep animals out of those rooms until the equipment is collected.

The record this produces

The room sketch with every deposit numbered, its surface size in inches, its depth class and the evidence for that class; the signed scope sheet with declined items; product, dilution and dwell per deposit; volume applied and recovered per deposit; any cushion and subfloor work with the sealer used; the dry re-check readings; and the odor verdict with its date.

Applied against recovered is the field that matters. It tells the next tech how much liquid stayed in the assembly, and it is the honest basis for the drying plan and for the conversation if the smell comes back.

Worked pass: three deposits, one that never gets wet

Bedroom with a cat, booked as a standard clean with a urine add-on. Step 2 maps three fluorescing deposits and confirms each with a second signal: A at 8 in across beside the closet, B at 6 in across under the window, C at 14 in across in the corner behind the door, all three confirmed by both meter and pile-level odor.

Step 3 classifies them. A reads elevated at pile and cushion with a clean subfloor at the lifted corner: cushion involved. B reads elevated at the pile only: surface only. C reads elevated at pile and cushion, and the lifted corner shows dark staining on the underside of the cushion and a matching stain in the subfloor plywood: subfloor involved.

Step 4 writes the scope. A gets sub-surface treatment and extraction, B gets topical treatment, and C is quoted with cushion replacement and subfloor sealing. The customer declines that repair. The stop rule fires: C gets no wet treatment, takes a dry counteractant only, and the scope sheet records in writing that its odor will return. The customer signs it.

Step 5 treats A and B at label dilution and dwell, window open, cat shut in another room. Step 6 sub-surface extracts A, flushes, and extracts again until recovery runs clear on the second flush; B takes a topical extraction. Volumes: 2.5 gal applied across A and B, 2.2 gal recovered, so 0.3 gal, which is 0.3 divided by 2.5, or 12 percent of what went down, stayed in the assembly and sets the drying plan.

Step 7 does not run, because the only deposit needing cushion work was declined at step 4. No knife, no sealer, no re-stretch.

Step 8 puts two air movers on A and B along the wall line. At the dry re-check, A and B read within two points of clean carpet in the same room and neither fluoresces. C still fluoresces, as the scope sheet said it would.

Self-check against the sections above: the three deposits mapped at step 2 are the same three carried through steps 3, 4 and 8; the wet-treatment total, 2.5 gal, covers only the two deposits the scope approved, and C never receives solution anywhere in this run; and 2.5 minus 2.2 leaves 0.3 gal, the figure the 12 percent is taken from.

References

• The label and safety data sheet for the enzyme, counteractant and any subfloor sealer used; label directions are legally binding in the chemical trades and govern dilution, dwell and required PPE
• 29 CFR 1910.134, which makes respiratory protection a written program with medical evaluation and fit testing rather than a purchase, and which gates the sealing step
• Local sewer authority rules for disposal of recovered biological waste, which vary by jurisdiction
• See related: carpetcleaning-pet-enzyme-treatment-protocol, carpetcleaning-pet-odor-deep-treatment, carpetcleaning-deodorization-service-standard, carpetcleaning-spot-and-stain-triage-standard