IICRC RCT flashcards

34 cards. Read the term and the definition here. The deck at the top of this page is optional.

Asymmetric knot

Persian or Senneh knot tied around one warp with an open loop on the other. It allows finer curvilinear design and is common on city and tribal Persian rugs.

Symmetric knot

Turkish or Ghiordes knot tied around two adjacent warps and pulled tight. It looks like two knot heads on the back and is typical of Turkish and Caucasian weaving.

Kilim construction

A slit-tapestry flatweave with weft-faced color blocks and no pile. Color changes leave small slits, and the rug has no pile height to protect during cleaning.

KPSI

Knots per square inch, calculated by multiplying warp knots per inch by weft knots per inch. Higher KPSI means finer yarn, denser weave, and slower drying.

Silk wet strength

Silk is a protein filament that loses roughly 20 percent of its strength when wet. Avoid agitation and heavy pressure on wet silk pile to prevent abrasion and distortion.

Viscose art silk

Regenerated cellulose fiber used to imitate silk. It has low wet strength, distorts easily, browns with slow drying, and shrinks, so clean with minimal moisture.

Pile direction

The direction pile fibers lean, usually toward one end of the rug. Brush and vacuum with the lay, because working against it raises nap and changes light reflection.

Colorfastness test

Apply the intended cleaning solution to a hidden area on each dye lot, blot with a white towel for 10 minutes, and check for dye transfer before cleaning.

Dry rot check

Lift a corner and flex the foundation. Crumbling or cracking indicates dry rot, which flags the rug as no-wet-clean and requires restoration referral before any cleaning.

Pre-existing stain record

Mark every existing stain on a diagram and photograph it under raking light before cleaning. Undisclosed stains are the most common source of damage claims.

Risk disclosure

A written list of known risks for the fiber and construction, such as bleeding, shrinkage, or browning, signed by the client before cleaning begins.

Turnaround planning

Hand-knotted rugs typically need three to seven days of controlled drying plus finishing. Schedule pickup and delivery around that window and confirm it in writing.

Expectation setting

Cleaning removes soil and improves appearance but does not guarantee removal of every stain, dye bleed, or odor. State this in the work order before starting.

Tannin stain chemistry

Coffee, tea, wine, and fruit stains are tannins that respond to acid-side spotting. Test the dye first, apply briefly, and rinse to neutral to avoid color loss.

Protein stain chemistry

Blood, milk, and egg stains respond to neutral to mildly acidic chemistry. Avoid heat and strong alkali, which set the protein and make removal harder.

Urine pH shift

Fresh urine is acidic, but bacterial action raises pH toward alkaline and produces ammonia and salts. Test pH and match the treatment chemistry to the reading.

Oxidizing agents

Hydrogen peroxide and sodium percarbonate brighten stains by oxidation. They can strip dye from silk, wool, and colored pile, so test every dye lot first.

Dry soil removal

Beating or vacuuming the back and face before any wet step. Grit left in the pile abrades fibers during agitation and dulls the rug over time.

Hand wash method

Full immersion in a controlled bath with mild detergent, soft brushing, thorough rinse, and controlled drying. It is the gentlest deep clean for hand-knotted wool.

Hot water extraction risk

High pressure and heat raise the risk of shrinkage, dye bleeding, and browning on wool. Use low pressure, moderate heat, and fast dry strokes.

Rotary shampoo limits

A surface method that leaves residue and works against delicate pile. It is unsuitable for silk, antique, or hand-knotted rugs that need gentle, low-moisture care.

Silk rug cleaning

No wet immersion. Use low-moisture solvent or dry methods, blot spills, and dry quickly to prevent watermarks, dye migration, and pile distortion.

Antique rug care

Clean only what is needed, because over-cleaning removes abrash and patina. Document every step, use gentle chemistry, and refer structural repair to a specialist.

Navajo weaving care

Handspun wool with natural dyes. Avoid strong alkali and high heat, test dyes for bleed, and dry flat to prevent warp shift and design distortion.

Tufted rug risk

Latex and secondary backing can delaminate with heat and excess water. Keep moisture low, avoid high heat, and dry fast to protect the backing.

Dye bleed prevention

Keep pH near neutral, limit dwell time, control water temperature, and dry quickly with air movement. These four controls reduce dye migration during wet cleaning.

Natural dye instability

Madder, indigo, and cochineal dyes on antique rugs are often less stable than synthetic dyes. Use cool water and short dwell, and test each color before cleaning.

Bleed response

Stop, blot, and flush with cool water. Do not apply heat or alkali. Call a dye-correction specialist and document the event with photos and times.

Drying window

Rugs should dry within 24 to 48 hours. Slow drying causes browning, mildew, delamination, and odor, especially on cotton foundations and viscose pile.

Airflow drying

Fans and dehumidifiers remove moisture faster than heat and are safer for dyes and fibers. Dry flat or on a supported rack, never hanging a wet hand-knotted rug.

Pile grooming

Brush the pile in the direction of its lay and comb the fringe straight. Grooming against the lay raises nap and produces a dull, uneven appearance.

Raking light inspection

Inspect the rug under low-angle light from both ends. Raking light reveals ripples, waviness, shrinkage, and shadow stains that flat lighting hides.

Safety Data Sheet

A document listing chemical hazards, handling, and first aid for each product. Read it before use, and keep solvents and oxidizers away from heat and sunlight.

Job documentation

Signed work order, dated photos, test results, product names and dilutions, drying records, and delivery receipt. Complete records support quality control and damage claims.