Red Seal Painter & Decorator cheat sheet

WHMIS 2018 (GHS-aligned) uses 9 pictograms; supplier labels require product identifier, hazard statements, and precautionary statements; Safety Data Sheets have 16 sections and Sections 1-8 must be available in the workplace.

Lead paint is presumed in buildings built before 1960 in Canada; test with a chemical test kit or XRF before disturbing. Ontario's lead regulation sets a 50 µg/m³ TWA exposure limit; Alberta uses 0.05 mg/m³.

Silica: crystalline silica from sanding or abrasive blasting causes silicosis. Wet methods, HEPA vacuum attachment, and a half-mask respirator with P100 filters are minimum controls; sandblasting with silica sand is banned in most jurisdictions.

Isocyanate hardeners (polyurethane, 2K epoxy) cause occupational asthma; use supplied-air or an air-purifying respirator with organic vapour cartridge plus particulate prefilter, and never rely on odour as a warning.

VOC limits: Canada's Volatile Organic Compound (Paints and Coatings) Regulations set categories by coating type; many provinces also regulate solvent content. Waterborne acrylics typically under 250 g/L; solvent-borne alkyds often 350-500 g/L.

Flash point vs. flammable range: solvents with flash points below 37.8 °C (100 °F) are Class I. Ground and bond metal containers when decanting; static discharge ignites vapours in low-ventilation areas.

Confined-space entry requires a permit, atmospheric testing (oxygen 19.5-23%, LEL under 10%, H2S and CO below limits), an attendant, and a retrieval system; spray painting a tank interior is a permit-required entry.

Waste streams: leftover paint is hazardous waste unless accepted by a provincial paint-recycling program (e.g., Product Care); solvent rags must go in a self-closing metal can because linseed and alkyd oil rags self-heat and can ignite.

Fall protection is required at 3 m in most Canadian jurisdictions (2.4 m in some); a personal fall-arrest system includes full body harness, lanyard with shock absorber, and anchor rated at 22 kN (5,000 lb).

Coverage formula: area (m²) = length × height; subtract openings larger than 0.9 m². Litres needed = area (m²) ÷ spread rate (m²/L) × number of coats; add 10% for porous or textured surfaces.

Spread rate from label: theoretical spread (m²/L) × (1 - loss factor). Typical loss: 5% smooth interior, 10-15% exterior stucco, 15-20% rough sawn wood.

MIL thickness check: dry film thickness (DFT) = wet film thickness (WFT) × volume solids %. Measure WFT with a wet-film gauge immediately after application.

Gloss and sheen are measured at 60° (and 85° for low sheen); higher gloss means higher number. A 60° reading of 70+ is high gloss; 5-10 is flat.

Surface profile: new concrete must cure 28 days before coating; test moisture with a calcium chloride or plastic sheet test. Coatings need a profile of at least 50-75 µm (2-3 mil) on steel; SSPC-SP 6 (commercial blast) is common.

Wood moisture content should be 12-15% before painting; check with a pin meter. Knots in softwood need shellac or stain-blocking primer to prevent resin bleed.

Adhesion tests: cross-cut (ASTM D3359) for films under 125 µm; pull-off (ASTM D4541) for thicker systems. A pass requires less than 5% coating removal in the crosshatch area.

Galvanized steel needs a test for zinc salts (copper sulfate test) and a wash with solvent or an etch primer; new zinc surfaces are too smooth for direct topcoat adhesion.

Estimating labour: production rates are typically 8-15 m²/h for brush/roller interior walls, 4-8 m²/h for exterior trim. Multiply by a 1.3-1.5 factor for cut-in and detail work.

Brush types by task: natural bristle (China bristle) for solvent-borne paints and varnishes; synthetic (nylon/polyester) for waterborne. Natural bristle softens and swells in water.

Nap length: 6-8 mm for smooth surfaces and enamels, 10-13 mm for walls, 18-25 mm for rough masonry and stucco. Shorter nap gives a smoother finish.

Airless sprayer tip size: the three-digit number (e.g., 517) means 0.017 in orifice and 5 in fan width at 30 cm. Rule: 1 mil per 100 psi of pressure for a given tip.

HVLP sprayers atomize at low pressure (under 10 psi at the cap) and achieve high transfer efficiency (65-85%); conventional air spray is 25-40%.

Airless pressure is set just above the level needed to atomize; too high pressure causes overspray, tip wear, and bounce-back. Replace tips when fan pattern tails or the flow rate drops.

Roller covers: use a roller frame with a cage that fits the cover; load the roller by rolling in the tray, not dipping. A 230 mm (9 in) roller is standard for walls.

Solvent storage: flammable liquids cabinets must be labelled, vented if required by local code, and hold no more than the permit limit (often 45 L per cabinet in Canada).

HEPA vacuums for lead and silica dust must be rated for the hazard; a shop vac without HEPA spreads fine particles. Use a dust extractor with a M-class or HEPA filter.

Binder determines performance: alkyd (oil-modified) for adhesion and gloss on exterior wood; acrylic latex for flexibility, UV resistance, and low VOC; epoxy for chemical resistance on concrete and metal; polyurethane for UV-stable topcoats over epoxy.

Primer selection: zinc-rich primer for steel (sacrificial protection), zinc phosphate for ferrous metal, alkali-resistant primer for fresh concrete and masonry, stain-blocking shellac for knots and water stains.

Recoat windows: alkyds need 16-24 h; epoxies have a maximum recoat time (often 24-72 h) before sanding is required. Exceeding the window causes intercoat adhesion failure.

Colour systems: the Munsell system describes colour by hue, value, and chroma. Paint stores use tinting systems (e.g., Benjamin Moore Gennex, Sherwin-Williams ColorSource) where base choice depends on tint strength.

Tint strength: deep-tint bases have low titanium dioxide; adding too much colourant to a light base causes poor hiding and film defects. Use the correct base for the colour.

Metamerism: two colours match under one light source but not another because their spectral curves differ. Always approve colour under the specified lighting (D65 daylight or 3000K).

Sheen and colour: higher gloss intensifies colour and highlights surface defects; flat hides imperfections but is harder to clean. Exterior sheens resist dirt and UV better.

Epoxy and polyurethane mixing: mix by volume at the specified ratio, induction time (often 15-30 min) before use, and pot life (30 min to 8 h). Off-ratio mixing leaves a tacky film.

Drywall finishing levels: Level 4 (three coats, ready for flat paint), Level 5 (skim coat or primer skim, required for gloss and critical lighting). Level 3 is not suitable for gloss.

Joint compound vs. spackle: use setting-type compound for deep fills, drying-type for taping and finishing. Sand between coats with 120-150 grit; use a bright light to check for ridges.

Primer on new drywall: use a PVA or drywall primer to equalize absorption; unprimed drywall causes flashing and lap marks with topcoat.

Cut-in lines: brush a 50-75 mm band along ceilings and trim before rolling; roll into the wet cut-in within 10-15 minutes to avoid lap marks.

Ceiling and wall sequence: paint ceilings first, then walls, then trim; work from the top down. Mask trim with painter's tape rated for the cure time of the coating.

Enamel over latex: sand the latex to dull it, clean with a degreaser, and use a bonding primer; direct alkyd over latex can cause wrinkling if the latex is not fully cured.

Bathroom and kitchen coatings: use a semi-gloss or satin acrylic with mildewcide; allow 28 days cure before washing. Moisture-resistant alkyds yellow in low light.

Trim and doors: remove hardware or tape it; sand with 150-180 grit, prime bare wood, and apply two thin coats. Sand between coats with 220-320 grit for a smooth film.

Exterior wood: prime all six sides of trim and siding; back-priming prevents moisture wicking and paint failure at joints. Use an alkyd or acrylic primer compatible with the topcoat.

Stucco and masonry: new stucco cures 28 days; use an alkali-resistant masonry primer and an elastomeric or acrylic topcoat. Fill cracks with an elastomeric patching compound.

Metal: ferrous metal needs a rust-inhibitive primer (zinc phosphate or zinc-rich); galvanized steel needs a wash primer or etch primer. Aluminum needs a chromate-free conversion coating or etch primer.

Temperature and humidity: most exterior coatings apply between 10 °C and 30 °C and at relative humidity below 85%; surface temperature must be at least 3 °C above dew point to prevent amine blush and poor adhesion.

Exterior sheens: satin and semi-gloss resist dirt and mildew better than flat; flat exterior paints chalk and fade faster. Use a mildew-resistant coating in shaded, damp areas.

Caulking: use paintable acrylic latex caulk for most exterior joints; polyurethane for high-movement joints. Tool the bead and paint within the recoat window.

Deck finishes: transparent stains show wood grain but need reapplication every 1-2 years; semi-transparent and solid stains last longer. New pressure-treated wood must weather 3-6 months before coating.

Wind and sun: paint the shaded side first; direct sun causes the surface to dry too fast, leading to lap marks and blistering. Avoid painting in wind above 25 km/h.

Faux finishes: rag rolling, sponging, and colour washing use glaze over a base coat. Glaze extends open time; work in small sections and blend edges while wet.

Venetian plaster: lime-based plaster applied in thin layers and burnished with a stainless trowel; the finish hardens by carbonation. Seal with wax or a penetrating sealer.

Wallcovering paste: clear, wheat-based, or vinyl-to-vinyl. Use a vinyl-to-vinyl adhesive for vinyl over vinyl; clay-based paste for heavy or porous papers.

Wallcovering estimation: roll width 52 cm (20.5 in) and length 10 m (33 ft) are standard. Usable width after trimming is about 50 cm; allow 10-15% waste for pattern matching.

Pattern repeat: straight match aligns every repeat; drop match offsets by half a repeat; random match has no alignment. Calculate drops as roll length ÷ (wall height + repeat).

Wallcovering removal: score the surface, apply a removal solution, and strip from the top down. Vinyl-coated papers need scoring; strippable papers peel dry.

Metallic and pearlescent finishes: apply over a smooth, sealed base; brush marks show through. Use a spray or a high-quality synthetic brush and maintain a wet edge.

Wood graining and marbling: use a glaze over a base coat, then a badger softener or flogger to blend. Seal with a clear topcoat compatible with the glaze.

Area of a triangle: A = ½ × base × height. Area of a circle: A = πr². Circumference: C = 2πr. Volume of a cylinder: V = πr²h.

Paint quantity: litres = (area ÷ spread rate) × coats. For a room, wall area = perimeter × height - openings; ceiling area = length × width.

Wallcovering drops: drops per roll = floor(roll length ÷ (wall height + pattern repeat)). Total rolls = ceiling(total drops ÷ drops per roll).

Linear measure conversions: 1 m = 3.281 ft; 1 in = 25.4 mm; 1 gal (US) = 3.785 L; 1 gal (Imperial) = 4.546 L. Confirm which gallon the product label uses.

Estimating labour: labour hours = area ÷ production rate. Add 15-20% for setup, masking, and cleanup. Material cost = quantity × unit price × (1 + waste factor).

Work order documentation: record substrate, surface prep, primer and topcoat product names, batch numbers, DFT readings, temperature, humidity, and dew point.

Change orders must be written and signed before extra work proceeds; verbal approvals are not enforceable. Include scope, price, and schedule impact.

Colour and product documentation: record the tinting system, base, colourant formula, and sheen. Keep a spray-out or draw-down sample for warranty claims.