Maharashtra HSC NSQF Plumber General II flashcards

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

Confined space entry test order

Test the atmosphere for oxygen first, then flammable gas, then toxic gas. Entry is allowed only if oxygen is 19.5–23.5 percent and other readings are within limits.

Trench shoring depth rule

Any trench deeper than 1.5 m requires shoring, benching, or a trench box. Spoil is kept at least 0.6 m from the edge and a ladder must extend 1 m above the top.

Oxygen cylinder colour code

In India, oxygen cylinders are black with a white shoulder, acetylene cylinders are maroon, and LPG cylinders are red. Oil or grease must never contact oxygen fittings.

Leptospirosis risk in drainage

Rat urine in sewers and drains can carry leptospirosis bacteria. Plumbers must wear gloves and boots, cover cuts, and wash thoroughly before eating or smoking.

Pipe wrench size meaning

A pipe wrench is sized by its handle length, not the pipe it grips. A 350 mm wrench suits pipes up to about 40 mm nominal bore.

Reaming after pipe cutting

Cutting a pipe leaves an internal burr that reduces flow area and traps debris. A pipe reamer or half-round file removes the burr before jointing.

Nominal bore versus outside diameter

Nominal bore is a size label, not an exact diameter. A 25 mm nominal bore GI pipe has an outside diameter of about 33.5 mm, so measure before choosing fittings.

Solvent cement joint procedure

Clean both surfaces, apply cement to socket and spigot, push fully with a quarter turn, hold for 30 seconds, and allow 24 hours before pressure testing.

BSP taper versus parallel thread

A BSP taper thread seals on the thread flanks using jointing compound. A BSP parallel thread seals on a gasket or O-ring face and cannot seal alone.

Water hammer arrestor function

A water hammer arrestor or air chamber near a quick-closing valve absorbs the pressure surge that causes banging and pipe vibration when flow stops suddenly.

Hydraulic pressure test rule

Fill the completed line, expel air, and apply 1.5 times the working pressure, with a minimum of 10 bar for domestic work. Hold for at least one hour and check for drop.

Pipe support spacing rule

Horizontal 15–20 mm pipe is supported about every 1 m, 25–50 mm pipe every 1.8–2.4 m, and 80–100 mm pipe every 3 m. Vertical stacks are clamped at each floor.

Direct versus indirect water supply

Direct supply feeds fixtures straight from the mains. Indirect supply fills a storage tank first and distributes by gravity, which suits areas with low or intermittent mains pressure.

Vent stack termination height

The vent pipe must rise full bore above the roof, at least 300 mm above the roof surface and about 900 mm from any window or air intake.

Trap seal depth requirement

A trap must hold a water seal of 25 to 75 mm. Too shallow allows sewer gas through; too deep is hard to maintain and may siphon.

Drainage gradient for soil pipe

A 100 mm soil pipe is laid at about 1 in 40 to 1 in 60. A 150 mm pipe uses 1 in 60 to 1 in 100. Excessive slope lets water outrun solids.

Floor trap outlet size

A floor trap, also called a nahani trap, usually has a 50 mm outlet and a removable grating set flush with the finished floor, with the trap accessible below.

Bottle trap application

A bottle trap is used where the waste pipe cannot be trapped below the fixture. It provides a 25–75 mm water seal and is fitted above the floor.

Geyser safety fittings

An electric geyser needs a pressure relief valve on the hot outlet, a non-return valve on the cold inlet, and proper earthing. The thermostat is normally set at 60–65 °C.

Float valve in storage tank

A float valve controls tank filling by closing when the water level rises. The inlet is set about 25 mm above the overflow level so the overflow stays visible.

Isometric plumbing drawing

An isometric drawing shows the pipe run in three dimensions with pipe sizes and fitting symbols along each line. It is used for installation and material take-off.

Drawing scale calculation

On a 1:50 drawing, 1 mm on paper equals 50 mm on site. Measure the drawn length in mm and multiply by 50 to get the real length.

Wastage allowance in estimate

A material take-off adds 5 to 10 percent of pipe and fitting quantities for cutting wastage, breakage, and offcuts before the total cost is calculated.

Bill of quantities units

Pipe is measured in metres, fittings and fixtures in numbers, waterproofing in square metres, and excavation or concrete in cubic metres.

Smoke test purpose

A smoke test is used on completed drainage systems where water cannot fill the pipe. Smoke is forced in and leaks are traced by escaping smoke.

Dripping tap repair

Shut off the supply, dismantle the tap, and replace the worn washer on a compression tap or the ceramic cartridge on a quarter-turn tap.

Drain auger use

A drain auger or snake clears a blockage by feeding a flexible cable into the drain and rotating it through the obstruction. A CCTV survey locates collapsed pipes.

Water hammer repair options

Fit an air chamber or arrestor near the valve, or install a pressure-reducing valve if supply pressure exceeds about 3.5 bar. Secure loose pipe clamps too.

Estimate versus quotation

An estimate is an internal calculation of likely cost. A quotation is a formal written offer to the client with rates, scope, taxes, and validity.

GST invoice requirements

A GST invoice must show the GSTIN, a unique invoice number, date, client details, description with HSN or SAC code, taxable value, and tax rate.

Udyam MSME registration

Udyam registration is the online MSME registration for a small plumbing enterprise. It supports access to bank credit and government scheme benefits.

Defect liability period

A defect liability period, commonly 12 months after completion, obliges the plumber to repair defects in workmanship or materials at no extra cost.