Haryana BSEH Secondary NSQF Plumbing flashcards

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

Confined space oxygen limit

Before entering a manhole or septic tank, test the atmosphere; oxygen below 19.5 percent by volume means entry is prohibited and forced ventilation plus a permit is required.

Trench shoring depth

Excavated trench sides deeper than about 1.5 metres must be shored, and excavated soil is stacked at least 0.6 metres away from the trench edge.

Class C fire extinguisher

Fires involving flammable gases are Class C and are extinguished with dry powder; electrical fires are fought with carbon dioxide, never with water or foam.

Pipe wrench jaw direction

The jaw teeth of a pipe wrench must face the direction of rotation so that the pull is taken toward the handle, giving a firm grip without slipping.

Hacksaw blade pitch

An 18 teeth per inch blade suits thick metal and pipe, 24 is general purpose, and 32 suits thin-walled tube and sheet where at least three teeth contact the work.

Pipe cutter operation

A pipe cutter scores and severs metal pipe; tighten the adjusting knob about a quarter turn per revolution, apply cutting oil, and ream the burr afterwards.

CPVC pipe use

Chlorinated polyvinyl chloride pipe carries hot water up to about 90 degrees Celsius and is joined with solvent cement, unlike UPVC which is mainly for cold water and drainage.

Galvanised iron pipe

Mild steel pipe coated with zinc by hot-dip galvanising, used for cold water supply and joined by threaded sockets and fittings; the zinc coating resists corrosion.

Check valve function

A check valve allows flow in one direction only and prevents backflow; a gate valve isolates flow, a globe valve throttles, and a ball valve gives quarter-turn isolation.

Nominal bore meaning

Nominal bore is the approximate internal diameter used to designate pipe size; a 25 mm nominal bore pipe has an outside diameter of about 33.4 mm.

Eccentric reducer placement

An eccentric reducer is offset to one side and is fitted in horizontal runs with the flat side up so that air pockets and condensate traps are avoided.

Union versus coupling

A union has three parts and allows a line to be disconnected without cutting, while a coupling is a simple sleeve joining two pipes of the same size.

File cut types

A single cut file has parallel teeth for finishing and sharpening, while a double cut file has crossing teeth for rapid metal removal; a bastard file is coarser than second cut.

Spanner selection rule

The spanner must fit the nut flats fully; use an open-end spanner for two-point access, a ring spanner for full grip, and pull toward the fixed jaw.

Fitting take-out

Take-out is the distance a pipe inserts into a fitting; cut length equals centre-to-centre length minus the sum of the take-outs at both ends.

Long radius elbow take-out

For a 90 degree long radius elbow, the take-out equals 1.5 times the nominal pipe diameter; for a short radius elbow it equals 1.0 times the nominal diameter.

PTFE tape winding direction

PTFE tape is wound clockwise around the male thread in the direction of tightening, about three turns, leaving the first thread bare so the joint starts cleanly.

Solvent cement joint cure

For a PVC solvent cement joint, clean and prime both surfaces, apply cement, insert with a quarter turn, hold about 30 seconds, and cure fully before pressure testing.

Compression joint tightening

Slide the nut and olive onto the tube, insert the tube fully, and tighten the nut hand tight plus about one and a quarter turns with a spanner without overtightening the olive.

Overhead tank minimum head

The overhead tank must give a minimum head of about 2 to 3 metres above the highest fixture so that adequate pressure reaches the top floor.

Fixture unit method

Each fixture is assigned loading units, about 3 for a water closet and about 1 for a wash basin, and the total selects the supply pipe size from a sizing table.

Water supply hydrostatic test

A new supply line is tested at about 1.5 times working pressure, with a minimum of 10 bar, for at least one hour with no drop on the gauge.

Wash basin rim height

A wash basin rim is fixed about 780 to 800 millimetres above finished floor level, with a 32 or 40 millimetre waste outlet and an accessible basin trap.

Floor trap water seal

A floor or gully trap retains a water seal of at least 50 millimetres to stop sewer gas entering the building and is placed at the lowest point of a wet floor.

Soil pipe versus waste pipe

A soil pipe carries human waste from water closets, while a waste pipe carries sullage from sinks and basins; a vent pipe equalises pressure in the system.

Self-cleansing velocity

Self-cleansing velocity is the minimum flow speed that keeps solids moving in a drain, about 0.6 metres per second, while the maximum permissible is about 3 metres per second.

Drainage gradient for 100 mm pipe

A 100 millimetre soil pipe is laid at a fall of about 1 in 60 to 1 in 80, while a 150 millimetre sewer uses about 1 in 100 to 1 in 150.

Dripping tap diagnosis

Water dripping from the spout means a worn washer or ceramic cartridge, while leakage at the spindle means worn gland packing or a perished O-ring.

WC overflow diagnosis

Water overflowing into the pan means the float valve is not shutting off, caused by a worn washer, a punctured float, or a misadjusted float arm.

Job card purpose

A job card records the work done at a site, while a material requisition requests stores, an invoice bills the customer, and a measurement sheet records quantities for payment.

Plumbing quotation contents

A quotation states the scope of work, material brand and grade, quantity, rate, total amount, time schedule, payment terms, and the validity period of the offer.