This document contains definitions of welding terms and specifications across 4 modules. Module 1 defines common welding terms and specifications including the ANSI/AWS welding standard, welding inspector certifications, and structural welding codes. Module 2 defines safety terms related to welding like exposure limits, personal protective equipment, and hazards. Module 3 continues with additional welding definitions. Module 4 provides definitions for joint geometry terms including weld types, sequences, and dimensions.

1. Module 1.
AWS A 3.0- The ANSI/AWS Standard welding terms and definitions. This defines welding related
terms with standard definitions.
AWS B 5.11-98 The AWS specification for the Qualification of radiographic Interpreters.
AWS D 1.1- The AWS Structural Welding Code- Steel. Used worldwide for construction of building
and structures.
AWS D 1.5- The AWS Bridge Welding Code used in the U.S. for construction of bridges.
AWS D 15.1 – the AWS Railroad Welding specification – Cars and Locomotives. This specification
covers welding of railroad cars and locomotives.
CAWI -- Certified Associate Welding Inspector.
CWI – Certified Welding Inspector.
KASH – An Acronym for Knowledge, Attitude, Skills, and Habits. The basic tool of a welding
inspector.
QC – 1 The ANSI/ AWS Standard for AWS Certification of Welding Inspectors. Defines the
requirements and program for the AWS to certify welding inspector.
MODULE 2
ACIGH – The American Conference of Governmental and Industrial Hygienists. This group is
concerned with the proper; Safe levels of Exposure the Hazardous materials.
Adiabatic Recompression – The term given to the temperature rise that can occur when some gasses
at high pressure are released suddenly.
ANSI/ ASC Z 49.1 – Safety in Welding Cutting and Allied processes, A document outlining safe
practices for welding and cutting operations.
ANSI Z 87.1 – Practice for Occupational and Educational eye and face protection.
Asphyxiation – Loss of consciousness as a result of too little oxygen or too much of carbon dioxide
in the blood.
Filter Lens – In welding a shade lens usually glass, that protects the eyes from radiation from the
welding arc and other heat source. Welding lenses are numbered, with the higher numbers offering
the greatest protection. See Lens shade selection. Table 2.2 page 2-21.
Fire watch – A person whose primary responsibility is to observe the work operation for the
possibility of fires, and to alert the workers if a fire occurs.
Fume Plume – In welding a smoke like cloud containing minute solid particles arising directly from
molten metal.
Lock Tag and Try – The phrase noting the physical locking out of equipment. Tagging it for
identification, and trying the equipment to make sure it is not operable prior to beginning any repair
work.
MSDS---Material Safety Data Sheet.
OSHA—Occupational Safety and Health Act. This federal law outlines the requirement for safety in
the workplace.
Pascal (Pa)—The unit for pressure, or tensile strength. The U.S. customary equivalent is psi.
1 psi.= 6895 Pa.
Pinch Point—Any equipment geometry that can lead to pinching parts of the body, especially the
hands or feet, while working on the equipment.
Safety Glasses—Spectacles with hardened and minimum thickness lenses that protect the eyes from
flying object. Improved eye protection occurs when side shields are attached to the safety glasses.

2. Standby—In welding a person trained and designated to stand by and watch for safety hazards, and
to call for help if needed. Most often used for vessel entry safety.
TLV—Threshold Limit Value. The permissible level of exposure limits for hazardous materials.
MODULE -- 4
Actual Throat – The shortest distance between the weld root and the face of a fillet weld.
Back Weld-- A weld made at the back of a single groove welded joint after the completion of the
groove weld.
Backing – A material or device placed against the back side of the joint or at both sides of a weld in
elect slag and electro gas welding, to support and retain molten weld metal. The material may be
partially fused or remain un fused during welding and may be either metal or non metal.
Backing Weld—Backing in the form of a weld, made before the primary weld.
Back step Sequence—A longitudinal sequence in which weld passes are made in the direction
opposite to the progression of welding.
Bevel Angle—The angle between the bevel of a joint member and a plane perpendicular to the
surface of the member. This dimension equals one- half of the groove or included angle when the
edges of both members are prepared at the same angle. When only one member is prepared at an
angle, the dimension is still indicated in the same position on the welding symbol for groove angle,
but equals the total degree of preparation for the groove.
Bevel Groove Weld—A type of groove weld in which the mating members of the joint have one
single bevel or double bevel edge and one square edge preparation.
Block Sequence —A combined longitudinal and cross sectional sequence for a continuous multiple
pass weld in separated increments are completely or partially welded before intervening increments
are welded.
Boxing – The continuation of a fillet weld around a corner of a member as an extension of the
principle weld.
Buildup – Surfacing variation in which surfacing material is deposited to achieve the required
dimensions.
Buttering – A surfacing variation that deposits surfacing material on one or more surfaces to provide
metallurgically compatible weld metal for the subsequent completion of weld.
Butting member – A joint member that is prevented, by other member from movement in one
direction perpendicular to its thickness dimension.
Cascade sequence – A combined longitudinal and cross sectional sequence in which weld passes are
made in overlapping layers.
Chain intermittent fillet weld. An intermittent weld on both sides of a joint in which the weld
increments (lengths) on one side are approximately opposite those on other side.
Cladding A surfacing variation that deposits or applies surfacing material usually to improve
corrosion or heat resistance.
Convexity The maximum distance from the face of a convex fillet perpendicular to a line joining
the weld toes.
Effective Throat – The maximum distance minus any convexity between the weld root and the face
of a fillet weld.
Face Reinforcement – Weld reinforcement on the side of the joint from which welding was done.
Faying Surface— The mating surface of a member that is in contact with or in close proximity to
another member to which it is to be joined.

3. Fillet weld leg —The distance from the joint root to the toe of the fillet weld.
Flange weld—A non standard term for a weld in a flange joint. In the case of a flange weld symbol
representation, the symbol identifies a flanged joint rather than a specific type of weld.