Acceptors (see also Receivers)

Personnel authorised with responsibility for accepting/receiving permits to work

Air toxicant

Where the balance of the natural air composition is disturbed through the addition of another substance

Authorised Personnel

Personnel authorised responsible for specific aspects of a permit to work system

CABA

Compressed Air Breathing Apparatus

CCTV

Closed Circuit Television

CS

Confined Space

DOL

Department of Labor (USA)

Egress

Exit

FAHBA

Fresh Air Hosed Breathing Apparatus

Flash point

The lowest temperature at which vapours given off a liquid will ignite

FMEA

Failure Modes and Effects Analysis

HAZOP

Hazards and Operability Studies

HSA

Health & Safety Authority (Ireland)

HSA

Health & Safety Agency (NI)

HSC

Health & Safety Commission, UK

HSE

Health & Safety Executive (UK)

IDLH

Immediately Dangerous to Life or health

in.

Inch

Inert Gas

Non-combustible gas

Ingress

Entry

Issuers

Personnel authorised with responsibility for issuing permits to work

LEL

Lower Explosive Level

LFL

Lower Flammable Limit

LTEL

Long-term exposure limit. Usually an 8 hour TWA reference period

m

Metre

MEL

Maximum Exposure Level. The maximum concentration of airborne substances. They must never be exceeded.

Metabolic heat

Heat generated within the body

MIP

Major Incident Plan

mm

Millimetre

MSDS

Material Safety Data Sheet

NI

Northern Ireland

NIOSH

National Institute for Occupational Safety and Health (US Government body)

NMB

National Medical Body

NSSB

NVQ

National Vocational Qualification, UK competence based qualifications

OEL

Occupational Exposure Limit

OES

Occupational Exposure Standard. The concentration of airborne substances at which there is no evidence that repeated exposure will cause any ill health effects. It should not be exceeded or if it is steps must be taken to reduce the exposure.

OH&S

Organisational Health & Safety

OHSA

Occupational Safety & Health Administration (USA)

PEL

Permissible Exposure Limit. The exposure standard set by the NSSB. It may be a TWA or a maximum concentration level.

PPE

Personal Protective Equipment

ppm

Parts per million. A unit of measurement for the concentration of a gas or vapour in the atmosphere.

psi

Pounds per square inch

PTW

Permit to Work

RAL

Recommended Alert Levels. Maximum working times in high ambient temperatures for workers not acclimatised.

RCD

Residual Current Device. These devices detect earth faults and cut off the supply to the circuit.

RCE

Risk Control Estimator

Receivers (see also Acceptors)

Personnel authorised with responsibility for accepting/receiving permits to work

REL

Recommended Exposure Levels. Maximum working times in high ambient temperatures for acclimatised workers

RPE

Respiratory Protective Equipment

S.R.

Statutory Rules, relates to UK statutes

S.R.& O.

Statutory Rules and Orders, relates to UK statutes

SCBA

Self Contained Breathing Apparatus

SI

Statutory Instrument, relates to UK statutes

STEL

Short-term exposure limit. Often applied to a substance where it essential to restrict exposure to the minimum reference period, usually 10 or 15 minutes.

SWP

Safe Working Procedure

TLV

Threshold Limit Value. An exposure limit below which most people can work for 8 hours without any ill health effects.

TWA

Time Weighted Average. The airborne concentration of a substance to which a person is exposed taken as an average over the total exposure time.

UK

United Kingdom

USA

United States of America

VPP

Voluntary Protection Program

WBGT

Wet Bulb Globe Thermometer