MSAPMOHS217A

Gas Test Atmospheres

Instructions for Use: To protect and maintain version control, this document is supplied as a PDF. All STP documentation is only to be used as intended and is

to be treated as “commercial in confidence” and covered by copyright, unless otherwise approved in

writing by STP.

To open in full screen, hold Ctrl and L.

Welcome to todays course:

To maximise the training benefit to yourself and others, please:  

Actively listen Turn your phone to silent Participate in discussions  Share you knowledge & experiences Respect others viewpoints Keep to the subject Comply with requirements Ask questions

Welcome

STP Site Induction

3

E.M.P.ExitsEvacuation AlarmMuster PointFire ExtinguishersFirst AidToiletsDuty of Care

S.D.S.P.P.E. Incidents / InjuriesLunch BarSmokingAmenitiesPersonal SecurityQuestions?????

Gas Test Atmospheres

MSAPMOHS217A

Gas Test Atmospheres

Version 1.2

Course Forms

Induction

Safety

Course Duration

IAW relevant AS’s

Site Requirements

Company Procedures

Breaks / Lunch

Mobile Phones

Training Frequency

L.L.N / Injuries

Questions?????

Administration

Competency Requirements

Theory Assessment (Open Book)

a. From the manual

Practical Assessmentb. Calibrate and test gas monitor, interpret and record atmospheric readings.

MSAPMOHS217A Gas Test Atmospheres

Objectives - to enable you to:

Identification of Confined Spaces

Conduct confined space risk assessment

Work according to Site procedures

Complete entry permit procedures

Use of appropriate PPE

Appreciation of rescue, first aid & fire fighting

Evidence of competency is gathered in two forms:

Knowledge is assessed with written and verbal answers. Skill is assessed throughout the course.

Occupational Safety and Health?

Each state and territory has occupational health and safety legislation in the form of Acts and Regulations (OSH, OHS, WHS) that are intended to ensure the health, safety and welfare of persons at work.

This course is to the Australian Standards, and also covers W.A. specifics.

Northern TerritoryWHS Act 2011

WHS Regulations 2011

Western AustraliaOSH Act 1984

OSH Regulation 1996

South AustraliaWHS Act 2012

WHS Regulation 2012

TasmaniaWHS Act 2012

WHS Regulation 2012

VictoriaOHS Act 2004

OHS Regulation 2007

ACTWHS Act 2011

WHS Regulation 2011

New South WalesWHS Act 2011

WHS Regulation 2011

QueenslandWHS Act 2011

WHS Regulation 2011

Acts and Regulations

WA OSH Regulations (1996):

• Regulation is linked to an Act and provides the specific detail on how that act is to be implemented.

• The Regulation sets out rules to prevent or control certain hazards which might cause injury or death in the workplace.

• Free download at http://www.safetyline.wa.gov.au

WA OSH Act (1984) :

An Act is a law passed by parliament to govern certain activities. • The aim of the Act is to prevent a person’s death, injury, or illness

being caused by a workplace.

Acts and Regulations

Australian Standards Australian Standards set out the safety requirements for

persons working in specific areas or who deal with specific equipment. These standards only become legally binding when they are incorporated into legislation.

Atmospheric Testing Requirements for confined spaces can be found in (AS) 2865:2009 Confined Spaces and more detailed information can be found in (AS) 61779.6:2003 Electrical Apparatus for the Detection and Measurement of Flammable Gases, particularly Table A which details specific gravity lower and upper explosive limits.

This Australian Standard outlines the minimum requirements for establishing a safe system for entry and conduct of tasks in or on a confined space

Australian Standards

AS 1319:1994 – Safety signs for the occupational environment

AS/NZS 1715:2009 – Selection, use and maintenance of respiratory protective equipment

AS/NZS 1716:2012 Respiratory protective devices

AS 1891 – Industrial Fall arrest systems and devices

AS/NZS 61779 Electrical apparatus for the detection and measurement of flammable gases

AS/NZS ISO 31000:2009 – Risk Management principles and guidelines

Confined Space Fatalities

95% are caused by an atmosphere that is not assessed

80% occur when performing a familiar task

64% occur even though the task could have been performed from outside

60% are unplanned rescue attempts

6 OUT OF 10 DEATHS ARE WOULD BE RESCUERS

Hazardous Gas Zones

Reference: AS/NZS 60079.10.1 2009

Zone “0” – Most Hazardous i.e. inside gas and sludge pipework. “An area in which an explosive gas atmosphere is present continuously, or is to be expected to be present for long periods, or for short periods which occur with high frequency.”

Zone “1” – Hazardous i.e. a space containing compressors, sediment traps etc. “An area in which an explosive gas atmosphere can be expected to occur periodically or occasionally during normal operation.”

Hazardous Gas Zones

Zone “2” – Potentially Hazardous i.e. within 1 meter of a flanged or screwed gas or sludge pipe joint. “An area in which an explosive gas atmosphere is not expected to occur in normal operation and if occurs is likely to be present only infrequently and for short periods.”

Non Hazardous Restricted Zone – “An Area not classified as Zone, 0, 1, or 2 but still subject to some restrictions.

A Competent Person Competent Person : A person who has,

through a combination of training, education and experience, acquired knowledge and skills enabling that person to perform a specified task correctly.

All Persons with tasks associated with a confined space SHALL be trained and assess as competent to conduct those tasks.

Refresher Training shall be conducted at appropriate intervals to maintain competency to conduct tasks associated with confined spaces

Responsibilities of a Business

A person who conducts a business has a legal and moral responsibility to ensure the health and safety of each employee and any other person is not affected by the conduct of that business

Must provide a safe place of work.

Must ensure a safe system of work.

Must provide PPE and training in its use.

Must provide information, training and

supervision.OSH Act 1984 Div 2 Section 19

Responsibilities of the WorkerNote: Please note that as an attendee, you are considered to be a worker and must therefore meet the corresponding requirements. If you have any concerns or questions, please see your Instructor.

A worker or anyone else at a workplace must:

Comply with instructions given for workplace health and safety.

Use PPE if provided.

Not interfere with or misuse safety equipment.

Not risk the health and safety of himself or herself, or any other person at the workplace.

 

Definition of a Confined Space (AS)

An enclosed or partially enclosed space that is not intended or designed primarily for human occupancy, within which there is a risk of one or more of the following:

a. An oxygen concentration outside the safe oxygen range.

b. A concentration of airborne contaminant that may cause impairment, loss of consciousness or asphyxiation.

c. A concentration of flammable airborne contaminant that may cause injury from fire or explosion.

d. Engulfment in a stored free-flowing solid or a rising level of liquid that may cause suffocation or drowning.

.

20

DefinitionEnclosed or partially enclosed can be of a design in which atmospheric contaminants could accumulate, such as heavier than air contaminants (Gases) in a pit, tank or sewage tunnel.

21

DefinitionNot intended or designed primarily …. In some confined spaces such as machinery pits and storage tanks persons may regularly enter for a variety of task including servicing and maintenance however the key point is that the design or intent of such areas is not primarily as a place of work but as a housing for equipment or storage of a product.

Note: A Confined Space isn't always a small space.

Definition

Oxygen outside the Safe Oxygen RangeThe safe oxygen range is 19.5% to 23.5% by volume, under normal atmospheric conditions. Oxygen values outside this range are considered unsafe.At atmospheric pressures significantly higher or lower than normal atmospheric pressure, expert advice should be sought.

Concentration of Airborne ContaminantA Contaminant is defined as: Any dust, fume, mist, vapour, biological matter, gas or other substance in liquid or solid form, the presence of which may be harmful to persons.If there is a risk that the space contains a level of contaminant that may cause impairment, loss of consciousness or asphyxiation; that space may be a confined space.

23

Hazards are not always obvious

?

Manholes Sewers

Tanks

Pits

Ship Holds

Ducts

Tunnels

Shafts Silos

Pipes ++++++

Confined spaces are not limited to the above.

Entry Permit

Entry Permit

• The entry permit outlines the procedures, guidelines and risk control measures to be followed for the confined space task.

• The entry permit may reference to other permits such as hot work, hazardous substances, or working at heights.

• Results of atmospheric testing should be recorded on the entry permit.

• The entry permit should be displayed in a prominent place adjacent to the entry, to facilitate signing and clearance

• The entry permit records the entry and exit times of personnel

Entry Permit

Atmospheric TestingAS 2865:2009 states that atmospheric testing or monitoring shall be conducted in a manner consistent with the hazards identified in the risk assessment of the confined space. 

Atmospheric Testing for Entry 

Atmospheric testing should include testing by scientific means for: 

• Oxygen concentration• Concentration of airborne contaminants• Concentration of flammable airborne contaminants

Oxygen Deficiency O2% in Air Symptoms

21 – 18% No noticeable effect

18 – 14% Increased respiration rate, faster heart beat, impaired attention, thinking and co-ordination

14 – 10% Very faulty judgement and muscular co-ordination. Muscular exertion causes rapid fatigue and possible permanent heart damage.

10 – 6% Nausea and vomiting, unable to perform vigorous movement or loss of all movement. Unconsciousness then death

6 – 2% Spasmodic breathing, convulsive movements, death

in minutes

< 2% Immediate unconsciousness

Atmospheric Monitoring Alarms

Gas Low/Warn High/Alarm Range

Oxygen 19.5% 23.5% 0 – 25%

LEL 5% 10% 0 – 100%

CO 30PPM 60PPM 0–500ppm

H2S 10PPM 20PPM

CL2 .5PPM 1PPM

High / Off / Over / OL / Note: Red denotes a latching alarm.

Airborne Contaminants

A contaminant is any dust, fume, mist, vapour, biological matter, gas or other substance in liquid or solid form, the presence of which may be harmful to persons. Contaminants include non-toxic or minimally toxic gases (known as asphyxiants) which dilute or displace oxygen in the atmosphere, which may result in death. Toxic contaminants are those which may be harmful to health and safety through being poisonous, corrosive, or carcinogenic. Many toxic contaminants have exposure limits. These are known as Workplace Exposure Standards.

Physiology of Respiratory ProtectionFresh Air = 78.09% Nitrogen / Oxygen 20.95%

/Carbon Dioxide .04% / Other .92%

• Gas, Vapour, Mist, Smoke, Dust & Fumes.

• Entry to The Body

a. Inhalationb. Absorptionc. Ingestion

Inhalation of Gases

Irritants (Ammonia)

Asphyxiates (Nitrogen)

Systemic Poison (CO)

Anaesthetics (H 2 S)

Sensitising Agents (Toluene)

Fire Protection

For combustion to occur there must be three elements present:

a. fuelb. oxygen to support

combustion, andc. heat or a source of ignition

This is known as the “TRIANGLE OF FIRE”. If any one of these elements are removed or are not present, then combustion will not occur

FUEL

HEAT

AIR

Explosive Limits

Lower Explosive Limit (LEL) – in relation to a flammable gas, is the minimum amount of flammable gas required to burn and continue to burn when in contact with a flame.

Upper Explosive Limit (UEL) – in relation to a flammable gas, is the maximum amount of gas which continues to burn when in contact with a flame, any more of which would not support combustion.

Flammable Atmosphere

An atmosphere becomes flammable when the ratio of oxygen to combustible material in the air is neither too rich nor too lean for combustion to occur. Combustible gases or vapors will accumulate when there is inadequate ventilation in areas such as a confined space.

Explosive Ranges

LEAN EXPLOSIVE RICH

0%LEL 100%LEL UEL

Lower Explosive Limit Upper Explosive Limit

Gas

Air

L.E.L. U.E.L.

Flammable Atmosphere

Where the concentration of flammablecontaminant in the atmosphere of a confined

space has been found to be greater than 5% ofits LEL and less than 10% of its LEL then all

personsin the confined space shall be removed unless acontinuous monitoring suitably calibrated gasdetector is used in the confined space at all

times while persons are present.

Flammable Atmosphere

Where the concentration of flammablecontaminant in the atmosphere of a confinedspace has been found to be 10% of its LEL or

greater, persons in the confined space shall beremoved

AS/NZS 2865-2001 10.35

Monitor Readings

%LEL and UEL ACTION

< 5% Area can be accessed

5% or > Prior No access permitted until area ventilated toto Entry reduce level to below 5%

before initial entry

5%-10% During Access allowed to continue if continually Occupation monitored

10% or > Area to be vacated

High/Off/Over/OL No access permitted – area will have littleto no oxygen, and may have an explosive

atmosphere

Workplace Exposure Standards

TIME WEIGHTED AVERAGE (TWA)

The average airborne concentration of aparticular substance when calculated over a

normal eight hour workday, for a five dayworking week.

Workplace Exposure Standards

SHORT TERM EXPOSURE LIMIT (STEL)

A 15 minute TWA exposure which should not be exceeded at any time during a workday

even if the 8 hour TWA average is within the TWA exposure standard.

Exposure at the STEL should not be longer than 15 minutes and should not be repeated more than 4 times a day. There should be at

least 60 minutes betweensuccessive exposures at the STEL.

PEAK

A maximum or peak airborne concentration of a particular substance.

Determined over the shortest analytically practicable period of time, which does not

exceed 15 minutes

Workplace Exposure Standards

There are many toxic contaminants which may be present in a confined space. Not all substances have established Workplace Exposure Standards (sometimes called Permissible Exposure Limits). Some substances may have a TWA but not a STEL; or may have a TWA and STEL but not a peak limitation.

Workplace Exposure Standards do not represent an absolute line between safe and unsafe.

Workplace Exposure Standards – Cautions

Workplace Exposure Standards apply to an average person – some workers may be more susceptible to exposure to toxic contaminants – due to illness or health conditions.

Workplace Exposure Standards change over time. What is considered safe today may not be considered safe in the future.

Exposure to all toxic contaminants should be minimised as much as is practicable.

Workplace Exposure Standards – Cautions

Safety of the Atmosphere

95% of fatalities occur from entering an area that has

not been assessed for the safety of the atmosphere.

The atmosphere of the confined space is to be tested

before any person is permitted to enter the confined

space. AS/NZS 2865 – 2009 indicates that a test be

conducted for:

a. oxygen content

b. airborne concentration of flammable or combustible contaminants.

c. airborne concentration of potentially harmful contaminants

AS 2865-2009

Hydrogen Sulphide

Concentration Symptoms

1ppm / 0.0001% Rotten Egg Gas can be smelt

10ppm / 0.001% This is the TWA. If the concentration goes above this level the area must be evacuated or breathing apparatus worn

15ppm / 0.0015% This is the STEL

100ppm / 0.01% Sense of smell deadened in 15 mins. Eyes and throat start to burn

200ppm / 0.02% Sense of smell deadened in 3 mins

500ppm / 0.05% Central Nervous System attacked, breathing ceases within 15 mins

700ppm / 0.07% Unconscious very quickly, breathing stops1000ppm / 0.1% Unconscious immediately,

irreversible brain damage.

Rotten Egg Gas

ChlorineConcentration Symptoms

0.2-3.5ppm/0.00002%-0.00035% Can be smelt

0.5ppm/0.00005% Peak exposure for 15 min

1ppm/0.0001% TWA exposure for 8 hours

30ppm/0.003% Immediate chest pain,coughing, and vomiting

50ppm/0.005% Pulmonary odema

430ppm/0.043% Fatal exposure in 30 min

1000ppm/0.1% Fatal exposure after a few

deep breaths

Flammable Airborne Contaminants

A flammable contaminant is any dust, fume, mist, vapour or gas present in the air at concentrations that can propagate a flame on contact with an ignition source. 

Flammable contaminants are expressed as: 

Lower Explosive Limit (LEL) The minimum concentration of a flammable gas required to burn and continues to burn when in contact with an ignition source. 

Upper Explosive Limit (UEL): The maximum concentration of a flammable gas which will burn.

• Methane – LEL 5% of atmosphere • Propane – LEL 2.1% of atmosphere• Butane – LEL 1.9% of atmosphere • Hydrogen – LEL 4.0% of atmosphere

1. Press Mode keya. Software – Self Checkb. Serial No, Data Logging c. Low - High Alarms appear d. Type of Sensore. Date and Time

2. Check battery strength. (40% Min)

3. Conduct Fresh Air Calibration.

4. Conduct challenge test. (If required). This test is based on manufacturer recommendations and Company Policy. BUMP (Before Use) CHALLENGE (Monthly) Returns to Zero

5. Attach Pump and test if required.

Atmospheric Monitoring

Method of Test

Never put your head into an open area that has not been assessed for its atmospheric conditions. Once the cover is removed approach from an up-wind direction and monitor from top to bottom.

Ventilation

Ventilation of a confined space should be by natural, forced or mechanical means to establish and maintain a safe atmosphere.

This ventilation should be continued throughout the period of occupancy.

The area must be retested after any period of ventilation to ensure that the ventilation process was adequate.

Liquids

Liquids should be pumped from the area and or the flow of the liquid diverted before testing takes place. If it cannot be removed it should be stirred by means of a mechanical pump or by blowing compressed air through the bottom of the area to release any trapped gases (such as H2S). Manual stirring with a paddle may be inadequate to release any trapped gases.

Method of Test

Never put your head into an open area that has not been assessed for its atmospheric conditions. Once the cover is removed approach from an up-wind direction and monitor from top to bottom.

Questions ?