RINGKASAN

SEMUA DAERAH YANGMEMPUNYAI AKSES TERBATASDimana gas kimia,uap dan N2 Resiko terhirup kedalam tubuh kitaDapat membahayakan keselamatan/Fatality1. Mengenali Confined SpaceApa Sih ? CONFINEDSPACE ITU MAS ?

1. Mengenali Confined Space

JENIS-JENIS CONFINED SPACEManholesSewersTanksPitsShips HoldsDuctsTunnelsShaftsSilos/VesselsUndergroundPipesColumn

2. Resiko pada confined spaceMengapa saya harus mengetahui tentang confined spaces ?DEMI KESELAMATAN ANDA !Setiap tahun, ratusan pekerja tewas atau terluka di confined spaceKecelakaan sering terjadi dengan cepat & tak terdugaKETIDAK TAHUAN ATAU TERLALU PERCAYA DIRIBiasanya menjadi penyebab kecelakaan. Para pekerja yang tidak tahu atau meremehkan bahaya adalah pekerja yang berisiko

2. The Risks of Confined SpacesKapankah confined space mengandung RESIKO ?SETIAP KALI ANDA AKAN MEMASUKINYA !

Tugas RutinKeadaan DaruratInspeksi, pengujian,pengelasan atau pemeliharaan alatSaat kebocoran kesalahan mekanis dllMembersihkan atau membetul kan vesel, tanks silos dllMenolong teman kerja yang telah terluka taau pingsan

2. Resiko pada confined spaceBahaya pada Confined Spaces1. Ledakan atau kebakaran4. Kekurangan Oksigen3. Gas Kimia dan Uap beracunBahaya UtamaN22.

2. Resiko pada Confined SpaceExplosive DustEntrapmentEngulfmentFloodingPhysical InjuryWeather ConditionsChemical Spills/GasMedical InjuryExtreme HeatNoiseFallsMechanical Faults50cBAHAYA CONFINED SPACES

3. Bahan Kimia Di Confined SpacesApa yang HARUS KITA KETAHUI ? JENIS GAS APA YANG ADA ASAL DARI GAS TERSEBUT APA BAHAYANYA APA YANG AMAN KEMANA GAS ITU BERGERAK BAGAIMANA MEMINDAHKANNYA BAGAIMANA BEKERJA DENGAN AMAN

4. Oxygen Cosentration di Confined Space

O2OXYGEN23.O% VOL.RESIKO MELEDAKJANGAN MASUK !21.O% VOL.KONSENTRASI NORMAL DI UDARA

19.5% VOL.KESULITAN BERNAFASJANGAN MASUK !

4. Oxygen di Confined SpacesO2OXYGENApa yang terjadi bila kita kekurangan Oksigen?

Oxygen (% by volume)

Effects & Symptoms

19.5

Level minimum yang dijinkan

15 19

Kemampuan untuk bekerja normal berkurang

12 14

Denyut nadi naik, kesalahan pada persepsi dan koordinasi

10 12

Pernafasan meningkat, kesalahan penilaian, bibir biru.

8 10

Kesalahan mental, pingsan, muka memucat, mual dan muntah.

6 8

8 menit 100 % fatal

4 - 6

Koma dalam 40 detik, kejang, tewas

TOXTOXIC GASESDEFINITIONSppm = parts per million by volume1% volume = 10,000 ppmTLV = threshold limit value(=Level maksimum yang diijinkan )TWA = time weighted average(selama 8 jam sehari, 5 hari seminggu )STEL = short term exposure limit(selama 15 menit, tidak dari 4 periode per hari )C = ceiling = nilai maksimal yang diijinkanBila 1 detik adalah 1 ppm seperti 1 detik dalam 11 hari !3. Kimia Confined Spaces

H2SHYDROGEN SULPHIDE Gas yang sangat beracun dan mematikan Tidak berwarna Lebih berat dari udara pada konsentrasi tinggi Dapat tersebar melalui angin Berbau seperti telur busuk pada konsentrasi rendah Merusak indera pencium pada konsentrasi tinggi Bdersifat korosif untuk metal tertentu Mudah meledak ( 4.3 45 % vol. ) Dapat dideteksi dengan gas detektor !TWA=10ppmSTEL=15ppm3. Kimia Confined Spaces

H2SHYDROGEN SULPHIDE3. Kimia Confined Spaces

H2S (ppm)

Effects & Symptoms

4.60

Bau tercium

10

Iritasi pada mata

27

Bau menyengat

100

Batuk, iritasi mata

Rusaknya indera pencium

200 300

Peradangan pada saluran pernafasan

500 700

Tidak sadar, kemungkinan fatal dalam 1 jam

700 - 1000

Langsung tidak sadar, pernafasan berhenti, tewas

COCARBON MONOXIDETWA=30ppmSTEL=60ppm3. Kimia Confined Spaces

CO (ppm)

Effects & Symptoms

30

Level eksosure yang diijinkan

200

Tidak nyaman, sakit kepala ringan

400

Sakit kepala berat

1000

Mual, bingung

2000

Kejang

2500

Tidak sadarkan diri

4000

Fatal

CO2CARBON DIOXIDETWA=1%volSTEL=3%vol3. Kimia Confined Spaces

CO2 (% vol.)

Effects & Symptoms

1

Level eksposure yang diijinkan (8 jam)

1-2

Mulai sulit bernafas, sakit kepala & kelelahan

3

Sakit kepala, berkeringat, kurangnya effesiensi

4

Muka memerah, denyut nadi meningkat

5

Depresi mental

6

Tidak dapat bekerja, gangguan penglihatan

8

Kejang, koma & tewas

EXEXPLOSIVE GASESAIRFUELHEATCHEMICAL REACTION3. Kimia Confined Spaces

EXEXPLOSIVE GASESApa arti L.E.L. ?LOWER EXPLOSIVE LIMIT Adalah konsentrasi minimum gas yang harus terdapat di udara agar dapat diledakan UEL adalah upper explosive limit konsentrasi maximum gas yang dapat berada di udara ledakan dapat terjadi3. Kimia Confined Spaces

CH4METHANEUELLELEXPLOSIVETOO WEAKTOO RICH3. Kimia Confined Spaces

CH4METHANECH4ANGGOTA HYDROCARBON Tidak terlihat Lebih ringan diudaraTLV tidak terbatas, bila ada cukup oksigenDapat meledak pada 5 15 volume Dapat dideteksi dengan gas detektor

GAS YANG MUDAH MELEDAK JUGA BISA BERACUN ! JANGAN HANYA MELIHAT L.E.L

4. Prosedur - AdministrasiDarimana Saya MULAI?MEMERIKSA PERATURAN PERUSAHAAN Mengenali semua connfined spaces Mengetahui kemungkinan bahaya yang dihadapi Tutup dan beri tanda yang jelas di semua daerah berbahaya Pastikan bahwa anda mempunyai ijin bekerja yang jelas Patuhi semua peraturan perusahaanBILA ANDA TIDAK MEMILIKI PERATURAN INI WAKTUNYA UNTUK MEMBUAT!!

Persiapan sebelum memulai kerja, ! Pilih peralatan yang diperlukan untuk menggunakan standard & darurat Pastikan bahwa anda memiliki ijin kerja yang jelas Pastikan apa yang harus dialkukan jika terjadi keadaan darurat Training untuk semua orang yang terlibat4. Prosedur - Administrasi

Work Permit / IJIN KERJA ?IJIN KERJA Pengamanan yang harus dilakukan Pekerjaan yang harus dilakukan Ijin masuk ke daerah bersangkutan Sebagai jaminan KEAMANAN ANDA Anda harus mematuhi semua instruksi Ijin kerja harus di tunjukkan di tempat SEBELUM kerja dimulai4. Prosedur - Administrasi

NATURE OF WORKPRECAUTIONSHAZARD IDENTIFICATIONSAFETYREQUESTED BYTOOLS & EQUIPMENT NEEDEDDESCRIPTION OF WORKLOCATION & EQUIPMENT TO BE WORKED ONISOLATION CERTIFICATESGAS TESTINGPERSONAL PROTECTIONCERTIFICATIONAPPROVALSACCEPTANCEPERMIT ISSUEDREVALIDATIONPERMIT COMPLETEDPERMIT SUSPENDEDPERMIT TO WORK FLOWCHART4. Prosedur - Administrasi

GAS TESTING Test semua bahaya (OX EX TOX) Masukkan probe lewat akses ventilasi Buka akses & test ulang Tetap DILUAR pada saat test Test semua area ( atas, bawah, bentuk tak beraturan ) Bila ada gas atau uap berbahaya yang terdeteksi, ventilasi & bersihkan area, kemudian test ulang5. Prosedur - Operasional

VENTILASI Ventilasi semua confined space area dengan udara normal, sesuai prosedur bahkan bila tidak ada bahaya yang terdeteksi Bila memungkinkan, bersihkan residues. Sludge dll, yang dapat mengeluarkan gas berbahaya. Sebelum masuk, bersihkan dengan steam atau air sesuai peraturan perusahaan Cara ventilasi disesuaikan dengan tempat pastikan prosedur yang digunakan sudah sesuai5. Prosedur - Operasional

KERJAHATI - HATI Ikuti semua prosedur Gunakan alat yang tepat Test berulang - ulang Teruskan ventilasi Test semua arah ( atas, bawah, tempat tak beraturan )5. Prosedur - Operasional

TIPS KHUSUS UNTUK SAFETYJangan masuk confined space tanpa ijinMasuk dgn aman - bila anda pengawas dan ingin membantu PPE Jangan merokokTinggalkan tempat Bila anda merasa pusing dan sakit kepalaTest untuk bahaya hanya bila anda terlatihTetap siaga Selalu jangan remehkan keadaanKonsentrasi Setiap ssat, gunakan alat dengan benarSiapkan alat emergency yang tersedia Jangan Memindahkan respirator yang diperlukan saat bekerjaAda pengawas lain - yang siap membantu bila diperlukan5. Prosedur - Operasional

Apa yang harus dilakukan pada KEADAAN DARURAT? Minta tolong Tunggu bantuan sebelum memasuki areaLakukan ventilasi sembari menuggu Pindahkan orang yang terluka Gunakan alat bantuan penyelamatan Beri ventilasi buatanBeri bantuan medis A.S.A.P. Isolasi area hingga penyebab kecelakaan teridentifikasiJANGAN MEMASUKI AREA TANPA SAFETY HARNESS & BREATING APPARATUS5. Prosedur - Operasional

Apa yang DIBUTUHKAN ?1. Gas Detectors2. Safety Lines & Harness3. Breathing ApparatusHAL UTAMA UNTUK BEKERJA

6. Alat Pelindung Personal

Apa yang DIBUTUHKAN? Escape Breathing Apparatus Safety Helmets Gloves Safety Glasses Safety Footwear Lighting Protective Clothing Earplugs6. Alat Pelindung Personal

Peralatan Lain Lowering ropes Barriers Safety locks / Do not operate tags Road cones First Aid Kits Resuscitation Apparatus Distress signal units BA control boards Fire Extinguishers6. Alat Pelindung Personal

Perawatan alatPENTING UNTUK KEAMANAN KERJAPastikan bahwa anda : Mengikuti semua instruksi Semua alat diservice oleh manufacturer setiap beberapa waktu Menyimpan data service yang lengkap dan jelas Memeriksa semua alat dan fungsinya pada saat tidak dipakai 6. Alat Pelindung Personal

Apa guna GAS DETECTOR?1) Memonitor kondisi gas (OX/EX/TOX)2) Menunjukkan konsentrasi3) Memberikan peringatan pada level yang tidak aman4) Bekerja dengan dua cara : Diffusi, untuk pengawasan personal Pompa, Untuk test sebelum masuk7. Gas Detectors

Components of a Gas DetectorOn/Off/Menu KeysFlashing LightOxygen SensorBacklit DisplayToxic Gas Sensor PortsSensor Protection GrilleNicad Rechargeable BatteryExplosive Gas Sensor(IR Sensor)AlarmSampling Pump7. Gas Detectors

8. Breathing ApparatusEscape SetsDrgerRapid AirHoodPushFit Connector1/2 mask & exhalation valveAir HoseContents GaugeCylinderPressure Reducer/Constant Flow ValvePull Pin AssemblyCarry Bag

SensorSelection

ELECTROCHEMICAL SENSORSUntuk gas beracun dan oksigen

CATALYTIC SENSORSUntuk gas yang mudah meledak ( Penggunaan terbatas )

INFRA-RED SENSORSUntuk hidrokarbon dan karbon dioksida( aplikasi khusus, umur sensor yang lama,Tidak perlu oksigen )7. Gas Detectors

WhatFEATURES do INEED?CHECKLIST:1) Multigas Capability2) Suitable for OX / TOX / EX3) Measures the CORRECT toxic gases4) Warning Signal LOUD & BRIGHT5) Simple to operate6) Display clear with backlight7) User Exchangeable SMART Sensors for flexibility / maintenance8) Electronic Pump (suitable for long distance sampling)9) Different sampling options10) Rechargeable Long Lasting Batteries11) Rugged & Long Lasting Unit12) Correct certifications7. Gas Detectors

7. Gas DetectorsSpecialEquipmentIf the oxygen level is below 10% MOST explosive gas sensors will not work. SOLUTION:Use an INFRA RED gas detector that is unaffected by oxygen

Infra Red Sensors measure the C-H bond in hydrocarbons to determine the LEL. The purely physical principal of operation has significant advantages over conventional sensors

7. Gas DetectorsSpecialEquipmentNot all gases & vapours can be measured by an electronic gas detectorSOLUTION:Use the Drger Tube System to measure these gasesThe reagent inside a Drger tube reacts with the gas or vapour & results in a colour change (stain). The length of the colour change determines the concentration

Certification7. Gas DetectorsRFI / EMC ProtectionRadio Frequency Interference - look for CE markingIngress Protection indicates protection against dust & water (EN 60529)IP 54 means dust & splashed water protectedEx approval (intrinsic safety)EEx ia or EEx ib from a suitable certifying body (CENELEC)EEx s for some equipmentor in America UL class 1 division 1, Group A,B,C,DAntistatic Housingprevents accidental sparkingIf your detector has no marked approvals - it probably isnt safe!

8. Breathing ApparatusWhat does Breathing Apparatus do?Breathing Apparatus is your supply of breathing air from a compressed air source - needed whenever the atmosphere is no longer safe to breathe

8. Breathing ApparatusWhat can I use & when do I use it?Self Contained Breathing Apparatusis used whenever the atmosphere is not suitable for normal breathing & for emergency / rescue operationsEscape Setsare used for self rescue from confined spaces when the atmosphere becomes dangerous, they are normally considered to be standard PPE. They are NEVER used for standard operations or for assisted rescueAirline Systemsare for long term use & when entry with a normal SCBA is physically restricted

8. Breathing ApparatusS.C.B.AThe Components of a Self Contained Breathing Apparatus (SCBA)Carbon Composite BackplateFull Face MaskCylinderCarbon Compositeor SteelHarnessLung Demand ValveFisrt Stage Pressure ReducerPressure GaugeCylinder Strap

8. Breathing ApparatusS.C.B.ASPECIAL FEATURES OF AN SCBA:GENERAL1)Composite Backplate for flexibility, with built in carrying straps2)Ergonomic Design3)Warning Whistle integrated with pressure gauge4)Conforming to BS standards5)Antistatic, Flame Retardent & Water Resistant6)High Air Delivery from first pressure reducerMASK1)Push Fit LDV (lung demand valve)2)Double Reflex Seal3)Polycarbonate Demisting Visor4)LDV with extremely low breathing resistanceCYLINDER1)Complete selection of cylinder types & sizes, including double cylinders when needed

8. Breathing ApparatusS.C.B.AHow do I calculate the Working Duration?Litres of Air = Cylinder Capacity Cylinder Pressuree.g. 6 litres 200 bar = 1200 litres

Total Duration = Litres of Air / Breathing Ratee.g. 1200 / 40 litres per minute = 30 minutes

Working Duration = Total Duration - Safety Factore.g. 30 - 10 = A Working Duration of 20 minutes

8. Breathing ApparatusAirline SystemsAirline SystemsRemote Air Supply from mobile cylinder unit or airbank systemTwo workers can be connected to one airline unit using a Y piece connectorFace Mask & LDV are of the same type as a conventional SCBANormally used in conjunction with short duration SCBAs to provide emergency air in the event of failureWorking upto 80 metres away from the Air SourceCylinder rotation allows uninterrupted operationCan be fitted with telecommunication systems

9. VentilatorsVentilatorAir movingAir inAir outDuctingSupply Ventilation

Air inVentilatorAir outDucting

9. VentilatorsVentilatorAir movingAir inAir outDuctingExhaust Ventilation

9. VentilatorsVentilatorHeavier than air contaminantsAir inAir outDual Mechanism Ventilation

Ventilator

10. Special ProceduresSAFE ENTRY INTO SEWERSSEWER ENTRY INVOLVES SPECIAL HAZARDS & NEEDS SPECIAL TRAINING

IF SEWERS ARE NOT PROPERLY SEALED BEFORE ENTRY, THE LEVEL OF TOXIC & EXPLOSIVE GASES CAN CHANGE AT ANY TIME!

REMEMBER THAT SEWER ENTRY MAY OCCUR IN PUBLIC AREAS, SO ISOLATION & MARKING OF THE CONFINED SPACE IS PARTICULARLY IMPORTANT

Sewers

10. Special ProceduresINERTENTRYPROCEDURESO2OXYGENYOUMUSTALWAYSUSEBREATHING APPARATUSYOU MUST CONTINOUSLYGAS TEST THE WORKING AREA

IN INERT AREAS YOUR BREATHING APPARATUS IS YOUR ONLY AIR SUPPLYUSE OF AIRLINE EQUIPMENT WITH BACKUP SCBA IS STRONGLY RECCOMENDED

11. Further TrainingSafe Working in Confined SpacesThe material covered in this document is only the start - further training is recommended for all staff to build up knowledge & confidence - the following are examples of courses that should be takenPermit to Work (1 day)Safety Supervising (2 days)Authorised Gas Tester (2 days)Breathing Apparatus (2 days)First Aid & CPR (2 - 4 days)What else do we need to learn ?

P E N U T U PTERIMA KASIH DAN SELAMAT BEKERJA DAN SEMOGA MATERI INI AKAN BERMANFAAT & TUGAS KITA SELALU MENDAPAT LINDUNGAN DAN PETUNJUK DARI TUHAN YME .. AMIN.

Draeger South East Asia (Malaysia)Page *The information contained in this training folder is for general information only. It is designed to promote an awareness of the hazards encountered in confined spaces & to enable the trainee to prepare a strategy for tackling confined space hazards. It does not certify the reader or make him an expert in confined space entry. Any confined space operation should be carried out in line with the existing regulations of the company, state or country in which the work is carried out.

This folder was prepared by Draeger Malaysia, however considerable assistance was provided from the training manuals of Drger Limited (UK) and the book Safe Working in Confined Spaces for Drger Asia Pacific, written by Mr W.J. Rowe, who has provided invaluable help over the years.

For more information please contact:Draeger South East Asia (Malaysia) Pte Ltd14 Jalan PJS 11/18, Sunway Technology Park, 46150 Petaling Jaya, Malaysia.Tel 03-735-6460; Fax 03-735-4171; E-Mail draeger@tm.net.myDraeger South East Asia (Malaysia)Page *UK Confined Space Regulations state the following:

Confined Space means any place including chamber, tank, vat, silo, pit, trench, sewer, flue, well or similar space in which, by virtue of its enclosed nature, there arises a reasonably foreseeable specified risk.

Specified Risk means a risk of:a) serious injury to any person at work arising from a fire or explosionb) without prejudice to a)i) the loss of consciousness of any person at work arising from an increase in body temperatureii) the loss of consciousness or asphyxiation of any person at work arising from gas, fume, vapour or lack of oxygenc) the drowning of any person at work arising from an increase in the level of liquidd) the asphyxiation of any person at work arising from a free flowing solid or the inability to reach a respirable environment due to entrapment by a free flowing solidDraeger South East Asia (Malaysia)Page *Confined Spaces exist in many settings, but are especially common in storage & transport facilities.

Underground areas & enclosed areas are the most recognisable confined spaces, BUT ANY PLACE can become a confined space under certain conditions.

For example:AN OPEN TOPPED DITCH or VAULT becomes a confined space if air circulation inside is poor and a gas thats heavier than air accumulates at the bottom.

A STRUCTURE OF IRREGULAR SHAPE becomes a confined space if pockets of gas or vapour accumulate where air doesnt circulate.

If you are in doubt, consider the space a confined space - and treat it accordingly until it is proved otherwise!Draeger South East Asia (Malaysia)Page *Confined Space Accidents CAN BE PREVENTED!

You MUST:

1) KNOW the hazards you face on the job.2) LEARN how to detect & deal with these hazards.3) FOLLOW established safety procedures for work in confined areas.

Examples of Confined Spaces in MY COMPANY INCLUDE:Draeger South East Asia (Malaysia)Page *EVERY TIME YOU ENTER A CONFINED SPACE A HEALTHY RESPECT FOR THE HAZARDS IS ESSENTIAL

DANGER CAN ONLY BE REDUCED BY ADOPTING A SAFE SYSTEM OF WORK!Draeger South East Asia (Malaysia)Page *EXPLOSION - a build up of flammable gases or vapours can burn or explode.Gases & vapours can be formed by scale or residue inside the confined space, by solvents used for cleaning, decomposition of organic materials etc.A spark or open flame can cause flammable gases to igniteOperations such as oxypropane cutting may create an excess of oxygen (enrichment) - increasing the danger of spontaneous combustionTOXIC GASES & VAPOURSOperations previously done inside a confined space may have produced toxic gases - which still remainOperations in progress inside a confined space, such as cleaning, welding, painting et. Can produce dangerous fumesSome toxic gases are VERY dangerous because you cant see or smell themOXYGEN - when the level is too low, life is threatenedOxygen deficiency can be caused by - oxidation, rusting, fire, growth of bacteria or displacement by another gasIt is especially dangerous because it can cause drowsiness or euphoria - keeping you from realising the danger in time to escapeDraeger South East Asia (Malaysia)Page *The above list is not exhaustive - as well as applying the rules for confined space - remember that all operations need safety procedures, which you should continue practicing.

Dont forget the potential for physical injuries in confined spaces - caused by road traffic, faulty equipment, misuse of equipment, ladders, slips, tripping - etc.

SPECIAL HAZARDS IN MY COMPANY INCLUDE:Draeger South East Asia (Malaysia)Page *A CHECKLIST:1) What was stored in the confined space in normal use?

2) Where any chemicals used during the last confined space entry?

3) What chemicals will I be using in the confined space (e.g. cleaning fluids, paints, welding fumes)?

4) Is there any external source of chemicals (e.g. contaminated water in a sewer)

5) Do I know the nature of the chemicals (explosive / toxic)?

6) Do I have the safety data sheets of the chemicals?Draeger South East Asia (Malaysia)Page *Oxygen normally constitutes 20.9% volume of the atmospheric gases, the majority being Nitrogen (78%) plus some carbon dioxide (0.03%), water vapour, carbon monoxide & noble gases.

In major cities (such as Kuala Lumpur) it is quite common for the oxygen level to be depleted (down as low as 20.6%) due to pollution.Please note that oxygen deficiency can effect the reliability of gas detectors (See section on gas detection)

Oxygen is measured with an ELECTROCHEMICAL SENSOR normally in the range 0 - 25 % by volume as this covers the full series of hazards.

Different countries / companies differ on the limits for safe work.Normally 23 or 23.5 % is set as the upper limit& 19, 19.5 or 20.0 % as the lower limit

Draeger South East Asia (Malaysia)Page *GAS CLOUD MOVEMENT:

Vapours & gases move from place to place under two influences - GRAVITY, when clouds heavier than air will flow in a manner similar to liquids; & TURBULENCE / VENTILATION which governs the movement of gas clouds of neutral bouyancy (such as oxygen).

It is important to consider the following variables when determining the movement of gases:

Direction of the prevailing wind (for external protection)Nature of the ventilation systemTemperature & Density of gasesPressure within vessels & pipelinesNature of the structureDraeger South East Asia (Malaysia)Page *Common examples of toxic gases include:-

H2S - Hydrogen SulphideCO - Carbon MonoxideCO2 - Carbon MonoxideCl2 - ChlorineSO2 - Sulphur DioxideNH3 - AmmoniaC6H6 - BenzeneMany V.O.Cs (Volatile Aromatic Hydrocarbons) - which are also explosive. More than 500 hundred other gases & vapours!Two useful sources on the permissible limits of toxic gases are the US NIOSH guide to Chemical Hazards & the ACGIH (American Conference of Governmental Industrial Hygeinists) guide to Threshold Limit Values. The MSDS sheets also show the acceptable levels.

Draeger South East Asia (Malaysia)Page *Hydrogen Sulphide is found in oil & natural gas & is a danger in many refining & petrochemical plants. It is also commonly produced in standard chemical processes. The second major source of H2S comes from sewage where it is a natural breakdown product.

Although H2S smells of rotten eggs at low concentrations, but it may have a sickly sweet/sour smell at slightly higher concentrations. At even higher concentrations there IS NO SMELL at all because the olfactory nerve becomes paralysed.

It is also important to note that H2S and alcohol dont mix - studies have shown that people can be overcome by extremely low H2S concentrations after drinking.Draeger South East Asia (Malaysia)Page *How does H2S affect people?-After breathing in, H2S goes directly to the lungs & from there enters the blood stream. In order to protect itself the body utilises its natural defence mechanisms & oxidises the H2S into a harmless compound.

As the concentration increases the body can no longer oxidise all the H2S, so it begins to travel freely in the blood stream & poisoning begins. The nerve centres in the brain that control breathing are paralysed. As a result the lungs stop operating & death occurs by asphyxiation.

H2S is one type of CHEMICAL ASPHYXIANT - working by action on the nerves.

This is quite different to a SIMPLE ASPHYXIANT which operates by hypoxia - simple reduction of oxygen in the lungs.

Draeger South East Asia (Malaysia)Page *How does CO affect people?-Carbon Monoxide combines with the haemoglobin in red blood cells to form a very stable compound (carboxy-haemoglobin) thus preventing further uptake of oxygen in the blood. This reaction can occur very rapidly.

Like H2S, CO is a CHEMICAL ASPHYXIANT, but this time it operates by interfering with oxygen transport.

Carbon Monoxide is commonly formed by incomplete oxidation - the major source being the internal combustion engine. Be especially cautious of operating any machinery in a confined space that uses combustion as an operating principle - if it is unavoidable the exhaust should be vented well out of the confined space - & dont forget that combustion uses up oxygen at the same time!

CO is a colourless & odourless gas - slightly lighter than air.Draeger South East Asia (Malaysia)Page *Carbon Dioxide is naturally present in the air, and is a product of respiration (we naturally breathe out about 4% carbon dioxide). It is also clear that the acceptable levels of CO2 are much higher than H2S or CO. However, many people are not aware that CO2 is toxic (It affects the respiratory centre of the brain - increasing depth & rate of breathing). There are many sources of this gas, and being denser than air it easily collects in low lying areas. Because CO2 affects the way we think, once again there is a specific danger of not realising the hazard before it is too late.

CO2 is one of the major causes of sick building syndrome which occurs when the ventilation in a building is poor or inadequate - very similar to a confined space!Draeger South East Asia (Malaysia)Page *Combustion is a CHEMICAL REACTION between FUEL & OXYGEN (air) with heat providing the energy to start the reaction. Remember that heat does not necessarily mean a flame - static sparking or heat produced by process equipment is perfectly adequate!USEFUL TERMS to remember include:FLASH POINT - the lowest temperature at which there is sufficient vapourisation of a substance to produce a vapour which will flash (explode) when a flame is applied. Flash points only exist for substances that are liquids at room temperature. Aviation fuel has a flash point at 37.8c. Remember that the temperature in Asian countries is much higher (& closer to the flash point) than in more temperate climates.

IGNITION TEMPERATURE - is the lowest temperature at which heat from a burning vapour is capable of producing more vapour for combustion to continue.

AUTO IGNITION TEMPERATURE - is the lowest temperature at which a substance will ignite spontaneously, no separate ignition is neededDraeger South East Asia (Malaysia)Page *The LEL varies from gas to gas, for example:Acetylene 1.5% vol.Benzene1.2% vol.Hydrogen4.0% vol.Propane2.0% vol.Xylene1.1% vol.Propane2.0% vol.White Spirit1.1% vol.LEL OF GASES IN MY COMPANY:

It is also worth noting that there are several gases which have no UEL - they contain enough oxygen in the molecule to support combustion, or are unstable compounds. Acetylene is one of these gases.Draeger South East Asia (Malaysia)Page *The above example shows the explosive range of methane; 100% LEL corresponding to 5% by volume.

Whilst it is theoretically true that anything upto 100% LEL is safe; practically it is not sensible to use this. Remember:

1) The response of a gas meter to different gases varies (see overleaf)2) Gas concentration varies from place to placeFor this reason the alarms (warnings) on a gas detector are set well below the LEL.Normally we use:A1 (first response alarm)set at10% LELA2 (second alarm)set at 20% LELAlthough under certain circumstances it may be advisable to raise (20/40) or lower (5/10) these limits. Draeger South East Asia (Malaysia)Page *Methane is one member of the hydrocarbon chain & as well as being a common industrial gas & fuel is also produced by rotting materials.

Ideally it would be ideal to have a gas detector that can determine all the combustible gases present & calculate the precise LEL - but in fact it is not possible to do this.

Explosive Gas Detectors normally use a CATALYTIC sensor. The principle is to use a heated coil or bead coated with a catalytic material. As the gas enters the sensor it reacts with oxygen, aided by the catalyst. The resulting temperature change generates the signal.

Catalytic Sensors are normally calibrated to an individual gas - For safety reasons this is normally the gas that the instrument is LEAST sensitive too, thus although the reading is innacurate, the display always shows an LEL value that is the same or HIGHER than the real LEL.Draeger South East Asia (Malaysia)Page *Though situations are always different, there are some basic safety measures you should ALWAYS take - as outlined on the following pages:-

Because the dangers of confined spaces are at NOT EASILY DETECTABLE -

ASSUME HAZARDS ARE PRESENTuntil youre sure theyre notALWAYS THINK SAFETY FIRST!

Draeger South East Asia (Malaysia)Page *Draeger South East Asia (Malaysia)Page *The format of the permit should normally be the same within each company, permits generally being classified as follows:-

1) Hot Work - Class 1tightly controlled, for working in hazardous areas & involving the use of naked flames or sparking equipment, this work normally requires isolation or manual setting of the fire detection & extinguishing system.2) Hot Work - Class 2Similar to class 1, but less tightly controlled - normally involves use of equipment that COULD cause a spark -e.g. non intrinsically safe equipment.3) Cold WorkWork involving hazardous jobs that could not involve a fire or explosion - e.g. working with scaffolding.4) Confined Space WorkFor operation in confined spaces5) Excavation

The confined space permit can (and often is) used in conjunction with other permits. It is normal that 3 copies of the permit are made - One is kept with the issuing authority, the other in the control room & the other posted at site in a clear plastic folder.Draeger South East Asia (Malaysia)Page *HAZARDS IDENTIFIED can mean:-1) Is the atmosphere safe to work in?2) Is there a risk of fire or explosion?3) Is there a risk of personal injury or death?4) Is there a possibility of damage to other equipment?5) Is there a risk of leakage of liquids/gas or live electricity?6) Is there a spillover risk to other areas?7) Is there a risk to the environment?SAFETY PRECAUTIONS can mean:-1) Isolation of fuel lines, electrical points, instrumentation, hydraulic lines2) Fire Extinguisher / Fire Blanket / Fire Watch needed3) Gas Test required4) Air blower needed5) Nitrogen purging needed6) Scaffold needed7)NO ENTRY / NO SMOKING signs8) Area Barriered Off9) Extra Illumination10) Sprinkler / Fire Detection isolatedDraeger South East Asia (Malaysia)Page *Make sure that the equipment you are using has been calibrated by the manufacturer & is certified as suchTest the equipment's function before entryEnsure that the unit is chargedEnsure that you have the correct probes for useCheck in the following order:1) Oxygen2) Explosive Gases3) Toxic GasesMake sure that you are using the right equipment with the right sensors for the job

The Gas Test should only be done by someone who is authorised to use the equipment & understand the results. If you are in any doubt - get someone else to confirm the measurement.Draeger South East Asia (Malaysia)Page *Make sure that the ventilator you are using has been approved for the workCheck what gases you are ventilating & carry out the work accordinglyFollow the procedure for ventilationMake use of all entry & exit holes for ventilation

Ensure that you are not:1) Sucking the contaminated air into a breathing area2) Recirculating the contaminated air back into the confined space

More information can be found in the section on ventilation equipment

Ventilation is often continued during operation - apart from the standard safety reasons for doing this, it can also help cool the confined space & make the atmosphere more pleasant to work in.

Draeger South East Asia (Malaysia)Page *Know and follow ALL correct procedures for your job. Wear all appropriate, required protection and safety devices, even if the exposure time is brief. If a respirator is required, enter with it on. Maintain constant communication with observers.

Use only whats safe for the particular environment. For example use hand tools with minimum sparking potential, explosion proof tools & protective equipment where flammable fumes & gases may be present.

Test immediately after entering - even if no hazards were detected from the outside. Test frequently while working -- especially if using solvents. Test before every new entry (for example, after breaks & lunch) and after ventilating.

Ventilate entire area while working, especially when using solvents, combustibles or open flame.Draeger South East Asia (Malaysia)Page *Draeger South East Asia (Malaysia)Page *This course does NOT deal with the following areas:

1) Fire Detection Equipment2) Fire Fighting Apparatus3) General First Aid4) Safety Harnesses & Lifting Equipment5) CPR Equipment6) Manual Cardiac Resuscitation (Mouth to Mouth)

MAKE SURE THAT YOU ARE TRAINED TO USE THIS EQUIPMENT & CAN CARRY OUT EMERGENCY WORK UNDER THE CONDITIONSDraeger South East Asia (Malaysia)Page *All the above equipment requires specialist knowledge. You should always get yourselves & your staff trained to use the equipment you use.

If possible you should obtain specialist training from the manufacturer & you should always read the manual!

Draeger South East Asia (Malaysia)Page *Always ensure that you read the instructions for use as specified by the manufacturer enabling you to wear, use & maintain the equipment to the highest standard - thereby maximizing your personal protection whilst working in or around a hazardous environment.Draeger South East Asia (Malaysia)Page *BA control boards are now considered essential equipment for all teams using breathing apparatus. A tally for each BA includes the following information:NameCylinder PressureTime set was started upThe tally is slotted into the BA controller (a board with slots for the BA tallys and space opposite to log in and out, with a digital clock & duration tables for cylinders) When a personnel enters the area the tag is slotted in and the information is noted down:Time InTime to leaveLocation of userA BA controller oversees the use of the board & monitors the work in progress

Distress Signal Units (DSUs) are movement detectors that give an extremely loud alarm if the user becomes motionless for more than 30 seconds. They can also be manually operated as a distress signal in emergency. Modern Breathing Apparatus sometimes incorporate the DSU into an electronic pressure gauge for a complete personal safety system.

Draeger South East Asia (Malaysia)Page *The Servicing of Breathing Apparatus & Gas Detectors is a crucial area. You should never have to trust your life to unserviced equipment.

Gas Detectors need to be calibrated frequently (normally every three months) for accurate functioning. This is a skilled job & unless you have been trained, you should leave the work for experts. Any person who carries out the work should be able to provide certification on demand stating that they have all the correct knowledge to perform the work. If you are working with calibration gases always ensure that the use by date is not exceeded.

Breathing Apparatus (from Drger) is essentially maintenance free, but this does not mean you can forget about checking you equipment. Always clean & inspect the parts after use & store the equipment properly. Normally BA sets should be serviced by the manufacturer every year; the pressure reducer overhauled every 6 years & the the cylinders recertified (hydrostatic testing) every 3 or 5 years.

Draeger South East Asia (Malaysia)Page *Draeger South East Asia (Malaysia)Page *The sensors operate in normal mode by diffusion (that is, air & gases can naturally move in and out of the sensor without being forced or pumped). The signal generated by the sensors is processed & displayed on the screen. If the gas concentration exceeds any preset levels (normally there are two settings for each sensor) then an alarm (audible & visible) is generated.

The pump, which can be integral or separate to the unit is only needed when remote sampling is being performed. This draws an air sample through the probe & flows it onto the sensors.

Particular attention should be paid to the delay time when using a pump. In addition to the expected delay as the gas travels through the probe, certain toxic gases (such as H2S) can stick or be absorbed onto the probe material. This can be prevented by using special materials such as viton where the affects are not so accute. The equipment should always come with information stating this delay time. It is normal to sample for at least 5 MINUTES before recording any values (and even longer if sampling for distances greater than 10 metres).Draeger South East Asia (Malaysia)Page *Escape Sets are generally available in 5, 10 or 15 minute versions.They normally work on the principal of constant flow although positive pressure sets are available as well.

Better Units have the following special features:-

High Visibility Hood, including half mask with exhalation valve to reduce CO2 build-up and visor misting.Push fit connector on the hood, enabling the user to breathe fresh air once the duration of the set is finished or when the user reaches fresh air.Easy use instructions on the carry bag enabling even unskilled workers to don the unit rapidly.Optional black carry bag for better antistatic properties.Flame retardent hood and carry bag.

Draeger South East Asia (Malaysia)Page *Most gas detectors are fitted with one catalytic sensor & three electrochemical sensors (e.g. Drger Miniwarn) allowing simultaneous measurement of oxygen, explosive gases & any of two toxic gases. The electrochemical sensors should be smart - that is they contain an electronic memory that records all the sensor & calibration information. This allows the user to remove / replace sensors as required without having the instrument recalibrated, saving both time & money.

Infra Red sensors are normally used instead of catalytic sensors (when measuring hydrocarbons) or in addition (when measuring Carbon Dioxide) - so that the gas detector can now measure upto 5 different gases simultaneously.

Always pay particular attention to the lifetime of the sensors - they will not last for ever! You should always check the warranty provided - it should be a minimum of two years for effective use.Draeger South East Asia (Malaysia)Page *In addition the following features are needed:1) Instrument Management to warn when sensor calibration is due & when faults occur2) Compensation for humidity, temperature & pressure in the sensors3) Operating at high temperatures (65c) and humidity (95%) - most equipment is manufactured in foreign countries where the climate is less aggressive. Always check that you select the correct probes for use - for vertical entry (top-down) flexible tubing is used (viton if needed) & fitted with a float probe that prevents the pump sucking in fluids that would damage the instrument. For horizontal entry telescopic probes are available - in stainless steel or flexible plastic versions.

Also useful is a leather carrying case, water & dust filter to protect the sensors when sampling & spare batteries (check that it is possible to change the battery in a hazardous area)Draeger South East Asia (Malaysia)Page *Infra Red Sensors have the following specific advantages:

1) They do not need oxygen to function2) They cannot be poisoned (catalytic sensors can)3) They are extremely stable (frequent calibration is not necessary)4) They are unaffected by temperature, dust & humidity5) They are more sensitive to large hydrocarbon molecules than catalytic sensors6) They have an extremely long lifetime (in excess of ten years)

However the cost is more than for conventional equipment & they do not measure hydrogen & some other inorganic flammable gases.Draeger South East Asia (Malaysia)Page *Drger Tubes are quite different to conventional gas monitors - they are SPOT reading devices & do not give alarms when the gas level is too high, so particular care must be made when evaluating the reading.

There are more than 250 different types of Drger tube, and in total more than 500 gases & vapours can be measured. Each tube is for a specific gas (as stated on the tube). The measurement is done by breaking off the glass tips of the tube, inserting the tube into the pump (an arrow on the tube indicates the direction of insertion) and then squeezing the pump a predetermined number of times (as indicated on the tube. When this is completed the concentration can be read from the scale on the side of the tube. Each tube is for one measurement only.

Options include the use of automatic pumps & extension hoses so that the measurement can be made remotely. Extension hoses come in various lengths upto 15 metres.

Drger Tubes are normally supplied in packets of ten pieces.Draeger South East Asia (Malaysia)Page *Ingress protection runs from 0 - 6 for dusts (this is the first number) where 0 = no protection & 6 = dust tight; For water it is 0 - 8 where 0 = no protection & 8 = indefinite immersion.

ia and ib refer to intrinsic safetyia classified equipment can be used in zone 0 1 or 2 - in areas where there is continuous hazard (>1000 hours a year - NOT COMMON!)ib classified equipment can be used in zone 1 or 2 - where there is an intermittent hazard (upto 1000 hours a year) - this is normally acceptable for confined space use.

S is a special approval given for gas detectors where the equipment cannot by its nature be intrinsically safe, but still offers a similar level of protection.

The instrument should be antistatic with & without any casing - please check with the manufacturer.Draeger South East Asia (Malaysia)Page *Draeger South East Asia (Malaysia)Page *The respiratory protection equipment in this chapter is all of the compressed air type; giving the user the highest level of protection - vital for work in atmospheres that may be immediately fatal to an unprotected person.

There are four main types of compressed gas breathing apparatus:1) Equipment incorporating a full face piece or air-fed suit, supplied by a compressed air line (AIRLINE SYSTEMS)2)Open Circuit self contained breathing apparatus in which air is supplied from high pressure cylinders worn by the user (SCBA)3)Closed Circuit self contained breathing apparatus, where oxygen is supplied from high pressure cylinders (or chemical reaction) worn by the user. The exhaled breath is recycled and passed through a carbon dioxide absorber to be recirculated with additional oxygen to the face piece (not dealt with here)4) Self Contained breathing apparatus for escape purposes, available in compressed air & compressed oxygen types and used for short durations (ESCAPE SETS)Draeger South East Asia (Malaysia)Page *There are two main methods of supplying compressed-air to the user:1) Negative pressure demand, in which the suction generated in the facepiece during inhalation opens a demand valve and allows air into the facepiece from the compressed air supply.2) Positive pressure demand, is designed to maintain a pressure slightly above atmospheric inside the facepiece, even when the wearer is inhaling. However, maximum flow through the demand valve may be less than the peak inhalation flow required at high physical work rates, so positive pressure may not be maintained at all times.

It is generally considered that the best protection is given by positive pressure sets & this type has almost completely replaced the negative pressure system.

Draeger South East Asia (Malaysia)Page *Examples of sets that conform to the above standards include the Drger PA90 plus series.

Modern sets such as the Drger PSS series have backplates that can rotate with the user & balance the weight between the hips & the shoulders, thus reducing fatigue & easing mobility.

Carbon Composite Cylinders offer a considerable reduction in weight - a major benefit for the user & especially helpful for emergency work. The downside is a cost increase, but where this is important the conventional steel cylinder remains the natural choice.

Remember that cylinders need to be refilled & the contents checked regularly - please ensure that your compressor is adequate for refilling or that your BA supplier can offer the service. It is highly reccomended that one spare cylinder is kept for every BA set to be used as backup & in emergencies

Draeger South East Asia (Malaysia)Page *EXAMPLE:A 9 litre 300 bar cylinder gives a working duration of:9*300/40 - 10 = 57.5 minutes

GENERAL DETAILS FOR USE OF SCBA:BA should only be worn by suitably trained personnelBA teams must consist of AT LEAST TWO MENA BA wearer must never enter a hazardous area aloneBA must be donned and started up in fresh airBA is not to be worn for entry in a hazardous area if the pressure gauge indicates less than 80% full.BA wearers are responsible for carrying out all pre-entry testsBA wearers are responsible for handing their tally in to the BA controller prior to entry in a hazardous area & for collecting it upon leavingIf a distress signal alarm is heard all teams should stop work & assist the injured

Draeger South East Asia (Malaysia)Page *Airline systems are generally used for long duration work. Like SCBAs they operate on the positive pressure system & the function of the apparatus is very similar to a conventional BA.

If an airline is to be used alone (without SCBA) then a harness is worn by the user to support the weight of the airline hose. It is not permitted to attach the LDV directly to the airline.

It is not normally permitted to use an airline without an individual backup supply in confined spaces - this type of work is normally carried out only when the personnel are in full sight of the controller & can make oral contact.

Communication is important when using airline equipment - if a comm. set is not used then a signalling system should be established using short pulls of the airlineDraeger South East Asia (Malaysia)Page *There are two main types of mechanical ventilation:1) General or Supply VentilationFlushes the atmosphere by supplying and exhausting large volumes of air. This method does not reduce the amount of contaminants released - so its use is limited. This is an excellent method for providing breathable air & for controlling low concentrations of toxic materials.

2) Local Exhaust VentilationCaptures contaminants at their point of origin and removes them. This is the best method for controlling flammable & toxic materials produced at a single point, but it does not work well when the contaminants are widely dispersed or in awkward shaped spaces

It is quite common to use both methods in conjunction in order to provide the best ventilation solution.Draeger South East Asia (Malaysia)Page *Most ventilators are either:-1) Electric (powered) models2) Air driven (using a nearby source of compressed air)

The operation of a ventilator is fairly simple. They normally use a straight through fan assembly - fresh air is drawn in at the intake & ejected through the exhaust. This means that the unit can be used for both methods of ventilation - blowing & exhausting.Please ensure that the model chosen has the correct certification for use in the area in which the work is to be done.

In addition to the ventilator, ducting is also required to bring the fresh air to desired area, or suck the contaminated air from a specific point.

Manhole duct adaptors can be fitted if the means of escape from the confined space is the same as the ventilation inlet pointDraeger South East Asia (Malaysia)Page *SPECIAL SAFETY TIPS FOR VENTILATORS:Always use fresh air for ventilation - NEVER OXYGEN!All electrical ventilation equipment must be earthedVentilation equipment should be electrically bonded to the confined spaceIntrinsically safe equipment should be used when exhausting flammable mixturesMake sure that the air intake is far away from any toxic materials - for example the exhaust of a petrol engine.NEVER ALLOW THE EXHAUST TO BE REVENTED INTO THE SPACE - this can be prevented by correct use of ducting.Use a gas detector to monitor the exhaust gas - if the meter indicates flammable or toxic gas take suitable precautionsRemove all ignition sources from the area if the exhaust is potentially flammable.Filter the exhaust if necesarry to prevent air pollutionPlace the outlet downwind so the gas is dispersed quickly - but dont endanger other personnelDraeger South East Asia (Malaysia)Page *Remember to:Check that no dangerous effluents can be discharged into the sewerSwitch the upstream pumping station off & isolate the pumps & valvesBlock all potential sewage entry pointsMake provisions for summoning emergency assistance - e.g. with onsite telephone etc.

Sewer workers are particularly prone to a disease called Leptospirosis (also called Weils Disease or Leptospiral Jaundice). Humans can contract this infection from rat urine & infected rodents. The following precautions should be taken:Rodent controlWear protective clothingWear rubber boots & glovesClean & disinfect, protect all cuts & scratchesWatch out for flu symptoms, headaches, chills & fever - these are early signsDraeger South East Asia (Malaysia)Page *INERT means inactive, and the term is used for gases that do not react chemically. Examples include nitrogen, helium, carbon monoxide & some products of combustion.

INERT entry is carried out for two reasons:1) To reduce the risk of fire or explosion2) To protect material inside the confined space that can easily be damaged or react (for example the catalytic material inside reactor vessels).

On board ships inert gas is produced from the flue gas, which is cleaned and cooled before being transferred to the area (Please note that this gas is not only free from oxygen, but also TOXIC)

In other applications nitrogen is used as a purging gas.

Draeger South East Asia (Malaysia)Page *TEST YOUR KNOWLEDGE SO FAR!!Answer true or false to the following questions:1) A confined space ALWAYS poses some risk2) A permit to work is essential for working in a confined space3) If you need a respirator, you should put it on AFTER entering the confined space4) Safety equipment should be checked before each use5) Poor air circulation can turn ANY place into a confined space6) Its not important to clean and ventilate confined spaces before entry7) A lack of oxygen is the only hazard found in confined spaces8) Its essential to have at least one observer outside the confined space you are working in9) Its OK to remove your respirator briefly while working in a confined space10) Lack of knowledge is a major cause of accidents in confined spaces