Medical first aid model course 1 14

Model Course 1.14 Medical First Aid First published as Medical Emergency - First Aid in 1990 by the INTERNATIONAL MARITIME ORGANIZATION Albert Embankment, London SE1 7SR Revised edition 2000 Printed in the United Kingdom by CPC The Printers, Portsmouth 10 ISBN 92-801-6118-0 ACKNOWLEDGEMENTS IMO wishes to express its sincere appreciation to the International Labour Organization and the World Health Organization for their assistance and co-operation in the production of this course In particular, IMO wishes to thank the World Health Organization for permission to utilize relevant parts of the International Medical Guide for Ships as the course compendium Copyright © WHO 1988, IMO 2001 All rights reserved No part of this publication may, for sales purposes, be produced, stored in a retrieval system or transmitted in any form or by any means, electronic, electrostatic, magnetic tape, mechanical, photocopying or otherwise, without prior permission in writing from the International Maritime Organization Contents Page Foô.wonl v uduction Part A: Course Framework Part B: Course Outline and Timetable Part C: DetailedTeachingSyllabus 10 Part D: Instructor Manual 18 Attachment: Guidance on the implementation of model courses 25 Foreword Since its inception the International Maritime Organization has recognized the importance of human resources to the development of the maritime industry and has given the highest priority to assisting developing countries in enhancing their maritime training capabilities through the provision or improvement of maritime training facilities at national and regional levels IMO has also responded to the needs of developing countries for postgraduate training lor senior personnel in administration, ports, shipping companies and maritime training institutes by establishing the World Maritime University in Malmo, Sweden, in 1983 Following the earlier adoption of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers, 1978, a number of IMO Member Governments had suggested that IMO should develop model training courses to assist in the implementation of the Convention and in achieving a more rapid transfer of information and skills regarding new developments in maritime technology IMO training advisers and consultants also subsequently determined from their visits to training establishments in developing countries IIaIthe provision of model courses could help instructors improve the quality of their existing courses and enhance their effectiveness in meeting the requirements of the Convention and implementing the associated Conference and IMO Assembly resolutions In addition, it was appreciated that a comprehensive set of short model courses in various fields of maritime training would supplement the instruction provided by maritime academies and allow administrators and technical specialists already employed in maritime administrations, ports and shipping companies to improve their knowledge and skills in certain specialized fields IMO has therefore developed the current series of model courses in response to these generally identified needs and with the generous assistance of Norway These model courses may be used by any training institution and the Organization is prepared to assist developing countries in implementing any course when the requisite financing is available W A O'NEIL Secretary-General Introduction • Purpose of the model courses The purpose of the IMO model courses is to assist maritime training institutes and their leaching staff in organizing and introducing new training courses, or in enhancing, updating or supplementing existing training material where the quality and effectiveness of the training murses may thereby be improved It is not the intention of the model course programme to present instructors with a rigid 'eaching package" which they are expected to "follow blindly" Nor is it the intention to substitute audiovisual or "programmed" material for the instructor's presence As in all training endeavours, the knowledge, skills and dedication of the instructor are the key components in the transfer of knowledge and skills to those being trained through IMO model course material Because educational systems and the cultural backgrounds of trainees in maritime subjects considerably from country to country, the model course material has been designed to identify the basic entry requirements and trainee target group for each course in universally applicable terms, and the skill necessary to meet the technical intent of IMO conventions and related recommendations V86'/ • Use of the model course To use the model course the instructor should review the course plan and detailed syllabus, taking into account the information provided under the entry standards specified in the course framework The actual level of knowledge and skills and prior technical education of the trainees should be kept in mind during this review, and any areas within the detailed syllabus which may cause difficulties because of differences between the actual trainee entry level and that assumed by the course designer should be identified To compensate for such differences, the instructor is expected to delete from the course, or reduce the emphasis on, items dealing with knowledge or skills already attained by the trainees He should also identify any academic knowledge, skills or technical training which they may not have acquired By analysing the detailed syllabus and the academic knowledge required to allow training in the technical area to proceed, the instructor can design an appropriate pre-entry course or, alternatively, insert the elements of academic knowledge required to support the technical training elements concerned at appropriate points within the technical course Adjustment of the course objectives, scope and content may also be necessary if in your maritime industry the trainees completing the course are to undertake duties which differ from the course objectives specified in the model course Within the course plan the course designers have indicated their assessment of the time which should be allotted to each learning area However, it must be appreciated that these allocations are arbitrary and assume that the trainees have fully met all the entry requirements of the course The instructor should therefore review these assessments and may need to reallocate the time required to achieve each specific learning objective MEDICAL FIRST AID • Lesson plans Having adjusted the course content to suit the trainee intake and any revision of the course objectives, the instructor should draw up lesson plans based on the detailed syllabus The detailed syllabus contains specific references to the textbooks or teaching material proposed to be used in the course An example of a lesson plan is shown in the instructor manual on page 24 Where no adjustment has been found necessary in the learning objectives of the detailed syllabus, the lesson plans may simply consist of the detailed syllabus with keywords or other reminders added to assist the instructor in making his presentation of the material •• Presentation The presentation of concepts and methodologies must be repeated in various ways until the instructor is satisfied, by testing and evaluating the trainee's performance and achievements, that the trainee has attained each specific learning objective or training outcome The syllabus is laid out in learning objective format and each objective specifies a required performance or, what the trainee must be able to as the learning or training outcome Taken as a whole, these objectives aim to meet the knowledge, understanding and proficiency specified in the appropriate tables of the STCW Code • Implementation For the course to run smoothly and to be effective, considerable attention must be paid to the availability and use of: • • • • • • properly qualified instructors support staff rooms and other spaces equipment textbooks, technical papers other reference material Thorough preparation is the key to successful implementation of the course IMO has produced "Guidance on the implementation of IMO model courses", which deals with this aspect in greater detail and is included as an attachment to this course • Training and the STCW 1995 Convention The standards of competence that have to be met by seafarers are defined in Part A of the STCW Code in the Standards of Training, Certification and Watchkeeping for Seafarers Convention, as amended in 1995 This IMO model course has been revised and updated to cover the competences in STCW 1995 It sets out the education and training to achieve those standards set out in Chapter VI Table A-VI/4-1 Part A provides the framework for the course with its aims and objectives and notes on the suggested teaching facilities and equipment A list of useful teaching aids, IMO references and textbooks is also included INTRODUCTION Part B provides an outline of lectures, demonstrations and exercises for the course A suggested timetable is included but from the teaching and learning point of view, it is more important that the trainee achieves the minimum standard of competence defined in the STCW Code than that a strict timetable is followed Depending on their experience and ability, some students will naturally take longer to become proficient in some topics than in others Also included in this section are guidance notes and additional explanations A separate IMO model course addresses Assessment of Competence This course explains the use of various methods for demonstrating competence and criteria for evaluating competence as tabulated in the STCW Code Part e gives the Detailed Teaching Syllabus This is based on the theoretical and practical knowledge specified in the STCW Code It is written as a series of learning objectives, in other words what the trainee is expected to be able to as a result of the teaching and training Each of the objectives is expanded to define a required performance of knowledge, understanding and proficiency IMO references, textbook references and suggested teaching aids are included to assist the teacher in designing lessons The new training requirements for these competences are addressed in the appropriate parts of the detailed teaching syllabus The Convention defines the minimum standards to be maintained in Part A of the STCW Code Mandatory provisions concerning Training and Assessment are given in Section A-I/G of the STCW Code These provisions cover: qualification of instructors; supervisors as assessors; in-service training; assessment of competence; and training and assessment within an institution The corresponding Part B of the STeW Code contains non-mandatory guidance on training and assessment As previously mentioned a separate model course addresses Assessment of Competence and use of the criteria for evaluating competence tabulated in the STCW Code • Refresher Training The Document for Guidance recommends that seafarers who have completed the more advanced medical training and such other seafarers as may be required by a national administration should undergo refresher courses to maintain and update their knowledge at approximately five-year intervals Such refresher training should cover the principal elements of medical first aid, including lifesaving measures, and should also encompass relevant recent developments in medical care and diagnosis • Medical Care Required for Masters and Chief Mates In general the competence required of those who provide the medical care on board exceeds that required of the master and chief mate under Regulation 11/2 The competence required in table 11/2is limited to organizing and managing the provision of medical care on board Masters and chief mates who themselves provide the medical care on board must therefore meet the higher standard in Table VI/4-2 MEDICAL FIRST AID • Responsibilities of Administrations Administrations should ensure that training courses delivered by colleges and academies are such as to ensure officers completing training meet the standards of competence required by STCW Regulation VI/4 • Validation The information contained in this document has been validated by the Sub-Committee on Standards of Training and Watch keeping for use by technical advisors, consultants and experts for the training and certification of seafarers so that the minimum standards implemented may be as uniform as possible Validation in the context of this document means that the Sub-Committee has found no grounds to object to its content The Sub-Committee has not granted its approval to the documents, as it considers that this work must not be regarded as an official interpretation of the Convention In reaching a decision in this regard, the Sub-Committee was guided by the advice of a Validation Group comprised of representatives designated by ILO and IMO Objective 1his syllabus covers the requirements of the 1995 STCW Convention Chapter VI, Section AW4, Table A-VI/4-1 On meeting the minimum standard of competence in medical first aid, a trainee will be competent to apply immediate first aid in the event of accident or illness on board Entry standards For admission to the course seafarers should have completed IMO Model Course No 1.13, Elementary First Aid or attained a similar standard in elementary first aid Course certificate On successful completion of the course and demonstration of competence, a document may be issued certifying that the holder has met the standard of competence specified in Table AVV4-1 of STCW 1995 A certificate may be issued only by centres approved by the Administration Course intake limitations The maximum number of trainees attending each session will depend on the availability of instructors, equipment and facilities available for conducting the training It should not exceed six trainees per instructor Staff requirements The course should preferably be under the control of a qualified medical practitioner assisted by other appropriately trained staff Training facilities and equipment Ordinary classroom facilities and an overhead projector are required for the lectures When making use of audiovisual material such as videos or slides, make sure the appropriate equipment is available Smaller rooms for practical instruction, demonstration and application should be available The following equipment should be available: ship's medical chest with contents (no drugs) various splints, braces, etc dressings, bandages life-size dummy for practical resuscitation training resuscitator MEDICAL FIRST AID Teaching aids (A) A1 Instructor Manual (Part D of the course) A2 Videos: First Aid Series: V1 A Matter of Life and Death (Code No 564) V2 Dealing with Shock (Code No 565) V3 Bone and Muscle Injuries (Code No 566) V4 Dealing with the Unexpected (Code No 567) V5 Oxygen for the Brain - Maintaining the Supply (Code No 568) V6 After Care of Shock (Code No 569) V7 After Care of Fractures, Dislocations and Sprains (Code No 570) V8 Moving Casualties and Dealing with Other Problems (Code No 571) V9 Cold Water Casualty (Code No 527) V10 Man Overboard (Code No 644) Available from: Videotel Marine International Limited 84 Newman Street London W1 P 3LD, UK Tel: +44 (0)20 72991800 Fax: +44 (0)20 7299 1818 e-mail: mail@videotelmail.com URL: www.videotel.co.uk All reference material necesary for the course has been incorporated Compendium (T1) in the Course IMO and other references (R) R1 R2 R3 R4 R5 R6 The International Convention on Standards of Training, Certification and Watchkeeping for Seafarers, 1995 (STCW 1995), 1998 edition (IMO Sales No 938E) Medical Section (pages 111 to 148) of International Code of Signals, 1987 edition (IMO Sales No 994E) Assembly Resolution A.438(XI) - Training and qualification of persons in charge of medical care aboard ship IMO/ILO Document for Guidance, 1985 (IMO Sales No 935E) ILO/IMO/WHO International Medical Guide for Ships (IMGS), 2nd edition, (Geneva, World Health Organization, 1988) (ISBN 924154231 4) Medical First Aid Guide for use in Accidents Involving Dangerous Goods (MFAG) (IMO Sales No 251 E) Details of distributors of IMO publications that maintain a permanent stock of all IMO publications may be found on the IMO website at http://www.imo.org Textbooks (T) T1 A Course Compendium is provided for use as a textbook This contains selected extracts from ILO/IMO/WHO International Medical Guide for Ships (Ref R5) MEDICAL FIRST AID: COMPENDIUM Other medicines Give the dose, if any, recommended on the container, or: • up to and including I year: VIO of the adult dose • 1-4 years: 1;3 of the adult dose • 4-10 years: V2 of the adult dose • 10-15 years: % of the adult dose Standard antibiotic treatment Reference has been made to the following treatment for a number of complaints, using the words "give the standard antibiotic treatment" for the sake of brevity For patients not allergic to penicillin (see: Note on the use of penicillin, this page) If able to take tablets by mouth: • phenoxymethyl penicillin potassium (250-mg tablets) tablets, followed by I tablet every hours for days If unable to take tablets by mouth: • procaine benzylpenicillin, 600 000 units intramuscularly once a day for days For patients allergic to penicillin If able to take tablets by mouth: • erythromycin, 500 mg, followed by erythromycin, 250 mg, every hours for days If vomiting: • 30 minutes before a dose of erythromycin is taken, give one 50-mg cyclizine hydrochloride tablet (to a child aged 1-10 years, give half a tablet; those over 10 years can be given one tablet) Note on the use of penicillin Penicillin is a powerful drug, capable of destroying the germs causing many diseases, but it should not be used lightly since people may become sensitive to it Mild sen&itivity may cause a general disturbance, with transient itching rashes, weals, and swelling of the skin; severe sensitivity may cause fainting, collapse, and even death Severe cases (see Anaphylactic shock, page 167) are rare, but if collapse occurs after the administration of penicillin, give a subcutaneous injection of epinephrine, ml ampoule, immediately Whenever a penicillin injection is given, a sterile syringe and an ampoule of epinephrine should be kept within reach In viewof the danger of sensitivity, it is important always to question a patient about to receivepenicillin on whether he has ever had any reactions to penicillin If he has had such reactions, or may possibly have had them, not give penicillin, either by mouth or by injection, but give erythromycin instead Provide any patient who has been given penicillin and is going to a hospital ashore with a note stating how much penicillin he has had and how and when it has been given Penicillin is usually most effective in acute inflammation Some of the more common causes of acute inflammation at sea are: boils, abscesses,carbuncles, cellulitis, erysipelas; infected wounds and bums; infected ears; tonsillitis and quinsy (peritonsillar abscess); and pneumonia [Note: page 167 of /MGS has not been included in this compendium] 114 Annex joined to one another except for the lower jaw, which moves at joints just in front of the ears Anatomy and The skull rests on the upper end of the backbone, which is made up ofa series of small bones phys.·olo gy placed on top of each other These bones are Treatment of illness on board ship requires some ca!led vertebrae a~d co~lec~ively compose the understanding of the anatomy and physiology spmal column, wlthm whIch IShoused the spmal of the human body cord; nerves emerge from the cord at the level of each vertebra At the lower end of the backbone The pri~cip~1 bones and ~uscles of the b~?y are is the pelvis, formed by the hip-bones, one on shown m FIg 147 and FIg 148, the pOSItIonof either side which together form a basin to supthe main arteries and veins in Fig 1~9, a?d the port the c~ntents of the abdomen On the outer conte~ts of the chest and abdomen m Fig 150 side of either hip is a cup-shaped socket into and FIg 151 which the rounded head of the femur (or thigh Th k letal system bone) fits, forming a ball-and-~ocket joint The es e femur ends at the knee, where It forms a hmgeThe skull forms a case that contains and protects likejoint with the strong tibia (shin-bone) which the brain It consists of many bones, firmly can easily be felt under the skin On the outer MEDICAL FIRST AID: COMPENDIUM side of the shin-bone is attached the slender fibula In front of the knee-joint lies the patella (kneecap), the shape of which can be easily felt At the ankle the foot is joined to the lower ends of both the tibia and fibula by another hinged joint The foot is made up of many small bones of different shapes There are two bones in the great toe and three in each of the other toes Twelve ribs are attached to the backbone on either side Each rib, with the exception of the two lowermost on either side, curves round the chest from the backbone to the sternum (breastbone) in front As can be seen from Fig 147, the lowermost ribs have no attachment to the sternum in front The ribs form the chest and protect the lungs, heart, and other internal organs When you take a deep breath, your ribs move slightly upwards and outwards so as to expand your chest The sternum, flat and dagger-shaped, lies just under the skin of the front of the chest, and to its upper end is attached the clavicle (collar-bone) On either side this bone goes out horizontally to the point of the shoulder and acts like an outrigger in keeping the shoulder in position The outer end of the collarbone joins with the scapula (shoulder-blade), which is a triangular bone lying at the upper and outer part of the back on either side Each scapula has a shallow socket into which fits the rounded upper end of the humerus (arm bone) At the elbow the arm bone forms another hingelike joint with the radius and ulna (the forearm bones), and these join with the hand at the wrist The wrist and hand, like the foot, are made up of many small bones There are two bones in the thumb and three in each finger The muscular system Voluntary muscles are found in the head, neck, limbs, back and walls of the abdomen (Fig 148) They are attached to bones by fibrous tissue which is frequently in the form of a cord and is then called a tendon or leader When a muscle contracts in response to an impulse sent to it through a nerve, it becomes shorter and thicker and draws the bones to which it is at- 116 tached nearer to one another The brain controls such movements Involuntary muscles are found in the stomach and intestines, heart, blood vessels, and other internal organs of the body As the name indicates, they are not under the influence of the will, but function on their own, day and night The circulatory system (heart and blood vessels) The body contains about five litres of blood, which circulates to all the tissues of the body (Fig 149) It is kept moving round the body by the heart, a muscular pump about the size of a clenched fist situated in the chest behind the breastbone, lying between the lungs, rather more on the left than on the right The heart has two sides; the right side receives the venous blood coming back to it from the body in general and pumps it through the lungs, where it passes through minute tubes, gives up carbon dioxide, and takes up a supply of oxygen The oxygenated blood now passes to the left side of the heart, which pumps it to all parts of the body through the arteries This blood carries oxygen, food, water, and salts to the tissues; it is bright red in colour It also conveys heat to all parts of the body and contains various substances to counteract infections in the tissues The arteries are like thick-walled tubes and decrease in diameter away from the heart In the tissues the smallest blood vessels are very minute and are called capillaries The blood, having supplied the tissues with oxygen and other substances and removed the carbon dioxide that has accumulated, becomes darker in colour The capillaries take it into the veins, thin-walled tubes that carry the blood back to the right side of the heart Some of the blood passes to the stomach and intestines and, having taken up food products, carries them away to be stored in the liver Blood is also taken by arteries to the kidneys and there gets rid of waste products, which are passed in the urine As the blood passes along the arteries, they pulsate at the same rate as the heart is pumping The average normal pulse rate is about 70 per minute, but it increases with exercise, nervousness, fear, fever, and various illnesses The pulse is usually counted by feeling the artery at the front of the wrist just above the ball of the thumb The respiratory system Every time a breath is taken, the air (containing oxygen) passes through the nose or mouth and past the larynx or voice-box into the windpipe The windpipe divides into two main tubes called bronchi, each of which then divides up into [Note: pages have been renumbered for the compendium: this is page 343 of IMGS] IMGS ANNEX 1: ANATOMY AND PHYSIOLOGY people think that it is the ribs moving in and out that produce the act of breathing Rib movement does in fact play quite a big part, but the main work is done by the diaphragm moving up and down The diaphragm is a large domeshaped muscle which separates the chest from the abdominal cavity When the diaphragm muscle contracts, its dome becomes flattened and draws down the lungs, causing air to enter them; when it relaxes, the lungs become smaller and the air in them is expelled The muscles of the abdomen also help in breathing When they tighten, they press the abdominal contents against the diaphragm and help in expelling air from the lungs, and when they relax, they assist the diaphragm in drawing down the lungs in breathing in The normal rate of breathing at rest is 16 to 18 times a minute, but it increases considerably with exertion and also with certain diseases, especially those affecting the heart and lungs The digestive system and abdomen many smaller bronchial tubes that pass into the lung tissue The air breathed in passes through these small tubes into minute air cells called alveoli, each of which is surrounded by capillaries The blood in the capillaries gives up carbon dioxide and takes up oxygen In breathing out, the air passes back along the same respiratory passages and is breathed out through the nose or mouth Each lung is covered by a lubricated membrane called the pleura The inner side of the chest wall is lined with the same kind of membrane These two layers of pleura are in contact and slide smoothly over one another during breathing The lungs are rather like elastic sponges, and the many air cells in them expand with breathing in and are compressed with breathing out Most Food in the mouth is broken up by chewing and tongue movements and mixed with saliva (spittle), which lubricates it and starts the digestive processes When it is in a suitable state it passes to the back of the throat, where muscular action forces it down the oesophagus; or gullet, a muscular tube in the neck behind the windpipe The gullet runs down the back of the chest between the two lungs, then passes through the diaphragm into the stomach As may be seen in Fig 151, the stomach lies mainly in the left upper part of the abdominal cavity, partly behind the lower left rib cartilages and just under the heart When food enters the stomach, various digestivejuices act upon it, and the stomach muscles contract and relax, mixing it thoroughly The capacity of the adult stomach is about one litre Still only partly digested, the food passes into the small intestine, where mQre digestive juices, especially those from the liver and pancreas, mix with it Nourishment and fluids are absorbed from this coiled-up tube, which is about six 119 MEDICAL FIRST AID: COMPENDIUM metres long, and the residue of the food passes into the large intestine, or colon, at a point in the lower part of the right side of the abdomen, close to where the appendix is situated In the large intestine more moisture is extracted from the food residue At its far end, the large intestine joins the rectum, and here the unwanted food residue collects and is passed out of the body by the back passage or anus The liver secretes the important digestive juice called bile (a greenish/brownish fluid) and, on its surface, has a small reservoir called the gallbladder, where a supply of bile is kept available The liver also deals with, and stores, digested food materials The spleen (Fig 151) is a solid oval-shaped organ in the upper part of the left side of the abdominal cavity at the back of the stomach, just above the kidney Its functions are largely connected with the blood and it may be enlarged in certain diseases The urinary system (See Fig 140, page 236) The kidneys are at the back of the upper part of the abdominal cavity, one on either side of the spine They remove water and certain waste products from the blood and produce urine Urine leaves each kidney by a small tube called the ureter, the two ureters entering the back of the bladder, which is a muscular bag situated in the front part of the cavity of the pelvis Urine collects in the bladder and is expelled from it through a tube leaving its under-surface This tube is called the urethra and in the male is contained in the penis The nervous system The nervous system consists of the brain, the spinal cord, and the nerves that issue from them The brain, in the cavity of the skull, is a mass of nervous tissue The coordinating centre of the body, it acts like a computer, receiving messages through the incoming (sensory) nerves and the special nerves connected with sight, smell, hearing, etc., deciding on the action necessary, then sending out orders to the various parts of the body by the outgoing (motor) nerves The spinal cord is composed of similar tissue; it leaves the under-surface of the brain through an opening in the base of the skull and passes down a canal in the vertebral column To pursue the analogy with a computer, it contains the trunk lines running between the brain and the various parts of the body and also a number of local nerve centres At intervals down the spinal column, nerve trunks issue from the spinal cord containing both motor and sensory fibres; these nerves make contact with the muscles, which they cause to contract, and with the skin and other organs, where the sensory messages to the brain and spinal column start Autonomic nervous system This is a fine network of nerves which help control the functions of various organs in the body It, too, has local nerve centres, such as the solar plexus, which is situated in the upper part of the abdomen behind the stomach Although connected with certain parts of the brain, it is not controlled by the will but functions automatically day and night It regulates the rate at which the heart pumps, in accordance with the demands of the various bodily systems at any particular time It also helps control the muscles of the stomach and intestine and the rate and depth of breathing Skin The skin covers and protects the body It consists of two layers The outer layer is hard, contains no blood vessels or nerves, and proteCts the inner layer, where the very sensitive nerveendings lie The skin contains numerous sweat glands, the ,roots of the hair, and special glands that lubricate the skin and the hair Sweat consists of water, salt, and other substances Sweating cools the body and helps to , regulate its temperature [Note: page 236 of IMGS has not been included in this compendium] 122 Annex Medical report form for seafarers For completion by ship's doctor or master, and hospital or doctor ashore, in cases of illness or injury affecting seafarers For completion by ship's master: Note Copies of this form should be provided for the seafarers' medical records, ship's master (or his representatives), and hospital/doctor ashore Date Surname of patient other names Date of birth Name of ship Nationality Shipowner Seafarer's registration Name of ship's representative/agent on shore no Address and telephone of ship's representative on shore Shipboard position held no Details of illness or injury Treatment received on board ship (enclose attachments if necessary) Date of onset of illness Date injury occured Date work ceased on board For completion by hospital or examining doctor on shore Diagnosis Date when patient first examined "Full medioal documentation should be attached, as necessary a Annex Disinfection procedures Procedure for disinfection of water systems with chlorine The chlorine compounds that may be used for disinfecting water systems are chlorinated lime high-test calcium hypochlorite or commercially prepared sodium hypochlorite solution Chlorinated lime and sodium hypochlorite solution can be readily purchased As these compounds deteriorate on exposure to air they should be purchased in small containers which should be tightly closed after use All such products should be kept in a cool dark place The following instructions should be followed in the disinfection of potable-water systems by means of chlorine compounds: (a) Thoroughly scrub the storage tanks and flush the tanks and distribution system with potable water Determine the volume of water necessary to fill the tanks and distribution system completely; the amount of disinfecting agent required can then be determined from Table A When chlorine compounds or solutions other than those mentioned in the table are used, the dosages should be adjusted accordingly Table A Amount of chlorine compound required for a 50-ppm (50 mglJitre) solution Capacity of system (including tanks and piping) (Iitres) Amount of chlorine coumpound required Chlorinated lime 25% (kg) High-test calcium hypochlorite 70% (kg) Sodium hypochlorite solution 10% 5% (Iitres) (Iitres) 1000 5000 10000 0.2 10 0.07 0.4 0.7 0.5 2.5 tained (warm water is better than cold for this purpose) Allow the solution to stand for 30 minutes, so that the undissolved particles may settle to the bottom Pour off the clear liquid (the chlorine solution), if necessary filtering it through muslin or cheesecloth High-test calcium hypochlorite Place the required amount in a bucket, fill with water to within a few inches of the top, and· stir until the powder is dissolved (disregard any slight turbidity) Sodium hypochlorite solution No preparation required (h) (c) Prepare the chlorine solution as follows Chlorinated lime Place the appropriate amount of chlorine compound in a clean, dry bucket Add a small amount of water, and mix to a thick paste Dilute the paste by adding water gradually and stirring constantly until 4-8 litres of solution are ob, This procedure has been chosen for inclusion here because of the relative ease with which chlorine compounds can be procured and used for the required purpose There are various alternative methods; disinfection with agents other than chlorine may be preferred or the national health administration may prefer to issue its own instructions (d) Introduce potable-water the chlorine tanks solution into the (e) Immediately after the introduction of the chlorine solution, the tanks should be completeIy filled with potable water The turbulence of the incoming water will generally ensure adequate mixing (f) Open the taps and outlets of the distribution system nearest the storage tanks, and allow the water to flow until chlorinated water appears Working outwards from the tanks, open successively the other taps and outlets until all have been flushed with chlorinated water Care should be taken to ensure that the pressure tank is filled with chlorinated water Since a certain amount of the chlorinated water will have been drawn from the storage tanks, they should be refilled to overflowing, and chlorine solution should be added, if necessary, to make up the concentration in the tanks to 50 ppm (50 mgjl) MEDICAL FIRST AID: COMPENDIUM (g) The chlorinated water should be allowed to remain in the storage tanks and the piping systern for at least hours before it is discharged In an emergency, the contact time may be shortened to I hour by increasing the dosage to 100 ppm (100 mg/I) (h) After this contact period, the tanks and dis- tribution system should be drained and flushed with potable water until the water no longer has an objectionable taste of chlorine (i) Fill the storage tanks with potable water Procedure for disinfection of potable water with chlorine Disinfection of the water, whether regular or intermittent, should be accomplished by methods approved by the national health administration When chlorine is the accepted disinfectant, the following procedure should be used The chlorine should preferably be applied in the form of a hypochlorite solution, using a com-' mercial hypochlorinator designed for the purpose It is desirable to apply the chlorine in direct proportion to the flow rate of the water being treated Therefore, an automatic, proportional control hypochlorinator should be used It should be constructed or equipped so that the flow of the hypochlorite solution may be observed Its capacity should be determined on the basis of the maximum flow rate of the water and the treatment required to produce a satisfactory 128 chlorine residual (not less than 0.2 ppm (0.2 mg/litre) of free chlorine) A sampling cock should be provided at an appropriate place in the system for taking test samples to check the residual chlorine and the operating efficiency of the feeder A commercial testing kit for determining the residual chlorine should be obtained with the hypochlorinator When water is treated regularly by chlorination, provision should be made for a baffled holdingtank of sufficient capacity to provide a suitable contact period for the chlorine and water This period of contact should end before any water is delivered to the next treatment unit or the distribution system, and should be computed on the basis of maximum rate of flow through the contact tank The contact period should be at least 30 minutes, with a free chlorine residual of at least 0.2-0.5 ppm (0.2-0.5 mg/litre) For checking the effectiveness of water chlorination, the residual chlorine present in water sampIes can be estimated by a chlorimetric test Commercial equipment is available for this purpose, and an appropriate kit can be carried on board ship The manufacturer's instructions provided with the kit should be closely followed The use of liquid chlorine presents the hazard of escaping gas, and the space requirements for the acceptable installation and operation of equipment and the storage of reserve cylinders are considerable ... Bibliography 1- 52, 11 5 -12 2 IMO Model Course 1. 13 11 - pp 48, R4 - Sect 17 App.2 51 R4 - Sect 17 App.2 T1 - pp 11 5 -12 2 Required performance: describes and lists the contents of the first- aid kit required... 10 3 -10 8 R4 - Sect 17 App.2 T1 - pp 10 9 -11 4 R4 - Sect 17 App.2 T1 - pp 12 7 -12 8 R4 - Sect 17 App.2 T1 - pp 3, 6, 14 Teaching Aid Required performance: 11 states that radio medical advice is available... rewarming 15 MEDICAL FIRST AID Knowledge, 10 understanding and proficiency Radio medical advice (1 hour) IMO Textbooks, Reference Bibliography R4 - Sect 17 App.2 T1 - pp 10 3 -10 8 R4 - Sect 17 App.2 T1