GHANA INSTITUTE OF MANAGEMENT AND PUBLIC ADMINISTRATION (GIMPA)  COURSE:POST GRADUATE DIPLOMA IN OCCUPATIONAL SAFETY HEALTH AND ENVIRONMENTAL MANAGEMENT PROGRAMME SUBJECT: PRINCIPLES OF OCCUPATIONAL HEALTH MANAGEMENT

SUBJECT: PRINCIPLES OF HEALTH AND SAFETY  TOPIC: INTRODUCTION TO OCCUPATIONAL HEALTH  PRESENTED BY : GERSHON D. ODUM  APRIL 2016

The Goal of the module  The goal of this module is to provide participants with the skills and knowledge required to identify and control occupational health hazards in their working environment.

EXPECTED LEARNING OUTCOMES  At the end of the module, participants should be able to:  Identify the main forms in which chemical and biological hazards occur at the workplace  Outline the ill effects of chemicals and biological hazards.  Recognize the main substance hazard classifications  Explain the purpose and use of chemical data sheets

 Explain the purpose and use of workplace exposure limits.  Carry out risk assessment to identify and control substances hazardous to health at the workplace.  Advise on the general measures for controlling risks to health from chemical and biological hazards at the workplace.

What is a Substance Hazardous to Health?  This term includes any material, mixture or compound used at work or arising from work activities, which is harmful to people’s health in the form in which it occurs in the work activity.

What are Occupational Health Hazards?  These are factors or stresses, arising in and from the workplace which may cause sickness, impaired health and well-being, or significant discomfort and in efficiency among workers.

Categories of Occupational Health Hazards  Occupational hazards are often grouped into the following four categories:  Chemical  Physical  Biological  Ergonomic  This module will however be limited to chemical and biological hazards.

Chemical Hazards  The main forms of chemical hazards in the workplace include:  Dust/Fibres  Fumes  Mists  Fogs  Vapours  Gases  Aerosols  Smoke

Biological Hazards  The main forms of biological hazards in the workplace include:  Insects  Moulds  Fungi  Bacteria  Viruses  Parasites  Snakes

Ill Effects of Chemical and Biological Hazards  The following factors contribute to the ill –health due to chemical and biological hazards at the workplace:  Toxicity  Route of entry  Target organs  Acute and chronic effects  Local and systemic effects

Definition of Toxicity  Toxicity refers to the ability of a substance to produce harm to a living organism.  Toxicity of a substance cannot be eliminated, but the risk of harm occurring to people can be controlled.

What Makes a Substance Toxic?  The toxicity of a substance depends on its:  Quantity or concentration  Duration of exposure  Physical state of the material e.g. particle size  Drug interactions  Affinity for human tissue  Individual variation ( sex, age, race etc.)

 Its solubility in human tissue fluids  Sensitivity to attack of human tissue or organs  Environment (temperature, humidity etc.)

Routes of Entry  The following are methods through which harmful substances can enter the body:  Inhalation - Through the respiratory system  Absorption - Through the skin or eyes  Ingestion – Oral, (Eating Swallowing through the mouth)  Transfer - across placenta to unborn baby

Results of Entry  Entry of substances into the body may result in the following effects:  Diseases of the respiratory system  Cancer and birth defects  Asphyxiation or suffocation  Central nervous system disorders  Damage to specific organs  Blood poisoning  Diseases of the skin

ACUTE HEALTH EFFECTS  Redness, irritation, watery (eyes)  Sneezing, coughing, sore CHRONIC HEALTH EFFECTS  Blindness (eyes)  Nasal & throat cancer (nose & throat)  Corrosion of tooth enamel (teeth)  Loss of brain function behavioural changes to personality & thinking (brain)

Respiratory System Diseases  The following are examples of diseases of the respiratory system:  Pneumoconiosis – inhalation of dust which deposits on the lungs  Silicosis – Inhalation of free silica  Asbestosis – inhalation of asbestos fibres  “Legionnaire,s” – exposure to “Legionella” bacteria

Cancer and Birth Defects  The following are examples of cancer and birth defects:  Carcinogens - cause or promote the development of unwanted cells e.g. asbestos, mineral oil, hardwood dust and arsenic.  Teratogens – cause birth defects by altering genetic material in cells in the reproductive organs and cause abnormal development of the embryo, e.g. organic mercury and lead compounds  Mutagens –Trigger changes affecting future generations.

Asphyxiation  Exclusion of oxygen or direct toxic action e.g. carbon monoxide competes with oxygen for transport in the red blood cells.

Blood Poisoning  Substances such as benzene produce abnormalities in the blood resulting in blood poisoning.

Skin Diseases  The following are examples of diseases of the skin:  Non-infective dermatitis – an inflammation of the skin especially on the hands, wrists and forearms;  Scrotal cancer – produced by rubbing contact with workers’ clothing impregnated with carcinogens such as mineral oil, in close contact with the scrotum.

Target organs  The degree of the toxic effect is not the same in all organs. Each hazardous substance has more affinity for some specific organs in the body. These are known as target organs of toxicity of the particular substance.

Examples of Target Organs  The following are examples of target organs:  Nervous system – attacked by solvents  Skin – attacked by corrosive substances  Lung – attacked by dusts, metal fumes, asbestos, etc.  Blood cells – attacked by benzene, lead,  Liver – attacked by alcohol, chloroform

Allergic Reactions  An allergic reaction may appear after a repeated contact with substances.  Once the sensitisation has been induced, even very low doses can provoke reaction.

Interactions  The effect of simultaneous exposure to two or more chemicals may result in one of the following:  Additive  Multiply  Cancel out

Central Nervous System Disorders  Action on the brain tissue or other organs e.g.  alcohol leading to blindness,  tetra-chloro-ethylene absorbed through the lungs into the blood system causes dizziness, confusion, headache and nausea

Damage to Specific Organs  EXAMPLES:  Brain – Lead, mercury and their compounds  Lungs – Toluene, nitrogen oxides, ammonia,  Nerves – Mercury cadmium and their compounds  Bone marrow – Benzene  Bladder –Auramine, Benzedrine, 2-naphthylamine  Liver- Chlorinated hydrocarbons, dioxane

Long/Short -term Exposures  Acute effects: Immediate responses to single term exposures - (Usually reversible)  Chronic effects - Long term responses to prolonged exposures - (Usually not reversible)

Local and Systemic Effects  Local effect- Harm to a particular part of contact of the body with a hazardous substance e.g. acid or alkali burn on the body.  Systemic effect- movement of a hazardous substance from the point of entry through the circulation system to cause harm to other parts of the body such as the liver and the kidneys.

Methods of Hazard Control  Control of chemical and biological hazards can be achieved through a variety of methods that can be grouped as follows:  Design/Engineering Controls  Administrative controls and work practices  Use of Personal Protective equipment

Design Controls  Hazard control by design is aimed at eliminating the hazard completely and may be achieved by:  Removing the hazardous substance completely  Substituting it with a less hazardous substance  Using it in a less hazardous form e.g.. pellets instead of powder,

Engineering Controls  Engineering controls may be achieved by:  Enclosing the process,  Using partial enclosure and extraction equipment- local exhaust ventilation (LEV)  Providing good general ventilation  Isolating the workers  Using a wetting down process  Shielding of workers against the hazard

Administrative Controls  Using safe systems of work  Trying to reduce the number of workers exposed or the duration of their exposure  Worker education and training

Personal Protective Equipment This should be used as a last resort when no other form of control can be used.

Hazard Classifications  Chemical and biological hazards can be classified in many ways; when discussing or describing them in health and safety terms they are categorized according to the type of harm they can cause.

 Many can fall into more than one category  Some can cause harm after a single exposure or incident, others may have only long-term effects on the body following repeated exposure.

 Very toxic [T+]  Toxic [T]  Corrosive [C]  Harmful [Xn]  Irritant [Xi]  Carcinogenic [-]  Harmful to the environment [N]

Toxics  These are highly hazardous substances which prevent or interfere with body functions in a variety of ways.  They may overload organs such as the liver or kidneys. T

Corrosives  These are substances that destroy living tissues on contact with them. C

Harmful  These are substances which if inhaled, ingested or enter the body through the skin present a limited risk to health.  Their health hazards are less than toxic. Hn

Irritant  These are substances which on immediate or prolonged contact with skin or mucous membrane may cause inflammation. Xi

Carcinogenic  They cause or promote the development of unwanted cells as cancer.

Harmful to the Environment  Substances presenting immediate or delayed danger for one or more components of the aquatic or non aquatic environment. N

Purpose of Safety Data Sheet  It is used to provide information about the substance, the hazards it presents and issues regarding safe storage, use and disposal.

 A chemical safety data sheet provides the following basic information about chemicals: 1.Identification:  Name of the substance or preparation  Name, address and telephone number of the company/supplier/undertaking 2.Composition and information on ingredients

3. Hazards identification 4. First aid measures 5. Fire fighting measures 6. Spillage/accidental release measures 7.Handling and storage 8. Exposure controls and personal protection 9. Physical and chemical properties

10. Stability and reactivity 11. Toxicological information 12. Ecological information 13. Disposal considerations 14. Transport information 15. National regulations and references 16. Other information

Workplace Exposure Limits  An important part of occupational health or hygiene is the measurement of the extent of the hazard.  This is generally done by measuring physical and /or chemical factors, including exposure duration, and relating them to occupational hygiene standards.

 Authorities in several countries publish recommended standards of airborne gases, vapours, dusts, fibers and fumes.  The two primary (English Language) sources are:  The U.K Health and safety Executive (HSE) and  The American Conference of Governmental Industrial Hygienists (ACGIH)

UK Health & Safety Executive (HSE) Standards  The HSE in UK publishes occupational exposure limits annually and as necessary.  The UK standards are essentially in two parts, specifying Maximum Exposure Limits (MELs) and Occupational Exposure Standards (OESs)

Occupational Exposure Standards (OES)  The maximum concentration of an airborne substance, averaged over a reference period ( e.g. 8- hour long-term) to which employees may be exposed by inhalation under any circumstances.  Some substances have been assigned short term MELs ( e.g. 10 minute reference period)  These substances give rise to acute effects and therefore these limits should never be exceeded.

Units of Measurement  MELs and OESs are given in units of parts per million(ppm) and milligrams per cubic meter (mg/m³).  They are given for two periods; long-term exposure (8-hour – time-weighted average (TWA) and short-term exposure (10-minute TWA).  Some substances are designated “SK” which indicates that they can be absorbed through the skin.

Threshold Limit Values  The threshold limit value is the concentration of an airborne substance and represents conditions under which it is believed that nearly all workers may be repeatedly exposed day after day without adverse health effects.  There are different types of TLVs

ACGIH- TLVS  The American Conference of Governmental Industrial Hygienists (ACGIH) publish guidelines known as Threshold Limit Values TLVs.  Four Categories of TLVs are:  1. TLV-TWA  2. TLV-STEL  3. TLV-C  4. TLV-Skin

Time Weighted Average (TLV-TWA)  The average concentration for a normal 8-hour workday or 40 – hour work week to which nearly all workers may be exposed day after day without any adverse effect.

SHORT TERM EXPOSURE LIMIT (TLV – STEL)  The maximum concentration to which workers can be exposed for a short period of time e.g. 15 minutes without any adverse effect.

CEILING (TLV-C)  It is the concentration that should never be exceeded, even instantaneously.

TLV SKIN (TLV-SK)  Indicates substances which can add to the overall exposure by being absorbed through the skin(including mucous membrane and eyes) as well as by other means.

Control of Substances Hazardous to Health (COSHH) Risk Assessment  In many countries such as the UK, duties are imposed upon employers for the protection of employees who may be exposed to substances hazardous to health at work, and of other persons who may be affected with such work.

 An employer is required under law not to carry on any work which is liable to expose any employee to a substance hazardous to health unless a suitable and sufficient assessment has been made of the risks to health created by substances at work and about the measures necessary to control exposure to it.

COSHH Assessment Steps  The assessment is a systematic review of the use of the substance present and consists of the following steps:  Identification of the hazardous properties of the substance  Determination of the quantities used  Identification of persons that can be expected to be exposed

 Determination of their levels of exposure;  Evaluating the risks to those exposed;  Evaluating control measures;  Monitoring the levels of controlled exposure;  Reviewing the assessment at suitable intervals.

 The assessment must be documented and reviewed periodically to ensure its continued suitability.

What Have You Learned?  Identified the main forms in which chemical and biological hazards occur at the workplace  Outlined the ill effects of chemicals and biological hazards.  Recognized the main substance hazard classifications  Explained the purpose and use of chemical data sheets

 Explained the purpose and use of workplace exposure limits.  Carried out risk assessment to identify and control substances hazardous to health at the workplace.  Advised on the general measures for controlling risks to health from chemical and biological hazards at the workplace.

Practice Questions 1. Health hazards in the workplace may be transported by various chemical and biological agents. Describe THREE chemical and THREE biological hazardous agents giving an example in EACH case.

2.For each of the following types of hazardous substance, give a typical examples and identify its primary effect on the body. (i) toxic (ii) corrosive (iii) carcinogenic (iv) irritant

3.(i) Describe the differences between acute and chronic health effects. (ii) Identify the factors that could affect the level of harm experienced by an employee exposed to a toxic substance. (iii) Give TWO acute and TWO chronic health effects on the body from exposure to lead.

4.(i) Define the term toxicity of a hazardous substance. (ii) Identify the factors that determine the toxicity of a hazardous substance.

ANY QUESTIONS?

END OF MODULE THANKS FOR YOUR UNDIVIDED ATTENTION