industrial hygiene

Pamantasan ng Lungsod ng Maynila College of Engineering and Technology Department of Chemical Engineering

INDUSTRIAL HYGIENE

Submitted by:

Dacaimat, Carlos Miguel C.

San Pascual, Jan Ram D.

BSChE III

Submitted to:

Engr. Clydelle M. Rondaris

Date Submitted:

February 4, 2015

Industrial Hygiene


INTRODUCTION

Industrial hygiene (also referred as Occupational Hygiene) has been defined as “the science and art devoted to the anticipation, recognition, evaluation, and control of those environmental factors or stresses arising in or from the workplace, which may cause sickness, impaired health and well-being, or significant discomfort among workers or among the citizens of the community.” Industrial hygienists use environmental monitoring and analytical methods to detect the extent of worker exposure and employ engineering, work practice controls, and other methods to control potential health hazards.

Occupational hygiene focuses essentially on a preventative approach through the minimization of exposure to chemical, physical and biological agents in the work environment and the adoption of good ergonomic practices. In the occupational health field there are a number of specialist health protection disciplines, other than occupational hygiene, which play an important role in the endeavor to protect the health of employees, customers, contractors and the public who may be affected by the work activities.

Anticipation

Anticipation involves identifying potential hazards in the workplace before they are introduced.

Recognition

Recognition involves identifying the potential hazard that a chemical, physical or biological agent poses to health.

Evaluation

Evaluation involves measurement of the personal exposure of a worker to the hazard/agent in the workplace, particularly at the relevant interface between the environment and the body, e.g. breathing zone, hearing zone, and assessment of the data in terms of recommended occupational exposure limits (OEL).

Controls

Controls involves management of the risks in the environment.

Industrial Hygiene


HISTORY AND DEVELOPMENT

5th Century BC Industrial diseases have been known about since Hippocrates there is even evidence to show that occupational diseases were recognized by the ancient Egyptians. Over time the recognition of links between occupation and ill health has increased and the associations strengthened. In parallel with this techniques were developed to evaluate and control the risks.

1700s The Industrial Revolution Period began which lead to increasing number of establishments and a great demand for workers.

Bernardo Ramazzini, known as the "father of industrial medicine," published in Italy the first comprehensive book on industrial medicine, De Morbis Artificum Diatriba (The Diseases of Workmen). The book contained accurate descriptions of the occupational diseases of most of the workers of his time.

Ulrich Ellenborg published a pamphlet on occupational diseases and injuries among gold miners. Ellenborg also wrote about the toxicity of carbon monoxide, mercury, lead, and nitric acid.

1900s The United States of America (USA) began increasing their public awareness in occupational hygiene. Dr. Alice Hamilton became the first industrial toxicologist the pioneer of toxicology and occupational hygiene.

The American Occupation in the Philippines began the spread of knowledge on industrial hygiene. Until they understood the tropical environment as the greatest danger, they sought to help their fellow colonizers to acclimate. Later, as their attention shifted to the role of microbial pathogens, colonial scientists came to view the Filipino people as a contaminated race, and they launched public health initiatives to reform Filipinos’ personal hygiene practices and social conduct.

1975 The Presidential Decree (PD) 856 or The Code on Sanitation of the Philippines was amended. It became the basic foundation of the modern occupational safety standards in the Philippines.

ASSESSMENT OF HEALTH RISKS

Industrial Hygiene


Assessment of health risks primarily concerned with the health of the employees located in a workplace. It refers to the analysis, identification, and the measurement of workplace hazards or stresses that can cause sickness, impaired health, or significant discomfort in workers through chemical, physical, ergonomic, or biological exposures.

When undertaking risk assessments, it is important to have a clear understanding of the differences between hazard and risk. A hazard is something that can cause harm if not controlled. The outcome is the harm that results from an uncontrolled hazard. While a risk is a combination of the probability that a particular outcome will occur and the severity of the harm involved.

ASSESSMENT OF HEALTH RISKS

1. Define the extent of the assessment

This may involve one or more activities as well as one or more workers at a time. It may also be necessary to assess different hazards as part of different assessments, for instance, noise assessments are usually conducted separately

Industrial Hygiene


from chemical risk assessments as they involve very different approaches. However, when assessing hazards from chemicals such as solvents it is often possible to group any chemicals under one assessment, as they possess similar properties and require similar controls.

2. Gather Information

An assessment of the health risks in the workplace necessitates an appreciation of a number of factors in the decision making process. This first step information pertaining to the factors has to be gathered if a meaningful assessment is to be undertaken. The following are some factors that must greatly considered:

The Nature of the Operation. The Substances used. The form(s), location of the substances used in the workplace The type of job in the workplace The types and extent of occupational exposures Work pattern Operating practices Workers’ Experience and Health background

3. Assess Exposure/Risks

This involves keen inquiry and observation. An assessment should be 'suitable and sufficient'. It should be conducted by a 'competent person' and the type of individual that constitutes such a person will vary from one workplace to another. In some cases the assistance of a fully qualified occupational hygienist will be necessary because of the more complex nature of the risk(s) being investigated.

4. Identify/Carry Out the Actions

Where the assessment indicates a risk to health, it is necessary to specify the steps to be taken to achieve effective control. This is an important part of the assessment, which must be addressed in order to achieve a 100% safe working. It is important to ensure that recommendations from any assessment are implemented properly. Many assessments fail to control exposure because the actions are not implemented.

5. Record the Assessment

Industrial Hygiene


Although assessments are important in the preventative approach to health protection, they are only of limited value unless they are recorded in writing, and dated and signed by the assessor. The quality of an assessment is also likely to be enhanced when verification of verbal information pertaining to fundamental aspects of the assessment can be obtained, in one form or another, and documented.

6. Review the Assessment

The initial assessment should not be regarded as being relevant forever. Periodic re-assessments should be undertaken regularly and in any event whenever it is suspected that the assessment is no longer valid.

HEALTH SURVEILLANCE

Health Surveillance is a generic term which includes any procedure undertaken to assess, review or monitor an individual’s health in order to identify or detect any significant change from normality.

There are three reasons for health surveillance at work:

To ensure adverse health effects related to the work are identified at an early stage;

To ensure continued medical fitness for specific tasks like diving or firefighting,

To promote general health.The decision to undertake health surveillance depends on the findings of a

health risk assessment and it should only take place when exposure could result in an adverse health effect or disease and where there are valid techniques for detecting the effect or disease.

The purposes of health surveillance are: To maintain good health by the early detection of adverse changes

attributed to the exposure, To assist in the evaluation of the effectiveness of control measures, To collect data relevant to the detection and evaluation of hazards

to health.

Health surveillance techniques should be highly sensitive and specific in their ability to detect effects at an early and reversible stage. They should be safe, preferably non-invasive and acceptable to the employee. Cost is also a consideration.

Results of health surveillance should lead to some action of benefit to the health of employees and the methods of recording and analysis of results and criteria and options for action should be established before starting out.

Industrial Hygiene


Biological Monitoring (Physical Examination)

Biological monitoring is an integral part of health surveillance and is the measurement of human tissues, fluids or behavior in comparison with what is considered to be a normal range of values. Measurements on individuals must be treated as measurements made in clinical practice and medical confidentiality applies.

Biological monitoring can show up susceptible individuals, via sampling techniques, analysis and quality control, uptake within or outside acceptable levels and high exposure groups of people who may have been missed by environmental monitoring.

Biological measurements can determine: The content of a toxic material or its metabolite (particularly in blood,

urine and breath) Early reversible tissue change Physiological changes Immunological changes

The following are the common biological materials which are commonly monitored or tested for health surveillance:

Urine Blood Skin

Eyes Ears Lungs

In the Philippines, under Chapter 7, Rule 5, Section 4 of the Sanitary Code of the Philippines:

All workers, irrespective of age and sex, shall undergo physical examination:

(1)before entering employment for the first time;

(2)periodically, or at such intervals as may be necessary account of the conditions or risks involved in the work,

(3)when transferred or separated from employment; and

(4)When injured or ill.

Industrial Hygiene


All examinations shall:

(1)be complete and thorough

(2)be rendered free of charge to the workers; and

(3)include X-ray or laboratory examinations When necessary due to the peculiar nature of the employment.

GENERAL CONTROLS TO HEALTH RISKS

Elimination/Substitution

The most effective form of prevention control is simply to either eliminate the use of the hazardous agent, or the actual process in which it is used. This is clearly not often practicable, but quite commonly hazardous agents or processes can be substituted with relatively innocuous ones.

Examples: Benzene replaced with toluene. Carbon tetrachloride replaced with methyl chloroform. Talc replaced with chalk. Sand blasting replaced by steel shot blasting.

Isolation

Wherever possible processes or operations, which involve some risk(s) to health, should be completely enclosed, with the operator(s) outside the enclosure.

Segregation

Hazardous processes or operations etc. can be segregated from lower risk ones by placing them, for example, at the far end of a workshop, in a separate room, or in a separate building, thereby minimizing the number of workers at risk.

Administrative Controls

Administrative controls relate to how the interaction between personnel and the process/operation are organized. Great care is needed to ensure that procedures, once adopted, are observed; particularly in the longer term, as shortcuts and non-observance can become “custom and practice‟ over time, and once established can be difficult to overcome.

Industrial Hygiene


Sometimes the hazardous operation can be conducted during the evening or night shift when fewer workers are around to be exposed. Job rotation is another method of “protecting‟ personnel, through controlling work patterns. The worker can often influence the extent to which they are exposed to airborne contaminants, e.g. for welding, via stance and/or working upwind of the weld.

Housekeeping

Good housekeeping is particularly important in processes and laboratories where hazardous materials may be handled. Clear labelling, with relevant health and safety advice, careful and appropriate storage and good work techniques all need to be addressed.

Personal factors are essential parts of all control strategies and are associated with the management aspects from both the perspective of how the employer manages his employees, and how the employees manage themselves

Information, Instruction and Training

Education of employees on any health hazards in the workplace and the importance of correctly using all the control measures provided, adopting recommended operating procedures and wearing personal protection, if required, is needed in order to minimize the health risks. Induction courses, regular publicity, health and safety committees and positive line management can all play important roles in education.

Personal Protective Equipment (PPE)

PPE is normally considered to be the last resort and only applicable when the preceding measures are insufficient or not reasonably practicable in achieving a satisfactory work situation. Careful consideration must be given to the choice of the PPE device. It is important that the protection is effective and comfortable; most personal protective equipment is not comfortable for extended use. Regular maintenance is vital for many types of PPE if effective protection is be obtained. PPE management programs need to be adopted whenever the option of PPE use is deemed necessary, and very pro-active ongoing support to the program will be required.

ERGONOMICS

Ergonomics is about the interactions of people with the machines they operate and their working environment. It aims to maximize human performance and to minimize discomfort, dissatisfaction and the risk of musculoskeletal injury.

Industrial Hygiene


Simply put, ergonomics is all about fitting the task to the worker. If the match is poor, the best solution is to redesign the work tasks to make them more compatible with human characteristics. It is less effective to try to change employee characteristics, for example by improving selection and training;

A good fit between technological, organizational and human factors is clearly a goal if good business performance is to be delivered. If these factors can be balanced productivity will improve, resulting in a competitive advantage together with health and safety benefits.

The ergonomics generally covers the following: manual handling of loads; tasks involving repetitive actions; the use of display screen equipment, such as when working with

computers.

Manual Handling

Manual handling means the transporting or supporting of a load (including the lifting, putting down, pushing, pulling, carrying or moving) by hand or bodily force.

An assessment may be best carried out by those most familiar with the operations, such as supervisors and operators, or it may be conducted by professionals in health and safety, occupational hygiene or ergonomics, or by a team.An assessment should consider the entirety of an operation.

The four critical factors which needs great consideration the task; the load; the working environment; and the capabilities of the individual.

Method of Reducing Risk

Solutions may involve changing the position or height of the task, for example by providing adjustable tables or seating to improve posture. Often solutions involve the use of handling aids: whilst an element of manual handling is retained, bodily forces are applied more efficiently, thereby reducing the risk of injury.

Industrial Hygiene


Repetitive Tasks

It refer to the tasks that involve repeated movements can lead to disorders of the muscles, joints and tendons, even when the individual actions do not involve excessive load or force.

Possible effects from doing such repetitive tasks: Repetitive Strain Injuries (RSI) Cumulative Trauma Disorders (CTD) Related Upper Limb Disorders (WRULD)


Some of the methods of reducing risk in some repetitive tasks are the following

Avoid exposure to ergonomic risks where possible. Reduce the risk by automating routine tasks or providing tools

such as powered screwdrivers. Introduce safe working procedures such as regular recovery

breaks and limiting the time on a job. Provide information on the risks and instruction and training in safe working procedures.

Display Screen Equipment (DSE)

Display Screen Equipment (DSE) is a device or equipment that has an alphanumeric or graphic display screen, regardless of the display process involved; it includes both conventional display screens and those used in emerging technologies such as laptops, touch-screens and other similar devices.

Many types of computerized equipment used in laboratories, factories, offices and home working incorporate a display screen and some kind of data entry device such as a keyboard or mouse. These

Industrial Hygiene


arrangements can create several categories of ergonomic risks and provide a good illustration of the need to tackle ergonomic issues in a holistic manner.

Possible Effects of Using DSEs Postural Problems Visual Problems Fatigue and Stress


Some of the methods of reducing risk when using DSEs on a daily basis are the following:

Breaks or changes in activities. Follow the typical office workstation posture (See figure)

Source: US Government via WikiMedia

HYGIENE STANDARDS AND OCCUPATIONAL EXPOSURE LIMITS(Rule on Occupational Health by DOLE)

Occupational Exposure Limits (OELs) are useful measures with which exposures to chemical and physical agents in the workplace environment can be compared. There are three (3) main types of hygiene standards. These include those for chemical agents, physical agents,

Threshold Limit Value

Industrial Hygiene


Threshold Limit Values refer to airborne concentration of substances and represent conditions under which it is believed that nearly all workers may be repeatedly exposed daily without adverse effect.

a) Threshold Limit Value for Airborne Contaminants

All employees exposure to any material specified in Table 8 and Table 8a of the Occupational Safety and Standards of the Department of Labor and Employment of this Rule shall be limited in accordance to the following:

Source: OSHS-DOLE (For a full list of Table 8, see full document at http://www.oshc.dole.gov.ph/)

(1)Materials with names preceded by “C”

Ceiling Values:

An employee’s exposure to any material in Table 8, the name which is preceded by a “C” (e.g. Boron triflouride), shall at no time exceed the ceiling value given for that material in the Table.

Industrial Hygiene


(2)Other Materials, 8-hour Time Weighted Average:

An employee’s exposure to any material in Table 8, the name of which is not preceded by a “C” and any material listed in Table 8a in any 8-hour workshift shall not exceed the 8 hour time weighted average limit given for that material in the Table. However, for a shortperiod of time an excursion in the TLV value in the Table may be allowed but should not exceed the following:

a.from 0 to I concentration by 3 times;b.from I to I 0 concentration by 2 times;c.from over 10 to 100 concentration by 1 ½ times;d.from over 100 to 1000 concentration by 1 ¼ times

(3)“SKIN” Notation:

Listed substances followed by the designation “Skin’ (e.g., DDT-Skin) refer to the potential contribution to the overall exposure by the cutaneous route including mucous membrane and eye, either by airborne or particularly by direct contact with the substance. This attention calling designation is intended to suggest appropriate measures for the prevention of cutaneous absorption so that the threshold limit is not validated.

Ventilation

Ventilation is a method of controlling the environment with air flow. Ventilation is one of the most important engineering controls available to the industrial hygienist for improving or maintaining the quality of the air in the occupational work environment. Ventilation is addressed in specific standards for the general industries. The following factors must be considered for a proper ventilation in a workplace:

Atmospheric Condition Air Supply Cleanliness Air Movement Temperature and Humidity

Industrial Hygiene


Industrial Hygiene

industrial hygiene

Documents

occupational diseases

occupational hygiene

occupational health

ill health

potential health hazards

health of employees

impaired health

recognition recognition