INTRODUCTION

Good afternoon everyone. I am John Kevin San Jose, and here are my groupmates Jeric Inocencio and

Kenneth Contreras and we are group 2. So today we will discuss four topics namely Chemical Safety,

Benzene, Hydrogen Sulfide, and Material Safety Data Sheet.

CHEMICAL SAFETY

Before working on anything, we must ensure our safety, and that hazards are minimized or best,

eliminated. Most especially on working with chemicals, a splash can burn your skin, and worse, one wromg

inhale and you’re dead.

SLIDE 1: IMPORTANCE OF CHEMICAL SAFETY

So first up, I want to ask you “What is the Importance of Chemical Safety?”. Anyone?

First, it ensures that we are working with negligible level of chemical exposure. Be it fumes or liquids. It

doesn’t necessarily mean that all the vapors are gone or eliminated, but the level is already at acceptable

conditions.

Second would be to reduce the probability of an accident. Before working, we should anticipate what are

the hazards and what corrective actions that can be done to prevent those hazards from happening.

And last is to reduce the potential consequences.

SLIDE 2: RISK ASSESMENT

A chemical risk assessment follows the same steps as a risk assessment for any other hazards in your

workplace. There are three basic steps:

1. Identify the hazard: This involves identifying the chemicals you have in your workplace and the

hazards associated with them.

2. Assess the risk: This involves assessing the risk from chemicals or processes in your workplace.

3. Control the exposure: This involves considering the various recognized control measures to

eliminate or reduce the risk.

SLIDE 3: EMPLOYERS AND EMPLOYEES

Employers are required to:

• Determine which hazardous substances are present in the workplace.

• Assess the risks to employees and others from the presence of these hazardous substances.

• Prevent or control exposure to the hazardous substances to as low a level as is reasonably

practicable.

• Have arrangements in place to deal with accidents, incidents and emergencies.

• Provide information, training and consultation to employees.

• Make available health surveillance to employees.

Employees also have duties. They must:

• Co-operate with their employer e.g. follow procedures.

• Make full and proper use of control measures e.g. using extract ventilation where provided, and

report any defects.

• Report any defects in plant/ equipment immediately to the employer as appropriate.

• Report any accident or incident which may have resulted in the release of a dangerous

chemical/substance into the workplace.

SLIDE 4: HOW CHEMICALS ENTER THE BODY

Chemicals are present in every workplace. Even in the cleanest, most modern office, employees may be

routinely exposed to inks, toners and adhesives not to mention a wide range of chemicals used in cleaning

and maintenance.

Chemicals can exist in many forms:

• Dust, fumes, fibres, powders.

• Liquids.

• Gases, vapours, mists.

Chemicals can cause many different types of harm, ranging from mild skin irritation to cancer. The effects

of hazardous chemicals may be seen immediately after contact, or following a single short exposure.

Therefore, it is important to minimise exposure to chemicals at all times.

In order for a chemical to be hazardous to a person’s health, it must either be in contact with or enter the

body.

There are four ways chemicals can enter the body:

• Inhalation: Breathing in contaminated air is the most common way that workplace chemicals enter

the body.

• Contact with the skin or eyes: Some chemicals can damage the skin or eyes (e.g. irritation) or

pass through the skin into the body.

• Ingestion: Workplace chemicals may be swallowed accidentally if food or hands are

contaminated.

• Injection: Injection can occur when a sharp object (e.g. needle) punctures the skin and injects a

chemical directly into the bloodstream.

•

SLIDE 5: HOW CHEMICALS AFFECT OUR BODY?

Here are some examples of how chemicals can affect the body.

Effects on brain and nervous system For example, exposure to pesticides, mercury, lead, solvents, carbon

monoxide gas.

Eye, nose and throat irritation (dryness, soreness or pain) For example, Exposure to acid mists and

vapours, welding fumes or diesel exhaust.

Effects on the lung Lung damage due to asbestos (lung cancer), welding fume (chronic obstructive

pulmonary disease). Irritant induced asthma For example acids (“burn effect” on airways). Allergic asthma

For example flour dust, isocyanate (in 2-pack paints), wood dust.

Liver damage For example, exposure to vinyl chloride.

Bladder damage For example, exposure to some azo dyes (bladder cancer).

Effects on skin Allergic contact dermatitis due to nickel, latex, chromate (found in some cements). Irritant

contact dermatitis because of solvents, detergents, oils, lubricants.

Effects on blood and bone marrow For example, Exposure to benzene in petrol fumes (anaemia and

leukaemia).

SLIDE 6: HAZARDOUS CHEMICALS IN THE REFINERY

SLIDE 15: FIRE DIAMOND

"NFPA 704: Standard System for the Identification of the Hazards of Materials for Emergency

Response" is a standard maintained by the U.S.-based National Fire Protection Association.

First "tentatively adopted as a guide" in 1960, and revised several times since then, it defines the

colloquial "fire diamond" used by emergency personnel to quickly and easily identify the risks

posed by hazardous materials.

This helps determine what, if any, special equipment should be used, procedures followed, or

precautions taken during the initial stages of an emergency response.

The four divisions are typically color-coded with red indicating flammability, blue indicating level of health

hazard, yellow for chemical reactivity, and white containing codes for special hazards.

Each of health, flammability and reactivity is rated on a scale from 0 (no hazard) to 4 (severe risk). The

numeric values are designated in the standard by "Degree of Hazard" using Arabic numerals (1, 2, 3, 4)

FLAMMABILITY

Materials that will not burn under typical fire conditions TO Will rapidly or completely vaporize at normal

atmospheric pressure and temperature.

HEALTH

Poses no health hazard TO Very short exposure could cause death or major residual injury.

REACTIVITY

Normally stable TO Readily capable of detonation or explosive decomposition at normal temperatures and

pressures.

SPECIAL NOTICE

OX Oxidizer

W Reacts with water in unusal manner

SA simple asphyxiant

COR Corrosive

BIO Biological Hazard

POI Poisonous

RAD Radioactive

CRYO Cryogenic

HYDROGEN SULFIDE

SLIDE 1: WHAT IS HYDROGEN SULFIDE?

So what is this infamous Hydrogen Sulfide? What is it made of? And why it can kill you in an instant?

Hydrogen Sulfide is a chemical compound made of one sulphur atom and two hydrogen atoms.

Hydrogen sulphide is a naturally occurring compound present in natural gas, crude oil, volcanic eruption,

hot spring, decaying organic matter. Here in PBR, the sulphur present in the crude is recovered at SRUs to

prevent the formation of H2S. H2S can also be present on confined spaces, and areas where there is a low

concentration of oxygen like swamps, sewers, and polluted waters.

SLIDE 2: CHARACTERISTICS OF HYDROGEN SULFIDE

Hydrogen sulfide is a colorless gas with the characteristic foul odor of rotten eggs; it is heavier than air,

soluble I most organic liquids, and very poisonous, corrosive, flammable, and explosive.

It has a boiling point of -60.7oC and has a melting point of -85.5oC. It’s atomic mass os 34.08 g/mol and

has a density of 1.393 g/L.

SLIDE 3: HAZARDS OF H2S

Acidic solutions with H2S maycause skin and eye irritation

Compressed H2S gas may cause frostbite upon skin contact

Very toxic. May be fatal if inhaled

SLIDE 4:

Hydrogen sulfide is considered a broad-spectrum poison, meaning that it can poison several different

systems in the body, although the nervous system is most affected. The toxicity of H2S is comparable with

that of carbon monoxide. It forms a complex bond with iron in the mitochondrial cytochrome enzymes, thus

preventing cellular respiration.

Since hydrogen sulfide occurs naturally in the body, the environment and the gut, enzymes exist in the

body capable of detoxifying it by oxidation to (harmless) sulfate. Hence, low levels of hydrogen sulfide may

be tolerated indefinitely.

At some threshold level, believed to average around 300–350 ppm, the oxidative enzymes become

overwhelmed. Many personal safety gas detectors, such as those used by utility, sewage and

petrochemical workers, are set to alarm at as low as 5 to 10 ppm and to go into high alarm at 15 ppm.

Exposure to lower concentrations can result in eye irritation, a sore throat and cough, nausea, shortness of

breath, and fluid in the lungs (pulmonary edema). These effects are believed to be due to the fact that

hydrogen sulfide combines with alkali present in moist surface tissues to form sodium sulfide, a caustic.

These symptoms usually go away in a few weeks.

Long-term, low-level exposure may result in fatigue, loss of appetite, headaches, irritability, poor memory,

and dizziness. Chronic exposure to low level H2S (around 2 ppm) has been implicated in increased

miscarriage and reproductive health issues.

Short-term, high-level exposure can induce immediate collapse, with loss of breathing and a high

probability of death. If death does not occur, high exposure to hydrogen sulfide can lead to cortical

pseudolaminar necrosis, degeneration of the basal ganglia and cerebral edema. Although respiratory

paralysis may be immediate, it can also be delayed up to 72 hours.

SLIDE 6 AND 7: EXPOSURE LIMITS

OSHA established exposure limits to hydrogen sulphide.

The Permissive Eposure Limit or PEL is at 10ppm, based on 8 hour-day per 5 day work week.

While the Short-Term Exposure Limit is at 15 ppm on a 15 minute work period.

SLIDE 8 : SAFETY CONTROL AND EQUIPMENT

We can prevent inhaling hydrogen sulphide by establishing different safety control and equipment.

The first one is the

Fixed Monitor and Safety Alarm

Portable Monitors

Gas sacks

Proper PPEs like SCBA

Natural and Mechanical Ventilation