CASE STUDY 2: HAZARD IDENTIFICATION, RISK ASSESSMENT AND RISK CONTROL

QUESTION 1

A student was heating a test tube containing a mixture of chemical liquids. Instead of heating the mixture gently, he heated it strongly without shaking.After heating, he immediately put the test tube under the nose of a girl standing next to him for her to smell the gas evolved.Both students were not wearing safety spectacles .The hot mixture of chemicals, liquids suddenly squirted out of the test tube onto the left eye and face of the girl, who screamed consequently for help.The laboratory technician immediately took the injury student to the preparation room and washed her left eye and face with distilled water continuously until the ambulance personnel summoned by the school arrived.The injured student was taken to the hospital and given medical treatment. Fortunately, the student’s injuries were not permanent, but she had suffered a great deal of pain and had to take sick leave for a week.

1. Identify the type of hazard

• Chemical hazard

2. List the appropriate steps to prevent the incident from happen in the future.

• Wears safety equipment during experiment
• Watch out for substances that can spark a fire
• Teachers should monitor during experiment is carried out by students

3. List the personnel protective equipment that must be provided to the students before they carried out the experiment.

• Face and eye protection
• Lab-coat and apron
• Gloves
• Foot protection

QUESTION 2

Loud noise at work can damage hearing. Approximately 22 million U.S. workers are exposed to hazardous noise at work. To minimize occupational noise-induced hearing loss, the National Institute for Occupational Safety and Health (NIOSH) recommends that workers should not be exposed to noise at a level that amounts to more than 85 decibels (dBA) for 8 hours.

In most cases, the preferred approach is to eliminate the source of hazardous noise. When elimination is not possible, substitution of the loud equipment for quieter equipment may be the next best alternative to protect workers from hazardous noise. If the hazardous noise cannot be controlled through elimination of the source or substitution of quieter equipment, engineering controls may be installed to reduce noise to safer levels or remove noise at the source.

Engineering controls require physical changes to the workplace such as redesigning equipment to eliminate noise sources and constructing barriers that prevent noise from reaching a worker. If it is not possible to remove the hazard through elimination, substitution or engineering controls, the next step is to reduce noise exposure through the use of administrative controls. For example, an employer may change an employee’s work schedule to avoid too much noise.

Personal protective equipment (PPE), such as ear plugs or other hearing protection devices, is the last option in the hierarchy of control. PPE is generally less effective than elimination, substitution, and engineering controls because they rely on human actions to reduce noise. Used in combination with other levels of control, such as administrative controls, PPE may provide worker protection when engineering controls do not adequately remove the noise hazard.

NIOSH encourages occupational safety and health professionals, employers, and workers to learn more about controls for hazardous noise exposure. Consult a workplace safety and health professional to determine solutions for your work setting and employees.

1. Identify the type of hazard

• Physical Hazard

2. Recommend FIVE (5) solutions to reduce noise at the workplace according to guidelines for Hazard identification, Risk Assessment and Risk Control (HIRARC) by Department of Occupational Safety and Heatlh.

• Elimination - Physically remove the hazard
• Substitution - Replace the hazard
• Engineering controls - Isolate people from the hazard
• Administrative controls - change the way people work
• Personnel Protective Equipment (PPE) - Protect the worker with 

The best way to reduce exposure to noise is to engineer it out at the design stage. In terms of equipment, always try to choose features that will reduce the noise level to a minimum acceptable level. In terms of new installations, select quiet equipment, have a procurement policy that opts for acquiring quiet equipment, and eliminate design flaws which would amplify the noise.

Administrative controls, (such as reducing the length of time the worker is required to work in a noisy area), and the use of personal protective equipment (PPE) are measures that control the noise at the worker. Depending on the type and level of noise; number of workers exposed, and the type of work, engineering controls might not always be considered as reasonable solutions. Where the exposure would not justify the implementation of more expensive solutions, a combination of administrative control (limitation of exposure length) and personal protection equipment may be considered. However, we must keep in mind that the administrative measures and the use of PPE may not be effective in protecting the workers for example PPE may be used incorrectly or may not be used at all, administrative controls may not be followed and more. The use of PPE should be the last resort for controlling the exposure to noise.