Occupational Health Practice Questions

Q: The decibel level above which auditory fatigue occurs is:

85 dB. **Explanation:** The correct answer is **85 dB**. This threshold is a critical physiological marker in audiology and occupational health. **1. Why 85 dB is correct:** Auditory fatigue, also known as a Temporary Threshold Shift (TTS), occurs when exposure to loud sounds causes a temporary decrease in hearing sensitivity. The cochlear hair cells become metabolic exhausted and overworked. Research and occupational safety standards (like OSHA and NIOSH) establish **85 dB** as the critical intensity level. Prolonged exposure to sounds at or above this level leads to auditory fatigue, and if the exposure is chronic, it progresses to Permanent Threshold Shift (PTS) or Noise-Induced Hearing Loss (NIHL). **2. Analysis of Incorrect Options:** * **60 dB:** This is the intensity of a **normal conversation**. It is considered safe and does not cause fatigue or damage to the hair cells. * **70 dB:** This is the level of a vacuum cleaner or noisy office. While louder than a conversation, it is generally considered the "safe limit" for continuous 24-hour exposure without causing hearing impairment. * **140 dB:** This represents the **Threshold of Pain**. Exposure to this level (e.g., a jet engine or gunshot) causes immediate physical pain and can result in instantaneous, permanent acoustic trauma rather than simple fatigue. **3. High-Yield Clinical Pearls for NEET-PG:** * **The 3 dB Rule:** For every 3 dB increase in sound intensity, the energy doubles, and the "safe" exposure time is halved (e.g., 8 hours at 85 dB is equivalent to 4 hours at 88 dB). * **Notch Index:** Noise-induced hearing loss typically shows a characteristic "dip" or **notch at 4000 Hz (4 kHz)** on an audiogram. * **Attenuation Reflex:** The stapedius and tensor tympani muscles contract to protect the inner ear, but this reflex has a latency and is ineffective against sudden impulse noises (like explosions).

Q: Which of the following is NOT an occupational hazard for a dental surgeon?

Enteric fever. **Explanation:** The correct answer is **Enteric fever (B)**. Occupational hazards are risks faced by workers due to the nature of their work environment or specific job tasks. For dental surgeons, the primary occupational hazards are **biological** (via blood, saliva, and aerosols), **ergonomic** (musculoskeletal issues), and **chemical** (mercury, resins). **Why Enteric Fever is the correct answer:** Enteric fever (Typhoid) is transmitted via the **feco-oral route**, usually through contaminated food or water. It is not considered an occupational hazard for dentists because their clinical practice does not involve exposure to fecal matter or contaminated ingestion as a direct result of their professional duties. **Analysis of Incorrect Options:** * **AIDS (HIV) & Hepatitis B:** These are classic **blood-borne pathogens**. Dental surgeons are at high risk due to frequent use of sharp instruments (needlestick injuries) and potential mucosal contact with infected blood or saliva. Hepatitis B is, in fact, the most significant infectious risk for non-immunized dental staff. * **Herpes:** Dentists are specifically at risk for **Herpetic Whitlow**, a painful herpes simplex infection of the fingers, contracted through direct contact with a patient’s infected oral lesions or secretions without adequate glove protection. **High-Yield Clinical Pearls for NEET-PG:** * **Most common occupational hazard for dentists:** Musculoskeletal disorders (back/neck pain). * **Most common infectious hazard:** Hepatitis B (HBV is more transmissible than HIV in a clinical setting). * **Physical hazards:** Noise-induced hearing loss (high-speed drills) and ionizing radiation (X-rays). * **Chemical hazards:** Mercury poisoning (Minamata risk) and Silicosis (from dental laboratory sandblasting).

Q: Pneumoconiosis is most likely to occur with exposure to which particle size range?

0.5 - 3 125m. **Explanation** The development of pneumoconiosis depends primarily on the ability of inhaled dust particles to reach and settle in the gas-exchange regions of the lungs (alveoli). This is governed by the concept of **"Respirable Dust."** **1. Why Option A is Correct (0.5 – 3 µm):** Particles in the range of **0.5 to 3 microns (µm)** are of the ideal size to bypass the upper respiratory defenses and reach the alveoli. Once they settle in the alveoli, they are engulfed by macrophages, triggering an inflammatory response and subsequent fibrosis (pneumoconiosis). Particles smaller than 0.5 µm often remain suspended in the air and are exhaled, while those larger than 3 µm are usually trapped higher up in the respiratory tract. **2. Why Other Options are Incorrect:** * **Options B, C, and D (3 – 15 µm):** Particles larger than **5 µm** are generally too heavy to reach the lower respiratory tract. They are filtered out by the nasal hairs (vibrissae) or deposited on the ciliated epithelium of the trachea and bronchi via **impaction**. These are then cleared by the "mucociliary escalator" and swallowed or expectorated, preventing the deep lung tissue damage required for pneumoconiosis. **High-Yield Clinical Pearls for NEET-PG:** * **Respirable Dust:** Defined as particles < 5 µm in diameter. * **Most Dangerous Size:** While the range is 0.5–3 µm, many textbooks highlight **1 micron** as the most significant size for alveolar deposition. * **Silicosis:** The most common and progressive pneumoconiosis; characterized by "Egg-shell calcification" of hilar lymph nodes. * **Anthracosis:** Caused by coal dust; the mildest form of pneumoconiosis. * **Byssinosis:** Caused by cotton dust; characterized by "Monday Morning Fever."

Q: In factories, a welfare officer is appointed when the number of workers exceeds which threshold?

500. **Explanation:** The appointment of a Welfare Officer is a statutory requirement under **Section 49 of the Factories Act, 1948**. This act mandates that every factory employing **500 or more workers** must appoint a designated Welfare Officer to ensure the well-being, safety, and health of the employees. **Why Option B is Correct:** The threshold of **500 workers** is the legal benchmark established to ensure that larger workforces have a dedicated professional to mediate between management and labor, oversee canteen and crèche facilities, and ensure compliance with labor laws. **Analysis of Incorrect Options:** * **Option A (350):** This number does not correspond to any specific statutory requirement under the Factories Act. * **Option C (1000):** This is a common distractor. Under the Factories Act, a **Safety Officer** must be appointed when the number of workers exceeds **1,000** (or in smaller factories involving hazardous processes). * **Option D (5000):** This number is not a standard threshold for individual factory welfare or safety appointments in the context of the NEET-PG syllabus. **High-Yield Clinical Pearls for NEET-PG:** * **Crèche Facility:** Mandatory if more than **30 women** are employed. * **Canteen:** Mandatory if more than **250 workers** are employed. * **First Aid Box:** One box for every **150 workers**. * **Safety Officer:** Required if workers > **1,000**. * **Welfare Officer:** Required if workers > **500**. * **ESI Act (1948):** Applies to non-seasonal factories using power with >10 employees or non-power using with >20 employees.

Q: What is the employer's contribution to Employees State Insurance?

3.25%. ### Educational Explanation **1. Understanding the Correct Answer (A: 3.25%)** The Employees' State Insurance (ESI) Act of 1948 is a comprehensive social security scheme designed to provide medical care and cash benefits to employees in the organized sector. Effective from **July 1, 2019**, the Government of India significantly reduced the contribution rates to ease the financial burden on MSMEs and improve compliance. The current **Employer’s contribution is 3.25%** of the wages payable to an employee. **2. Analysis of Incorrect Options** * **B (3.5%) & C (3.75%):** These figures are incorrect. Prior to the 2019 amendment, the employer's contribution was significantly higher at **4.75%**. There has never been a statutory rate of 3.5% or 3.75% in the recent history of the ESI Act. * **D (3.2%):** This is a distractor. While it is numerically close to the correct figure, the ESI Act specifies the rate precisely at 3.25%. **3. High-Yield Clinical Pearls for NEET-PG** * **Current Rates (Post-2019):** Employer = 3.25%; Employee = 0.75%; Total = 4.0%. * **Wage Ceiling:** The current wage limit for coverage under ESI is **₹21,000 per month** (₹25,000 for persons with disabilities). * **Exemption:** Employees earning less than **₹176 per day** (daily average wage) are exempt from paying their share (0.75%), though the employer must still pay their 3.25%. * **Benefits:** ESI provides six benefits: Medical, Sickness, Maternity, Disablement, Dependents', and Funeral expenses. * **Funding:** The State Government contributes **1/8th (12.5%)** of the total cost of medical care, while the ESI Corporation bears the remaining 7/8th.

Q: What is the HIV seroconversion ratio after a needle-stick injury?

Less than 3 in 1000. **Explanation:** The risk of HIV transmission following a percutaneous exposure (needle-stick injury) is relatively low compared to other blood-borne pathogens. According to the CDC and standard occupational health guidelines, the average risk of HIV seroconversion after a single needle-stick injury involving HIV-infected blood is approximately **0.3%**. 1. **Why Option C is Correct:** 0.3% mathematically translates to **3 in 1,000**. Therefore, the risk is accurately described as "less than 3 in 1,000" (or roughly 1 in 333). This figure represents the baseline risk before the administration of Post-Exposure Prophylaxis (PEP). 2. **Why Other Options are Incorrect:** * **Option A (<1 in 3000):** This underestimates the risk significantly (0.03%). This level of risk is more characteristic of mucous membrane exposure (0.09%). * **Option B (<1 in 300):** While 1 in 300 is approximately 0.33%, the standard epidemiological benchmark used in exams is the "Rule of 3," making Option C the more precise technical choice. * **Option D (<3 in 100):** This represents a 3% risk, which is ten times higher than the actual risk for HIV. However, 3% is the approximate risk for **Hepatitis C (HCV)** transmission. **High-Yield Clinical Pearls for NEET-PG:** * **The Rule of 3s (Risk of transmission after needle-stick):** * **Hepatitis B (HBV):** ~30% (Highest risk, especially if HBeAg positive). * **Hepatitis C (HCV):** ~3%. * **HIV:** ~0.3%. * **Mucous Membrane Exposure:** The risk for HIV is even lower, approximately **0.09%**. * **PEP Timing:** Post-Exposure Prophylaxis for HIV should ideally be started within **2 hours**, but can be initiated up to **72 hours** post-exposure. The standard duration is **28 days**.

Question 1

Which of the following statements about N95 masks is true?

Accepted Answer

A beard does not allow for a proper seal and makes the N95 ineffective.

Answer

They were designed for influenza viruses during the H1N1 outbreak.

Answer

N- stands for National Institute of Occupational Safety and Health.

Answer

It filters 95% of all particles smaller than 0.3 micrometers.

Question 2

The decibel level above which auditory fatigue occurs is:

Accepted Answer

85 dB

Answer

60 dB

Answer

70 dB

Answer

140 dB

Question 3

Which of the following statements is true regarding the Rajiv Gandhi Shramik Kalyan Yojana scheme of ESI?

Accepted Answer

Beneficiaries of this scheme are insured people rendered involuntarily unemployed.

Answer

Beneficiaries are insured people rendered voluntarily unemployed.

Answer

This scheme does not provide medical care for beneficiaries and their family members.

Answer

Beneficiaries are insured pregnant women with other illnesses.

Question 4

Which of the following is NOT an occupational hazard for a dental surgeon?

Accepted Answer

Enteric fever

Answer

AIDS

Answer

Hepatitis B

Answer

Herpes

Question 5

Pneumoconiosis is most likely to occur with exposure to which particle size range?

Accepted Answer

0.5 - 3 125m

Answer

3-5 125m

Answer

5-10 125m

Answer

10-15 125m

Question 6

Which of the following is excluded from the extended Employees' State Insurance (ESI) benefit?

Accepted Answer

Small power employing 10 to 18 people

Answer

Newspaper establishments

Answer

Non-power employing less than 18 people

Answer

Non-power employing 18 or more people

Question 7

In factories, a welfare officer is appointed when the number of workers exceeds which threshold?

Accepted Answer

500

Answer

350

Answer

1000

Answer

5000

Question 8

What is the employer's contribution to Employees State Insurance?

Accepted Answer

3.25%

Answer

3.5%

Answer

3.75%

Answer

3.2%

Question 9

What is the HIV seroconversion ratio after a needle-stick injury?

Accepted Answer

Less than 3 in 1000

Answer

Less than 1 in 3000

Answer

Less than 1 in 300

Answer

Less than 3 in 100

Question 10

A person working in a high-temperature environment should increase their intake of which of the following?

Accepted Answer

Sodium chloride (NaCl)

Answer

Iron

Answer

Vitamin D

Answer

Phosphates

Occupational Health — MCQs

Occupational Health — MCQs

On this page

Practice by Chapter

Want unlimited practice?