Your office AC making you sick? Doctors reveal the warning signs of poor indoor air quality

You check the Air Quality Index before stepping outside. But what about the air you breathe for eight to 10 hours every day inside your office?

As more Indians spend most of their working hours in air-conditioned offices, health experts are warning that indoor air quality remains one of the most overlooked threats to respiratory health. While many people associate office air conditioning with temporary discomfort such as dry eyes or a scratchy throat, doctors say the consequences can be far more significant.

According to the U.S. Environmental Protection Agency (EPA), concentrations of some indoor pollutants can be two to five times higher than typical outdoor levels.

“People are very aware of outdoor pollution, but urban professionals spend nearly 90% of their day indoors, whether in offices, homes, cars or malls. Indoor air quality remains an under-discussed health issue,” said Dr Karthik Madesh Ratnavelu, Director and Senior Consultant, ENT, Head and Neck Surgery and Director and Head, Advanced Institute for Sleep Health, SIMS Hospital, Chennai.

WHY YOUR OFFICE ENVIRONMENT MAY BE AFFECTING YOUR HEALTH

According to Dr Ratnavelu, the problem is often not air-conditioning itself but the quality of the air circulating through indoor spaces.

Poor indoor air quality can arise from low humidity, inadequate fresh air exchange, accumulation of dust, mould growth and allergens trapped within indoor circulation systems. Over time, this can trigger symptoms that many employees fail to associate with their workplace.

These symptoms may include:

• Recurrent throat clearing
• Chronic dry cough
• Frequent headaches
• Nasal congestion and blockage
• Worsening sinus symptoms
• Vocal fatigue
• Breathing discomfort
• Poor sleep quality

“A cool room is not always a healthy room. Clean air deserves as much attention as comfortable temperatures,” Dr Ratnavelu said.

THE BIGGEST CLUE YOUR OFFICE MAY BE TO BLAME

One of the easiest ways to identify whether symptoms are linked to the workplace is to observe patterns.

Doctors say symptoms related to indoor environmental exposure often worsen during office hours and improve once a person leaves the workplace.

“The biggest clue is recognising a pattern. If symptoms predictably get worse during office hours and improve once you get home or during weekends, it suggests that environmental factors may be playing a role,” Dr Ratnavelu explained.

Dr Benhur Joel Shadrach, Senior Consultant, Pulmonology, Interventions and Sleep Medicine, Rela Hospital, Chennai, said he frequently sees such cases in clinical practice.

“There is a direct relationship between exposure and the development of symptoms. When people spend eight to 10 hours in a closed environment, symptoms begin after exposure and substantially improve when they are away from the workplace during weekends or holidays,” he said.

5 SIGNS YOUR OFFICE AIR AFFECTING YOUR HEALTH

Experts say the following warning signs may indicate that workplace air quality is contributing to your symptoms:

• Symptoms worsen during office hours
• Symptoms improve during weekends or holidays
• Persistent dry throat or throat irritation
• Frequent headaches at work
• Breathing discomfort indoors

HOW INDOOR AIR CAN AFFECT YOUR LUNGS

Experts say prolonged exposure to dry, poorly circulated indoor air can affect both the upper and lower respiratory tract.

In the upper airways, individuals may experience dryness, congestion and reduced mucociliary clearance – the body's natural mechanism that traps and removes dust, bacteria and viruses. When this protective system becomes less effective, irritants and microbes can accumulate more easily.

The lower respiratory tract may also be affected.

Dr Shadrach noted that prolonged exposure to dry and cold indoor air can trigger bronchospasm, a condition that causes chest tightness and breathing difficulty. For people with asthma, allergic rhinitis, sinusitis or chronic respiratory diseases, symptoms can worsen significantly.

In rare cases, poorly maintained cooling systems have also been associated with severe infections such as Legionnaires' disease, a form of pneumonia linked to contaminated water systems.

WHO IS MOST VULNERABLE?

People with pre-existing respiratory conditions appear to be at greater risk.

These include individuals with:

• Asthma
• Allergic rhinitis
• Sinusitis
• Allergic rhinosinusitis
• Chronic bronchitis
• Sleep-related breathing disorders

However, experts caution that even otherwise healthy individuals can develop symptoms when exposed to poor indoor air quality for prolonged periods.

Doctors often investigate workplace-related symptoms by examining medical history, identifying symptom patterns, evaluating workplace conditions and determining whether multiple employees are experiencing similar complaints.

“If several employees develop similar symptoms, that becomes a stronger clue that there may be an environmental issue within the workplace,” Dr Ratnavelu said.

WHY INDOOR AIR QUALITY IS STILL UNDERESTIMATED

While public discussions often focus on vehicle emissions and outdoor pollution, experts say indoor environmental triggers receive far less attention.

Modern office spaces frequently rely on sealed environments with limited natural ventilation.

Poor ventilation can also allow carbon dioxide (CO2) levels to build up indoors. While CO2 itself is not usually harmful at levels found in offices, elevated concentrations can indicate inadequate fresh air circulation and have been associated with symptoms such as headaches, fatigue, drowsiness and reduced concentration.

In addition to dust and allergens, indoor spaces may contain fungal growth from damp areas, particulate matter, volatile organic compounds released from furniture, adhesives and cleaning products, and other invisible pollutants.

“Recent studies show that indoor exposures, including office environments, are contributing to respiratory symptoms. Many of these pollutants are not visible to the naked eye, making them easy to overlook,” Dr Shadrach said.

The challenge, doctors say, is that symptoms often develop gradually.

What begins as mild throat irritation or occasional headaches can slowly progress to persistent fatigue, poor sleep, allergies and chronic cough, leading many people to normalise the symptoms rather than investigate the cause.

WHAT CAN OFFICE WORKERS DO?

Experts recommend several simple measures to reduce the impact of prolonged exposure to air-conditioned indoor environments:

• Stay adequately hydrated throughout the day
• Avoid sitting directly under strong air-conditioning vents
• Take regular breaks in areas with fresh air and natural ventilation
• Consider saline nasal sprays or rinses if prone to dryness or allergies
• Do not ignore recurring cough, throat irritation or breathing difficulties

Dr Shadrach also recommends maintaining indoor temperatures between 24°C and 27°C and humidity levels around 40–50%.

WHAT EMPLOYERS SHOULD DO

Workplace health is not only about ergonomic chairs and standing desks, experts say.

Regular servicing of HVAC systems, timely filter replacement, monitoring humidity levels, ensuring adequate fresh air exchange and preventing mould growth are essential measures for maintaining healthy indoor environments.

Employers should also minimise exposure to strong fragrances and highly irritating cleaning chemicals, which can further aggravate respiratory symptoms.

While outdoor pollution continues to dominate public discussion, doctors say the air inside offices deserves equal attention. For millions of professionals spending most of their waking hours indoors, the quality of workplace air may be influencing their health far more than they realise.