Singaporeans are working harder than ever before - up to 10 hours more per week - said a recent survey. With more time spent in the office, here are some of the health hazards you should be watching out for.

Hazard #1: Sitting too long

Hazard #2: Eating at your desk

Hazard #3: Breathing bad air

Hazard #4: Having a cluttered desk

Hazard #5: Your boss

1. Sitting too long in a badly designed chair

[Above: Proper way of sitting at the office]

A poorly designed chair will not support your back well and can provoke both acute and chronic back pain, reported Newsweek online. To ensure optimal ergonomics at work, your lower and mid-back should be well-supported.

Avoid slouching or leaning foward, especially when you are tired from sitting for long periods, said the Denver Post.

A good way to prevent back problems is to take a short break after 20 to 30 minutes of sitting. Stand up for about 30 seconds or take a short walk around the office and stretch your muscles as needed.

Adjust your chair such that arms are flexed at 75 to 90-degree angle at the elbows. Knees should be aligned with the hips, or slightly higher, while sitting in the office chair, said spine-health.com.

2. Eating at your desk

Multi-tasking - dealing with e-mails and phone calls - while eating your lunch can distract you and may cause you to overeat and reach for that extra doughnut or sugar-laden cake even though you're not hungry, said Newsweek.

Worse, half of all people do not wash their desks before they eat, said dietitian Elisa Zied in a CBS interview.

"There's 400 times the amount of bacteria on your desk than there is on your office toilet," she says, emphasising the need to disinfect. She recommends giving the office table a good wipe down daily.

If you really have to eat at your desk, make sure that your food does not touch the surface of the table. If you are holding onto a sandwich or a curry puff, make sure to rest it on a large napkin or plate.

3. Breathing bad air

While your deskmate's body odour may be a cause for protest, there is more evil lurking around in the office air.

Award-winning toxicologist Professor Chow Sek Chuen said poor building infrastructure is a culprit for poor air quality.

When buildings are not well waterproofed, the water from leaking rooftop pipes or air-con cooling system can seep through the walls. The dampness then passes through to the other side of the wall, creating airborne mold spores, he said.

Inhaling mold spores can exacerbate allergic reaction, said Dr Chow.

To prevent such problems, it is important for a building to be well ventilated. "Ventilation is very important. It helps to dry the room and bring in fresh air," he says.

4. Having a cluttered desk

If you have papers that are piled up so high around you and under your table such that you have difficulty even finding a place to sit or do proper work, it might be a good idea to start cleaning your workplace.

A cluttered desk may lead to disorganisation, a bad impression on your colleagues and a similarly messy mind, said sixwise.com.

Disorganised people do not realise how much time they have wasted trying to find things, reported the New York Times (NYT). And when things cannot be found, they procrastinate further, which lowers their productivity, continued the report.

To organise your desk better, set aside a few hours - outside of regular office time - to clear the mess.

Start with a simple filing system with a multi-folder file and label each section with general tabs like "meetings" or "ideas".

Keep the files that you will use most often near you and those that are used less often in your drawer, said NYT.

5. Your Boss

Bullying in the workplace is surprisingly common, said NYT. Instead of physical bullying, office bullies practise subtle tactics.

It may start with with a belittling comment at a staff meeting. Later it becomes gossip to co-workers and forgetting to invite someone to an important work event, continued the report.

If the bully is a supervisor, victims may be stripped of critical duties, then accused of not doing their job, Gary Namie, founder of the Workplace Bullying Institute, told the NYT.

Researchers at the University of Manitoba in Canada have found that the emotional stress from being bullied at work is more severe than that of sexual harassment.

A good strategy for fighting off the office bully would be to alert your superiors. If you can join forces with other affected colleagues and complain as a group, you're twice as likely to succeed, said Newsweek online.

However, if it doesn't work and if the bad moments outnumber the good, the best health choice may be to start working on your resume, added the report.