Compared to the world’s most dangerous jobs (commercial fishing, logging, flying aircraft), professional computer users tend to think they’re fairly safe at their workplace. But even the most sedentary job has its risks. Here are a couple of health concerns you might encounter if you sit at your computer for long hours – plus suggestions for preventing or treating them.

Carpal tunnel syndrome. Any repetitive motion, no matter how small, can put stress on joints, muscles, tendons and ligaments. Carpal tunnel syndrome is the painful inflammation of the tendons that run from the hand through the wrist and lower arm. It’s caused by repeated stress from movements such as typing and mousing.

To avoid carpal tunnel syndrome, be sure to use ergonomic keyboards and mice, which place the hands and wrists in the optimum positions for natural movement. Take frequent breaks and keep up your overall fitness. And try to avoid stress – that interoffice tension will manifest itself in your shoulders, neck and arms more than anywhere else.

Laptop heat rash. As the name implies, laptops are designed to be used on your lap. But as the machine generates heat (some laptops may reach more than 186 degrees F internally), the vents that circulate air to cool it off are blocked by your pliable, fabric-covered thighs. If you’re smart enough to move your computer before you receive first-degree burns, you still may be dismayed to find an unsightly rash called erythema ab igne under your jeans.

Though the rash isn’t dangerous, if your lap’s getting hot enough to cause a rash, you should be concerned with fertility issues if you’re male. Just as wearing too-snug underwear can cause genital temperature to rise, which negatively affects sperm count and mobility, using a laptop on your lap has been shown to increase genital temperature to well above the sperm safe level.