Compared to many other outdoor activities, scuba diving is generally considered a low-risk activity. However, it does involve some trauma or illness, such as sunburn, pulmonary embolism,  Oxygen Toxicity，nitrogen narcosis, even be attacked by unknown sea creatures.

So, is scuba diving safe?

The answer is yes, when properly trained, using safe diving practices in conditions appropriate for that training, scuba diving is indeed a very safe activity.

To put the level of risk into perspective, a 2010 workshop conducted by the Diver’s Alert Network (DAN) showed that in the USA, annual fatality rates associated with scuba diving averaged 16.4 deaths per 100,000 divers – a figure similar to those associated with driving a vehicle (16 per 100,000 people), and only marginally more than the average number of deaths that occur while jogging (13 per 100,000 people)

Of course, the following measures are what a diver especially a novice needs to do before diving for avoiding accidents happened.

1. Do a Fully Health Check

Almost all diving training institutions or clubs require novice divers to complete a mandatory medical questionnaire before taking a scuba diving course. Some countries even require divers to obtain a doctor's clearance before starting.

It is widely believed that the main cause of death in scuba divers is an existing medical condition, primarily some of cardiovascular diseases, such as high blood pressure (hypertension) which is often overlooked on the water surface, but can be fatal underwater.

It is rare that diving accidents are caused by medical problems, but all divers must be serious to their health. You may not need to be a professional diver or athlete, but if you have an existing medical condition, you still must go to a regular hospital and seek medical clearance from a doctor to dive.

2. Check your Gears

To keep your life safety underwater, it largely depends on your underwater gears. Don't be lazy to check your devices before diving. It could create a life-threatening situation for both of you if some of the gears are malfunction.

Moreover, most of the equipment-related accidents are not caused by broken equipment, but because divers aren't sure how it works. 

Therefore, it is necessary to take courses on how to use underwater gears.

Generally, there is no "unsafe" diving gears as long as they properly maintained or used, and you are well instructed in its operation.

Before scuba diving, we will do a pre-check to for the following gears.

1. The oxygen tank: make sure we have enough air in our tank.
2. The wearing jackets:the jacket we wear which can control our buoyancy underwater and stay afloat runs normally.
3. Defoggers: we can see underwater clearly with the defoggers which can recuse the risks from coral reef or unknown creature.

3. Do not drink alcohol or take drugs before diving

Remember that it is not advisable to drink alcohol before or after diving.

The dangers of drinking alcohol on diving are self-evident.

Firstly, alcohol can have a great effect on divers’ judgment, resilience and body coordination, because alcohol will depress the central nervous system. However, those affected divers are often unaware of the damage.

Dr. Glen Egstrom, a diving physiology researcher at the University of California, Los Angeles, reviewed more than 150 studies exploring the effects of alcohol on athletic performance and found that alcohol is associated with about 50 percent of diving accidents that occur in people of drinking age.

Secondly, alcohol causes the blood vessels in our skin to dilate, which in turn increases blood flow to the skin, ultimately making us more prone to hypothermia.

Thirdly, drinking alcohol can also affect our blood pressure, as those blood vessels supplying our muscles constrict as blood alcohol levels rise. This is especially dangerous for divers who are already at risk for heart disease.

4. Know your limits

Be sure to dive within your own limits. The limits of human be change every day and every year. You might be eligible to dive to 100 feet years ago, jumping straight into that deep dive might not be the best plan but if you haven't dived in a few years

Exceeding training limits is a significant cause of scuba diving accidents. Having an entry-level diving certification doesn't mean you can take on some remote pinnacles and rough currents.

5. Never diving without a buddy

Although the overall mortality rate for diving is very low, did you know that? Some data have pointed out that 86% of the accidental deaths of divers are due to them going alone.

Not only does a buddy system greatly reduce the risk of accidents and fatalities in scuba diving, it is also more fun than diving alone. When you are unwell or encounter an ocean current, your companions may be able to save you in distress.

What’s more, as a communal sport, half of the fun for scuba divers is sharing the experience with each other.

6. Be familiar with the underwater areas

When diving in a new underwater area, you must make a more comprehensive investigation and assessment of the surrounding and seabed conditions, even if you are experienced in diving.

Except the diving environment, you’d better keep an eye on weather conditions, water temperature, water depth, even whether there is a reef or dangerous biological attack which may be threaten your life. 

Further more, be aware of local tides and currents.

Last but not least: plan your dives in advance: such as preparing necessary first aid medicine, planing the travel route and days, the list of accompanying persons and diving proficiency,  necessary pre-diving training.

Whatever, it is a must for every diver to obey the rules set by experienced divers and putting safety first.

Happy Starting, happy ending.