That said, I do not believe that ticketing irresponsible dog owners as suggested by your correspondent addresses the problem. As he says, we 'impose bans on smoking and curb littering by having on-the-spot fines'. How often do people who commit these offences get a ticket? If fines were handed out to irresponsible dog owners this would necessitate having highly trained police officers standing in parks to catch these people.

This is a classic example of a waste of human resources. I am not saying that owners should be allowed to continue with their selfish acts but that we need to come up with more effective measures.

Many countries have designated dog parks. In Canada, these parks are well equipped with special disposal bins, and doggy bags are available.

They act as visible reminders to owners that they have a responsibility not only to their dogs, but to others in the vicinity. Another possible solution is to have designated parks that allow animals.

Popular parks and tourist attractions such as Victoria Park and The Peak can continue to bar pets, but in the designated parks pets will be allowed.

This is a win-win situation, as the public would no longer run the risk of stepping on the mess left by canines, and dog owners could enjoy special facilities tailored to their pets.

Ho Kam-tong, Yuen Long

Passengers right to be concerned

I refer to the incident last month involving a Cathay Pacific Boeing 747 that was supposed to fly to Frankfurt on December 19 ('Passengers delayed as engine on Cathay jumbo malfunctions', December 21).

You report how a passenger 'described hearing a loud bang from the engine and saw a large, brief flash'.

A Cathay spokeswoman confirmed that the number two engine on flight 289 developed a problem but denied there had been an explosion. She would not say what the engine fault was.

The father of the passenger who was quoted was angry that the airline denied an explosion. It was a loud bang that all passengers could hear.

Given what the passengers heard, why did the company refuse to explain the engine fault? I think it has let down its passengers.

There was another incident involving the airline in November.

Cathay flight 270 (from Amsterdam to Hong Kong) had a problem with the pressurisation system 'causing the cabin to lose air pressure' ('Relief at safe return after forced landing', December 1). This happened at cruiser altitude (which I would calculate to be 35,000 feet). At that altitude, people have nine seconds to get on their oxygen masks. The Cathay spokesman said the incident was very rare.

When it comes to the reliability of Cathay's aircraft, I feel there is a great deal of room for improvement. After all, not too many people have the opportunity to travel by private jet instead of using commercial airlines like Cathay.

Eugene Li, Deep Water Bay

Trial drug scheme failed

The government hoped that the voluntary drug-testing trial in Tai Po secondary schools would help develop an anti-drug culture. This has not happened and now some people have called for mandatory testing.

Although compulsory tests may be more effective than a voluntary scheme, it could strain relations between schools and parents. Some parents who suspect their children are using drugs might resist a compulsory test because they want to protect their son or daughter.

Students expect teachers to help them, but teachers would face conflicting roles with these drug tests. At the moment, they can sometimes become like a social worker, but with a mandatory scheme they would become almost like the police.

The trial scheme in Tai Po should not have been set up in the first place. It has not helped to establish an anti-drug culture.

Li Kai-ching, To Kwa Wan

Hair tests act as a deterrent

It is worth going ahead with hair testing for drugs in schools despite the expense.

We can more effectively find those students who are drug abusers with these tests.

The earlier we identify students who are taking illicit drugs, the sooner they can get help. Ketamine and cocaine can cause permanent damage. The hair test can show if someone has taken drugs in the past three months so it can act as a deterrent.

While I think it can be effective, it cannot solve the problem of drug abuse in Hong Kong. The government must continue to support Christian Zheng Sheng College and other non-governmental organisations.

Zheng Sheng College has shown that it is able to help teenagers with a drug problem get back on the right track so that they can make a contribution to society.

While I accept that the hair tests will require a substantial financial investment, it is money well spent.

Chris Ho Ka-kui, Lam Tin

Helpers' claims unfounded

I have often heard the argument that overseas domestic helpers claim they are contributing towards the Hong Kong economy.

However, I think the contribution they make is to the economy of their own countries.

They should not forget that they have been earning money in Hong Kong and sending it home, so it is their country that benefits. However, they do serve Hong Kong families and we should thank them for that.

Gary Ahuja, Tsim Sha Tsui

Quiet Sunday ruined by noise

Once again the quiet of a tranquil Sunday afternoon in Happy Valley was rudely broken by the most intrusive and obnoxious noise.

This time it consisted of almost an hour of Cantonese chatter over a loudspeaker that literally shrieked and echoed all over the valley.

Why is it that the Leisure and Cultural Services Department and the Environmental Protection Department allow such annoying and noisy events on a regular basis?

Surely they are illegal under the Noise Control Ordinance.

Happy Valley residents have endured Cantonese opera in the open air, concerts, dance and puppet troupes with loud music, and rehearsals for all the above.

The audio 'entertainment' is amplified by huge speakers and a sound system appropriate for a small stadium.

Such things usually occur on Saturday afternoon or Sunday, the only times when the nearly incessant renovation noise from nearby flats is prohibited.

Even more amazing is the fact that the Environmental Protection Department has taken action against a school on Lantau because of one complaint from a neighbour about the noise of children playing.

Despite dozens of complaints (according to the police) from Happy Valley residents, the outdoor noise-making events continue in the infield area of Happy Valley racecourse.

These two government departments need to take a consistent approach to noise issues and tackle the greater nuisances rather than minor ones.

William Meacham, Happy Valley

We all have vital role to play

The problem of global warming is getting worse.

Humans, including Hong Kong citizens, keep producing large amounts of greenhouse gases.

However, there are simple things we could all do to reduce our carbon footprint.

For example, in our own homes we can simply turn off electrical appliances when we are not using them.

The government has passed legislation aimed at controlling carbon emissions, but that is not enough.

All citizens need to develop the correct mindset which embraces the concept of following a green lifestyle.

It is not uncommon to see electricity being wasted in some public areas. You can walk along a road which gets very few vehicles at night and yet the street lights are still switched on.

The government has an important role to play.

It can set examples for the public to follow. If people see that the government is determined to adopt a green approach, they will follow suit.

Kwong Shu-chung, Ho Man Tin

Far removed from masses

The most recent story of the further descent into Maoism of Bo Xilai, the Chongqing party boss, suggests that he has an extremely opportunistic personality ('Drama off the air as 'red' TV takes over', January 4).

Given that he sent his own son to be schooled in Harrow and then on to Oxford University, clearly demonstrating his preference that his own flesh and blood should not be educated in China's communist system, he really displays an astoundingly blatant hypocrisy.

He is not alone, of course, among the class of politicians that exhorts 'the masses' to live and behave in ways they never would dream of doing so themselves. He is undoubtedly an excellent example of how very distant from the masses many, if not all, top leaders on the mainland have become, however populist they may attempt to be.

J. Fearon-Jones, Macau