The two associations that represent security firms say they frown on clients that spell out age limits on guards in their contracts.
But they add that there is little they can do besides educating these clients not to reject older guards.
"As long as a person is able-bodied and passes the medical examination, there should not be an age limit for guards," said Mr T. Mogan, president of the Security Association of Singapore, which represents about 150 security firms.
Mr Robert Wiener, president of the Association of Certified Security Agencies, representing about 70 security firms, added: "If I see a contract like that, I will report it to the union."
He also encourages his association members to report examples of age discrimination to the authorities.
The fair employment watchdog, the Tripartite Alliance for Fair Employment Practices, said that one in five of the 303 complaints that it received last year was related to age discrimination.
Mr Nazarisham Mohd Isa, director of Jasa Investigation and Security Services, said that some clients prefer younger guards for their youthful image.
"We just have to try to persuade them that older guards are just as good," he said.
Mr Richard Ow, 66, is employed by security firm Soverus and has kept watch at the Robertson 100 condo for nine years.
He said he is not discouraged by talk that older guards are less effective than younger ones, adding: "I may not be young, but I am just as alert and committed to the job."
His condo manager Anuar Ahmad agreed: "Older guards have a better temperament, are more patient and they think before they act, which makes them suitable for condo security jobs.
"It will be a pity if they cannot continue to work just because there are people who don't want them."
The government agencies, whose oversight led to the stipulation of age limits for security guards in their contracts, said they do have older guards within their ranks.
The oldest guard at the Ministry of the Environment and Water Resources is 58-year-old Mohamed Shariff Abdullah, who conducts patrols and hands out visitor passes at the ministry.
The Ministry of Foreign Affairs said that about 30 per cent of its guards are older than 60, while the Civil Aviation Authority of Singapore said that half of the guards at the Singapore Aviation Academy are above 45 - the maximum age it stipulated in its tender document.
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