QRA Test Chambers to Perform Stress Screening Tests

 

TS 120 Chamber - up to 15 C / min change rate uncontrolled 

Presenting QRA range of test chambers and test services to our multinational clients worldwide for stress screening tests (SST), The above TS 120 chamber can perform change rates of approximately 15 C / min between the temperature ranges of 

a) -    40 C Cold 

    + 125 C Hot

b) - 55 C Cold

   + 150 C Hot

c) - 65 C Cold 

   + 150 C Hot

according to MIL STD 883 D 1010.7 Conditions D, E,F and H (US). Jedec  (Japan)  A 104 conditions for 2 zone thermal chambers. 

Test Duration per cycle : 32 minutes

Test Cycles                   : 1000 hours (41.67 days)

ESS chamber - up to 5 C / min controlled. 

The above chamber (ETSP TH 216 S) can perform Temperature Cycle Tests for up to 1000 hours or 41. 67 days.

Temp Change Rate : 0.5 up to 5 C / min

Cold Zone :  - 20 C

Hot Zone  : + 150 C

RH          :  20 to 95% 

We offer the following packages :

a) New Chambers Sales (with warranty 1 year on site)

b) Rental Chamber (minimum duration 3 months)

c) Test Services 

For more information, contact :

Website : www.qra.com.sg

Email    : mark@qra.com.sg

               qrasales@qra.com.sg

What is Stress Screening Test (SST) ? Why Manufacturers MUST perform SST ?

 

                                           Battub Curve comparing Failure (Death) Rate against Time.  

The above picture is a typical 'bathtub curve'. The graph originates from the Life Insurance Industry which plots the life of people IN GENERAL. The curve curve can be dissected into 3 stages of life. 

1st stage : Birth (infant) to Toddler (5 years old).

2nd stage : 5 years to say 75 years of age. 

3rd stage : 75 years of age to end of life (for example) 90 years. 

1st stage,  irregardless of the country's developed status and wealth, infants and very young chidren DO NOT have the antibodies, and basic  health immunity built in them to withstand bacteria, viruses and the like. Hence, there is always a much  higher chance of them falling sick, contracting simple illnesses (since their body immunity takes several years to develop).Infants until about 2 years of age, have no cognitive awareness of themselves, and hence can't effectively communicate and receive communication - hence, they will do as they like and crawl on the floor, and through natural curiosity, pick up things on the floor, feel, smell and eat things. Hence, the incidence of hand foot and mouth disease is prevalent worldwide. 

As a result, the infant mortality rate is HIGH for the first 5 years.

2nd stage Roughly around 5 years of age, their cognitive awareness is developed, about themselves, their surroundings and taking care of their hygiene. Additionally, by nature, their bodies would have decent immunity and strength to ward off the basic virus and bacteria borne diseases. 

Of course having a strong health care support system in the country is very important too.

From 5 years of age till 75 years, it has been observed (through clinical studies tracking people from cradle to grave, there are countless reports out there) that the incidence of death, while it happens, is relatively small in comparison to the first stage. People would have developed body immunity as well as the support systems for them to seek urgent medical help if and when the health issues arise. The chances of death is relatively low compared to 1st stage. 

Incidents like road accidents, Tsumanis, COVID, and SARS are black swan events but the death rate barely hit 1 % of any population. 

3rd stage Approaching end of life (this is rather wide, from country to country, ranging from 76 in the US to 85 in Singapore and Japan), people are generally weaker and health issues will crop up more frequently and over several months and years before the end of life 

                                                                     Sports Watch 

Typical Notebook. 

So it is exactly the same curve which is applicable with consumer and industrial products. Sports watches, handphones, notebooks, IPads, cars and other stuff which practically everybody has and uses. Cars, buses, boats, planes and military equipment all exhibit the same behavior.

It is called the Product Life Cycle. It typcially falls into 3 segments as shown above too.  

So coming to the 6 million dollar question. I have been rather long winded but I need to explain the objective of this post.

1. What is a Stress Screening Test ?

2. Why Manufacturers MUST perform SST ? 

                                                 Typical Stress Screen 1 Cycle 

What is a Stress Screen Test ? 

A stress screen test is a test typically devised by QA engineers or managers of a manufacturer to ensure that the products made are robust. Typically this is done by utilizing environmental chambers and  controlling the following parameters below. The objective is to weed out infant mortalities from the products made in the assembly line. Hopefully, the infant mortalities only account for less than 5% of the total production run (hence yield or success rate is 95%). 

a) Temperature setpoints - high and low temperature settings

b) Dwell Times - ranging from a few minutes to a few hours.

b) Temperature Change Rates - from 1 to 5 deg C per minute are very common. 

c) Number of cycles - minimum of 4 days (96 hours) to 1000 hours (41.6 days). 

The Temperature Setpoints are devised by choosing temperatures which are higher and lower than what the product (for example the 2 shown above) would be subjected to, worldwide.

What Temperature Range would the 2 products be subjected to ?

Sportswatch :  - 20 C (cold winter runs) to say 50 C (desert run)

Notebook  :   10 C to 38 C (normally used indoors so the range is much smaller than sports watch).

What Temperature setpoint should I set for the 2 products to produce an effective Stress Screen ?

1 :  - 30 C to 60 C 

Notebook  :   0 to 45 C 

What Temperature Change Rates should I set ? 

1 to 5 C / minute is most ndustries standard though there are some military grade products requiring 15 C to 20 C / min. 

Dwell Time ?

30 minutes up to 4 hours each zone.  

Number of Cycles ?

For it to be effective, the more cycles the better. 

So 500 to 1000 hours is recommended

Why Manufacturers MUST perform SST tests ?

If the products are shipped out without the SST tests, if say even 5 % fail in the field, the brand name of the manufacturer is adversely affected. 

There have been incidents of complete recalls of car batches in EV and ICE cars in the past, This is due to major glitches in the products design and reliability hence the total recall which easily costs hundreds of millions of dollars in expenses.

Do you want to risk your company / product brand name ? 

The decision is a simple one.

Speak to the experts ; At QRA, we can assist you !

Website : www.qra.com.sg

Email    : mark@qra.com.sg

               qrasales@qra.com.sg 

  

 

QRA's role in eliminating denger fever in Singapore

The Temperature Cyle proposed by QRA to Stress Screen the Polyethelyne Containers through numerous rounds of Heat and Cold Stressing to induce failure in the container. 

   Last year, QRA was approached by a huge MNC whose Social Enterprise arm was tasked to find ways and means to eradicate the dengue fever menace caused by Aedes mosquitoes in Singapore. Now Singapore is a tropical country, and our climate is very humid. We can record, easily 100 - 120 days of rain per year, so there are instances of water ponding and places where these mosquitoes can breed. 

Aedes is one such specie of mosquito and dengue fever can be deadly. Every year, scores of people, will get infected, and some may die from this disease which is characterised by intermittent high fever, chills, some rashes on the body and the person infected must be hospitalised immediately. 

The chamber providing the Temperature Cycling Test - ETSP Temperature Cycle Chamber (S.Korea) 

The MNC's social enterprise arm partnered with our National Environment Agency (NEA) for this project called Project Wolbachia. You see Wolbachia mosquitoes are another specie of mosquitoes, which are harmless and do not posess nor carry the dangerous dengue strain in their bodies.  Hence the objective of Project Wolbachia is to breed enough Wolbachia in the Labs at the MNC and later release them into the open air and allow them to a) fly around and b) breed with the Aedes mosquitoes.

The offspring of this new specie, will then be rendered harmless and behave like any mosquito The offspring is hopefully not able to transmit any dengue fever virus. When the Wolbachia mosquitos are bred in the Labs, they are then kept in refrigerated glass tanks at - 17 C. 

Multiple Level Polyethelene Containers - each level housing mosquitoes.

After enough of them are bred and raised, they will then be shepherded into containers such as the above. Each container contains 30 segments and each segment housing some 100 mosquitos (my guess). The execution of the project is high tech, like in some James Bond movie. These containers which are made of Polyethelene, will be mounted in refrigerated vans and these vans will ply a certain route through all the housing estates in Singapore.

At certain junctions or roads, the GPS will trigger the opening on the side of these vans automatically and one segment of the red container (there are 30 segments in total housed in a clear plastic cover) will be released and the Wolbachia mosquitoes will fly out and do their thing. 

The concern for the MNC was this :

The van is refrigerated and the mosquitoes are kept in the freezer at -17 C. Once they reach the designated location for release, the sliding door will automatically open and 35 - 38 C air will rush in. 

Hence after repeated drive bys, the containers will be experiencing a Temperatue Cycle of roughly 

- 17 C to + 35 C in a few minutes.

Over repeated locations, this will have an expansion (heat at 35C) and contraction (cold at -17C).

The concern that repeated Temperature Cycles will lead to a breakage of these containers which can be disastrous.

Hence, after discussing with QRA's experienced engineers, we devised a Temperature Cycle as shown below for them below : 

                                     Stress Screening Test Cycle suggested by QRA 

       Going Above and Beyond the Operational Temperature experienced by the  

                                                                  Containers. 

We suggested a Stress Screen Test, of roughly 200 cycles. Each cycle is 5 hours long, and the 200 cycles is expected to run for 1000 hours (or 200 multiplied by 5 hours) or 41.67 days. (42 days) 

The reason for the lower cold zone temperature and the higher hot zone temperature is the basis for the stress screen. Always subject the test samples to worse zones of temperature than they will be subjected to - in the end, only robustly designed samples will make it. 

Subject the test samples (containers) to extremes of temperatures, so that in test failures (cracks) are observed IN THE FACTORY and these weaknesses (material or otherwise) can be rectified before sending out the samples into the field.

The Stress Screen Test was carried out late last year and our MNC customer was very satisfied with the result.

All 3 containers passed the Stress Screen Test of 1000 hours. No cracks, delaminations or anything broken.

QRA has the distinction of doing its part in making Singapore a safer place to live, work and play.

For more information ; please email 

E : qrasales@qra.com.sg

     mark@qra.com.sg

W : www.qra.com.sg.

Shenyang Ku Gong Palace Visit - 3rd July '26

A recent visit to Shengyang China, unveiled a pleasant surprise. Our hosts, Hyperbaric Manufacturer Canta Medical Systems brought us to visit the Chong De (the last Manchu emperor) palace called Ku Gong. China was ruled by the Manchu (Qing dynasty) for almost 3 centuries before the formation of the Chinese Republic in early 1900s (1912 I believe). The first President of China was San Yet Sen. The last emperor was Pu Yi.  

Shengyang was the old capital city before it was moved to Beijing. 

There is the much larger palace in Beijing called the Forbidden City. The buildings there are very similar to the Cu Gong in Shenyang except much larger. 

It is a sprawling place, with easily 3 million square feet in area. There were many courtyands, as well as the sleeping quarters for the emperor and his officials.

With our principal host and guide Karen. 

The signs of technology and culture is apparent for all to see, and when we were there, our gorup of 15 were the only foreign tourists visiting. The vast majority were Chinese national or local tourists.

Many were dressed in the old imperial clothes of the emperor (yellow) or the empress or princesses.

One needs to be relatively fit to climb up and down the stairs to visit the palace and their buildings. 

Sheng Ji Soya Sauce Chicken - Best Tasting in the World

 

Located at the corner of Geylang Bahru Hawker Center, is this stall called Sheng Ji Soya Sauce Chicken. Run by 2 sisters in their 70s, the stall offers chicken rice, braised chicked Stewed feet (for collagen) and chicken noodles.

Last Saturday, after my run at ECP, I tried it out, just for fun. I had ventured and used the basic social science principle. If there is a queue of people waiting to order the food, it MUST be of a certain standard.

I was not disappointed. The soya sauce chicken was the best I have had in years. I am not even a soya sauce chicken rice fan, but one bite and I was in gastronomic heaven.

The meat was tender and the skin, was oh so flavourful. The rice was nice and not clumpy.

The 'jiao zhi' or dumplings were robust and had the nice water chestnut inside to give it the crunchy feel. Some other folk who were in front of me ordered like half a chicken with 2 big bags of noodles (yellow mee kia and white kway teow)

I ordered the S$ 8 (with more ingredients or jia liao) and it was an extremely satisfying lunch and so cost effective.

I plan to buy this meal for my family very soon.

Shen Ji   

69 Geylang Bahru (Hawker Centre)

#01-13 (at the far end of the hawker centre)

SGP 330069

Rating 

Taste : 4.9 / 5

Price (Value for money) : 5 / 5

Ambience : 3 / 5 (Hawker Centre environment no air conditioning).

QRA'S athletic chambers for worldwide sports clients

                           Athletic chamber for up to 4 athletes at Sport Singapore

Presenting QRA's athletic chamber with control of the following parameters listed below :

a) Temperature

b) Humidity

c) Sunlight

d) CO2 removal

e) Altitude

f) Rain

QRA is only one of four worldwide manufacturers or system integrators of athletic chambers for enhancement of elite sportsmen. There are numerous studies showing that the Live HIgh Train Low and High program has its benefits on sports performance. (LHTLTH). 

The basic concept of altitude training is such :

> At sea level (or 20.9% O2), the average person consumes O2 and his VO2 max helps convert the oxygen together with the ATP (produced from mitochondria in our red blood cells) into energy to produce work.

> Within each cubic centimeter of blood, there is (for example) 10 buckets of haemoglobin which carry the O2 to the various parts and these are functioning well. So if there are 10 buckets and O2 at 20.9% is considered as 1 unit, then the work done is 10. Or 10 x 1.

> At higher levels, where the air is thinner (at base camp Mt Everest at 5000 m), the O2 is something like 16.5 % or 2/3rd the O2 level at sea level. Logically speaking the person who has 10 buckets of haemoglobin will then function at 10 x 0.67 or 6.67. Hence every step he takes is only at 2/3rd the energy since O2 is crucial for the work to be done by the human body.

> With controlled environment, where the athlete (or person) is sleeping at 16.5 % for up to 2 weeks, he will amazingly produce (if that is the right word) more haemoglobin buckets to compensate for the low 02. So with adequate sleep and activity at the higher altitude (we call it acclimatization), our bodies will eventually create up to 15 buckets of haemoglobin, so as to produce 10 output. 15 x 0.7 is 10 at higher altitude. 

> The sleep rooms at high altitude (Sports Singapore has the facility) produce these environments for sleep and daily activity, so after roughly 2 weeks, the athletes would have 15 buckets of haemoglobin.

> Now if they were to train or run races  at 20.9%, their output work done will now be 15 x 10 or 15 which is 50 % more than what they were previously. 

> This means a tremendous improvement in performance, sportsmen will actually run faster, and produce a lot more energy especially at races or high level games like football, basketball tennis, the list is endless.

> Imagine running 30% faster than your opponent who once was as fast as you !

> You would be able to reach the ball quicker, your reaction time would be faster and you would score many more goals than any other ordinary player. Its a dream ?

Why dream ?

The reality is here.

Contact :  

mark@qra.com.sg 

qrasales@qra.com.sg 

for more information  

or visit 

website : www.qra.com.sg.

1,000,000 Views. Thank you and this post is dedicated to my family

 

John, Mum and Papa (1987) 

This blog will hit 1,000,000 views in the next day or two. I wish to dedicate this milestone to my beloved parents, Geoffrey, Anna as well as to my younger brother John. 

Though my parents are not here in this world anymore, I believe somewhere they would be happy  sharing with me on the quiet satisfaction on reaching this milestone.  When I started this blog way back in 2008, I just wanted to keep a journal of my life journey and wrote whatever came to my mind then. 

                    May many blessings be upon you wherever you go. 

            Surely goodness and mercy be upon you and yours for the rest of your days. 

                                                      12th July 2026.