Working in the cold!

Worked on a job in Sweden (-15 to -35 celcius ambient air temp).

Simply put no steel erection and no welding. (Mind you that was a Swedish workforce who were less than co-operative at the best.)

They reckoned it was not possible to weld or erect steel in those temps due to the danger of slipping on ice covered steel, hands sticking to cold metal, operation and plant and equipment in that temperature range (In specific the increased tempo of maintenance that would be required to keep plant operational and safe to use) and the less than remote risk of frostbite leading to claims.

That was my experience - sorry if its not much help but those were some of the key issues which I thought might be usefull in a practicle sense.

I’ve been working on-site in the oilsands in Fort McMurray, Alberta, Canada, and in the winter the temperature is normally -40C - very cold.
A lot of machinery becomes brittle at that temperature, so very little work is done of any kind unless there is heating and hoarding.
But as a productivity factor, we were using 40% of normal to estimate the durations under those conditions.
Hope that is helpful.

Hi Robert,
Thanks for the info, which prompts one other question:
If the ambient temperature drops to (only!) – 20 Deg C (as opposed to the -40 degrees to which you refer), is the effect on productivity proportional, or is there a point where productivity level drops to 40% and bottoms out?

David,
Thanks also for your input; again a similar question arises from your comment:
Is there a point below freezing (or even above freezing) where it is simply dangerous/impractical to erect steel? I fully appreciate that steel erection cannot be executed at say -35C; can it be executed at say -5C ?

Your views are much appreciated.

Thanx

Stuart

www.rosmartin.com

Stuart:

I looked into my library and found a book titled Human Factors/Ergonomics for Building and Construction by Martin Helander, published by John Wiley & Sons, Inc. 1981. There might be a later edition. This book has a short section about productivity under exposure to cold, which I am transcribing below:

"Few empirical data exist concerning the effectts of environmental temperatures on construction productivity. Data on mason productivity in the United States are available (Grimm and Wagner, 1974), and it has been estimated that for ambient temperatures outside the range from 7 to 32C, productivity declines about 10% per 5C, and declines more rapidly in the heat than in the cold (National Electrical Contractors’ Association of America, 1974)."

The complete references are as follows:

"Grimm, C. T., and Wagner, N. K. Weather Effects on Mason Productivity. Proceedings of the American Society of Civil Engineers, 100, 319-335, 1974."

"National Electrical Contractors Association of America, The Effect of Temperature on Productivity. Washington, D. C.: 1974."

The above information might help you also to research for up to date information.

Tomas Rivera
Altek System
Detailed Scheduling an Control of
High Performance Construction Projects

Hi Tomas

Thanx very much for the info on working in the cold; very informative especially your comment about productivity dropping by 10% for every 5C, and I managed to get the Grim & Wagner paper on the Internet.
It helps a lot – much appreciated and thanx again!

Stuart

www.rosmartin.com

Hi Guys,

I find Tomas Ribera quotation quite interesting, as although I do not have experience of extreme cold, I have extensive experience on the hot side. I do, however, find that sometimes production rates are subjective, and do not take factors into account such as where the workforce comes from, as well as where in the world the jobsite is, ie if you took people from near the equator to Siberia, and vica versa, the normal production norms would fly out the window.
To give you an idea, people in Central Africa dress up in coats when the temp falls below 20°C. Obviously if you used Siberians or Innuits, who are used to the cold, in severely cold conditions, you would get better productions, but the question would be, do they have the right experience for the job? This means the quotation is probably right in 80% of cases, but not always true in all cases. The envelope quoted ie 7°-32°C could vary either way by as much as 10°dependant on the origin of the workforce.

Regards ,

Philip Jonker