One of the obstacles to building high rises year-round is that concrete does not dry or ‘set up’ in cold temperatures. A solution has been found in providing a heat source and ‘containing’ the heat with tarps around the perimeter of the building, as pictured here.

One way to heat the concrete is with propane ‘salamanders’, the preferred method in most of the world. The use of these heater in New York, however, is complicated by a NYFD prohibition against storing propane cylinders inside buildings.

‘Petcoke’ or ‘coke’ burning stoves are a cheaper than paying for expensive labor to keep moving propane, and it is mostly for this reason that this alternative has been adopted. But their open flame, rusted metal pots and potent fumes strongly suggests an archaic technology and environmental hazards.

It is worth noting that coke stoves were actually outlawed by the NYFD in 2008 because of fire safety issues arising from their open flame while in use and for the material’s combustibility. The ban, however, was overruled in 2014, presumably in response to industry pressures.

Any concrete company using coke stoves in New York today must, of course, comply with the OSHA standard which calls for providing both air monitoring and making available Safety Data Sheets. The SDS that are widely circulated, however, reference the material in an unheated state that do not address the fumes.  

In practice, workers inside containments are rarely if ever found wearing supplied air respirators that NIOSH would recommend where levels of carbon monoxide are exceed, as often occurs. There is little useful information provided to workers who have been known to don filtering-type respirators that, in oxygen-deficient atmospheres, actually make matters worse.

So, what are the health hazards associated with the burning of Coke? On top of issues relating to oxygen deficiency already discussed, the fumes created by burning petcoke to heat concrete are known to cause cancer!

For the reasons provided, coke stoves for heating concrete should be outlawed in New York City.