by Michael Cetnar, Regional Manager and Safety Specialist - ConForms

Concrete delivery systems are used every day in the concrete pumping industry. The big questions are, “Am I using the right products? If I have an accident or issue, to what standard or regulation am I going to be held accountable?”

In the concrete pumping and shotcrete industry, there are not many regulations that apply (except in British Columbia, Canada, due to recently enacted legislation). There is almost no delineation in professional publications ASME (American Society of Mechanical Engineers) B30.27, CSA (Canadian Standards Association) Z151, ACI (American Concrete Institute) 304.2R, ACPA (American Concrete Pumping Association) Safety Manual, or pump manufacturer owner’s manuals that differentiate shotcrete pumping from concrete pumping. In the context of this article, we will treat them the same. One exception is dry shotcreting (often referred to as gunite). This is due to air being the main means of conveyance of the material through the placement line instead of using a hydraulic pump to push it.

Safety professionals and safety organizations are going to lean on ASME B30.27 if they are in the U.S. or the CSA Z151 if in Canada. OSHA in the U.S. and Work Safe in Canada will also look to these standards if there is an accident. These will be the most common safety standards to which concrete pumping companies will be held. The good thing is that the ASME and the CSA are in alignment with their safety standard publications; they nearly mirror each other in language and intent.


Most concrete pumps will have a machine tag on them that states the maximum working line pressure exerted when pumping. If it is not on the machine, look in your owner’s manual or contact the manufacturer of your machine. It is important to note that maximum hydraulic pressure is related to working line pressure, but they are two different things.

The maximum concrete line pressure will be the basis of what delivery system is safe for you to use on the job. As material is being actively pumped, the line pressure will be the highest at the machine’s pump outlet and will reduce as you pump further away from it. However, if a plug develops, the entire delivery system becomes charged to the maximum

line pressure of the concrete pump. It is for this reason the entire delivery system is built around the maximum concrete line pressure of the machine. In the event of a plug, a lesser-rated delivery system can fail without warning, causing serious safety issues, potential property damage or injury.

ASME B30.27 Section 27-1.10 and CSA Z151 Section both state that all components of the delivery system must withstand the maximum material pressure of the connected pumping equipment. The manufacturer owner’s manuals, the ACPA safety manual and ACI 304.2R section 4.7.1 also include similar statements. These publications also note that all delivery system components must have a minimum burst pressure of a 2:1 safety factor when new.


The next component of having the proper delivery system is verifying that the product you are using meets the maximum working line pressure. ASME and CSA require that all delivery line, hose and accessories be marked with the maximum working pressure when new. They also require that the labels have a manufacturer’s part number, the internal diameter and a weight per foot when filled with concrete (FWC).

It is important to contact the manufacturer of the delivery system to verify how to check wear on the components as they get thinner due to use. The delivery system must be inspected and tested regularly as it wears to verify that it can still hold the maximum working pressure of the pump. ASME and CSA require frequent inspection of the delivery system in use.

Clamps are especially important to check for pressure. Most manufacturers cast the working pressure into the clamp in order to have a durable marking that is easy to read and locate. Grooved-end fittings are prohibited by the ASME and CSA in concrete pumping applications. Grooved connections have two issues that affect their ability to handle the higher pressure of today’s concrete pumps.

First, the groove does not have enough depth to hold the clamp in place to maintain the pressure at the required 2:1 or greater safety factor. The bigger issue with the grooved connection is that the groove is cut into the metal, which is part of the material that is worn as it is used; the engagement area where the clamp is connected weakens and can fail without warning. Grooved-end connections are generally rated at 300 psi. This rating may seem high, but concrete boom pumps are rated at 1,233 psi for working line pressure, and some concrete trailer pumps are rated at more than double that capacity. Clamps that use a raised end (like HD or heavy duty) provide a safer connection and will have a much higher working pressure rating than grooved clamps.


The last thing to consider in your delivery line selection is CPMA (Concrete Pump Manufacturer’s Association) Certification. The CPMA audits the manufacturers and suppliers of the components. They verify that the items have documentation and engineering data to back up the stated pressure ratings, and that laboratory testing was performed to verify engineering data. This certification must be done periodically to verify compliance with the ASME safety standard. This certification also gives you confidence that the ratings on your delivery system are indeed valid and not only a sticker stating the information.

It is strongly encouraged to get a copy of the ASME B30.27 or CSA Z151 Safety Standard depending on the area of North America in which you are working. Both publications have become the standard that construction safety professionals are using to promote safety.