THE EFFECT OF MATERIAL ELEMENTS ON ENVIROMENT BUILDINGS AND HUMAN
BUILDING CONCRETE: ELEMENTS ALL:
Moisture and sea salt increase the risk of corrosion of reinforcing steel in concrete exposed to
marine environments with poorer quality concrete or where there is less concrete cover to the steel.
The moisture and sea salt work their way in through (porous) tiny cracks, rust occupies 3x more
space than the steel it forms from the increased volume created as steel rusts can lead concrete to
spall or flake off. More extreme entire concrete structural elements can fail. Corrosion of concrete
reinforcing steel is a common cause of poor concrete durability in New Zealand. One solution to this
is more concrete cover to reinforcing and better-quality concrete. NZS 3604:2011 gives minimum
cover requirements for concrete foundations of buildings within its scope. This standard requires 25
MPa concrete for reinforced concrete exposed to weather in coastal areas. NZS 3101:2006 Concrete
structures standard – Part 1: The design of concrete structures gives minimum values for cover
thicknesses to achieve minimum durability requirements. This standard relates to environmental
conditions and exposure classifications from low to aggressive environments. Other solutions for
enhanced durability may include using reinforcement with higher resistance to chloride-induced
attack. This typically includes hot-dip galvanized steel and/or stainless steel that can minimise the
risk of steel corrosion and concrete spalling and make a cost-effective contribution to the durability
of the concrete.
HUMAN EFFECT
Cement-based concrete is widely used and contains extremely aggressive and hazardous chemicals.
However, often not enough thought is given to the potential harm it can do to those laying it.
Concrete must be managed properly, or it can cause the following health risks:
Concrete burns
Wet concrete is a strong alkaline chemical solution which is very hazardous to skin tissue. Victims are
often unaware even after several hours that they are being burnt because alkaline chemicals damage
nerve endings first. Concrete burn injuries are extremely painful and can take months to heal. Some
treatments can require surgical treatment in the form of skin grafts. In extreme cases, the medical
complications associated with the burn may lead to amputation or even death.
Irritant contact dermatitis
Irritant contact dermatitis is a skin condition caused by the chemicals that make up concrete. The
particles that make up cement are abrasive and can injure the skin. If the skin is not given sufficient
time to recover, irritant dermatitis can develop. This condition is found in many concrete workers.
Symptoms include: Stinging, Itching, Redness, Swelling, Cracking, Blisters, Scaling, Fissures,
Bleeding, Cuts or wounds heal very slowly and infections are likely Allergic contact dermatitis.
Allergic contact dermatitis is a skin condition caused by an allergic reaction to concrete. Cementbased concrete contains hexavalent chromium which causes allergies and, in some cases, cancer.
The cumulative effect of daily exposure may take years to cause a reaction; however when it does, it
is irreversible. Allergic contact dermatitis is a common reason for concrete workers to leave the
industry.
Symptoms include: Swelling, Redness, Oozing, Cracking, Stinging, Itching, Blisters, Scaling
Silicosis and chronic obstructive pulmonary disease through exposure to cement containing silica
dust.
Full-length overalls with long sleeves and trouser legs that won’t let dust or water in
Waterproof boots, Waterproof gloves, Eye protection SHOULD BE WORN TO REDUCE RISKS!
Any clothing that has been contaminated by concrete should be washed before it is used again. Do
not allow contaminated clothing to touch skin directly.
Dermatitis can occur without skin being in contact with concrete contamination, so it is vital that
workers wash their hands before visiting the toilet and eating. Avoid using abrasive cleaning products
or alcohol wet wipes as they can damage the skin and increase the risk of injury - a mild soap is best.
Ensure all workers that may be exposed to concrete understand the risks and the necessary
precautions to take. It’s recommended you get professionals to conduct regular skin exams and
encourage workers to check themselves for signs and symptoms of concrete skin contact dermatitis.
3.1 Concrete 3.1.1 NZS 3101: Part 1 Section 3 is an acceptable solution for meeting the durability
requirements of concrete building elements subject to the following modification: Provisions in this
Standard that are in non-specific or unquantified terms do not form part of the Acceptable Solution.
Non-specific or unquantified terms include, but are not limited to, special studies, manufacturer’s
advice and references to methods that are appropriate, adequate, suitable, relevant, satisfactory,
acceptable, applicable, or the like. Such provisions must be treated as the basis of an alternative
solution proposal.
NZS 3101.1:2006 section 3 is an Acceptable Solution for meeting the durability requirements of
concrete building elements subject to using only quantified terms in the standard.
Where unquantified terms – such as special studies, manufacturer’s advice, references to methods
that are appropriate, acceptable, applicable are used – it must be treated as an alternative method.
Concrete structural elements are known to have good fire performance. Concrete is non-flammable,
non-combustible, and more robust in fire than other structural systems as it can absorb a greater
amount of heat before reaching breaking point.
Concrete and concrete masonry is a highly durable construction material with low maintenance
requirements, well-designed concrete structures can be expected to exceed the minimum life span as
specified in the New Zealand Building Code.
We must make sure we use concrete with acceptable building elements to ensure the integrity of
building materials / structures as concrete and other elements have negative effects on each other
when used simultaneously. For example concrete masonry and aluminium are incompatible so we
use stainless steel.
ENVIROMENTAL EFFECT
Wastewater
Wastewater produced when working with concrete is toxic - it takes one million litres of water to dilute
one litre of alkaline back to a safe pH level (between six and seven). Use these four steps to ensure
runoff doesn’t pollute waterways, potentially killing fish and plants:
Check the weather and pick a dry day, Contain the wastewater by making a bunded area, Capture the
wastewater in the bunded area, Clear the wastewater by pumping it into a container like a 1000 litre
cube.
F1.1 The objective of this is to safeguard people from injury / illness caused by hazardous agents or
contaminants on a site. FUNCTIONAL REQUIREMENT F1.2 Buildings shall be constructed to avoid
the likelihood of people within the building being adversely affected by hazardous agents or
contaminants on the site. PERFORMANCE F1.3.1 Sites shall be assessed to determine the presence
and potential threat of any hazardous agents or contaminants. F1.3.2 The likely effect of any
hazardous agent or contaminant on people shall be determined taking account of: (a) The intended
use of the building, (b) The nature, potency or toxicity of the hazardous agent or contaminant, and, (c)
The protection afforded by the building envelope and building systems.
New Zealand is somewhat self-sufficient in concrete, and the associated materials required for its
production. Along with the fact that ready mixed concrete is generally produced locally within (NZ) to
where it is cast, this means that concrete more than meets the sustainable development principle of
products being consumed near to the place of their production.
The thermal capacity of concrete and concrete masonry, often referred to as its thermal mass,
enables it to absorb, store and later radiate heat.
The use of concrete and concrete masonry in homes enables reduced energy consumption for
heating through improved airtightness. Further savings can be achieved as a result of concrete’s
ability to reflect natural light and therefore reduce the need for artificial lighting.
REFERENCES
The New Zealand Building Code (NZBC) is the compliance framework to which all buildings in New
Zealand must conform. It sets the minimum legal requirements for building work in NZ. The New
Zealand Building Code is a schedule of the regulations authorised by the Act. It contains the
mandatory provisions for meeting the purposes of the Act and is performance based. This means it
says only what is to be done not how to do it.
Stability

B1 Structure

B2 Durability

C Fire Safety
Moisture

E1 Surface Water

E2 External Moisture

E3 Internal Moisture
Safety of Users

F4 Safety from Falling
Services and Facilities

G4 Ventilation

G7 Natural Light
Energy Efficiency

H1 Energy Efficiency 7.0 Aluminium
complying with the Building Code and must be accepted by BCAs as demonstrating compliance with
the related clauses of the Building Code. Using them is not mandatory.
ttps://www.nzsteel.co.nz/sustainability/
https://www.sitesafe.org.nz/guides--resources/practical-safety-advice/cement/