Caution with concrete

Pumping concrete is often required in residential builds and, while builders don’t usually carry out the work themselves, ensuring the site remains safe during the process is everyone’s responsibility.

Pumping is an efficient method of moving and placing concrete, used in the manufacture of pre-cast and tilt-up panels, concrete formwork, slab construction, concrete paving and concrete spraying – and, like any process during a build, safety should be front of mind.

Everyone onsite has a responsibility to ensure safety measures are followed, while employers have obligations under the Health and Safety in Employment Act 1992 (the Act) to prevent harm to employees, contractors and others.

This article provides practical guidance about the health and safety issues of concrete pumping, with guidance for principals, employers, contractors and pump operators (employees or contractors) on how to meet their obligations to provide the safest working environment possible.

1)  Manual handling hazards

An employer has a duty to identify and control hazards, including hazardous manual handling tasks. These tasks must be assessed and, if the potential for serious injury is determined, control measures should be put in place to reduce the likelihood that harm will occur.

2)  Cement hazards

Overseas research shows that 5%-10% of construction workers may be sensitised, or allergic, to cement. Exposing the skin to cement can cause both irritant and allergic dermatitis.

Irritant dermatitis occurs because the abrasive and drying nature of cement on the skin causes it to become dry, itchy, red and scaly. Allergic dermatitis is caused by a person becoming allergic to a chemical component in the cement, usually chromium salts. This usually occurs upon skin exposure to wet cement. Repeated exposure to cement can lead to allergic contact dermatitis.

The more often the person is exposed, the worse the dermatitis becomes.

Those affected may have to leave the industry, if the condition becomes serious.

The symptoms of dermatitis usually show within 24-48 hours of cement exposure.

” Overseas research shows that 5%-10% of construction workers may be sensitised, or allergic to cement

Depending on the severity of exposure, symptoms include:

• A red rash or bumps on the exposed skin.
• Itching, sometimes severe.
• Dry, cracked, red patches resembling a burn.
• Blisters that drain fluid or become crusted.
• Pain, tenderness or heat on the exposed skin.
• Scaly, raw or thickened lesions.

Some components or additives in the cement are classified as hazardous substances. This means that the cement supplier has to provide the person in charge of the place of work with safety data sheets. Safety data sheets contain useful information on how to keep safe when handling the concrete, what to -do if an emergency occurs or if significant health reactions occur.

Wet cement can cause burns, if trapped against the skin. Personal protective clothing or equipment such as gloves or boots must not allow wet cement to be held against the skin.

However, if this occurs, it is important to immediately wash the area with soap and water to remove cement from the skin.

Controls for working with wet cement

• Wear appropriate protective clothing and equipment: gloves, safety goggles (if splashes to the face could occur), long clothing, waterproof footwear.
• Remove footwear/clothing immediately and wash skin with a pH-neutral soap and water if direct contact with concrete occurs.
• If the symptoms of dermatitis appear, see a doctor as soon as possible for treatment.

 

Hazard	Controls
Access points During set-up, pump workers manually handle items such as timber pads, reducers, pipes and hoses. When handling these items, the terrain or the access to the work area may increase the risk of injury.	Where practicable, establish walkways around the site and keep it clear of obstacles and debris. Provide non-slip ramps where workers are required to walk up inclines.
Using tools The use of hammers on clamps and the flapper box lever, if carried out in areas of restricted access, are tasks that may create an increased risk of injury due to working in cramped positions.	Ensure that impact tools are kept in good condition; wear appropriate protective equipment, such as eye protection. Where practicable, ensure there is plenty of space to move.
Hose handling The incorrect positioning of the pump, ineffective boom placement, wind forces or oscillation due to pumping may cause the hose-hand to forcibly restrain the hose in the required position, risking strain injuries.	Plan the work before the pour commences, to ensure that the hose-hand can work in the optimal area.
Pipe work The laying out of pipes is a task that requires carrying bulky objects. The risk of injury presented by this task can be increased by walking long distances and the need to manoeuvre pipes around obstacles.	Where practicable, use mechanical equipment to lift and move bulky objects. Position bulk stores of equipment as close as practicable to labour sites to minimise carrying.
Obstacles Bending one’s back to move beneath objects, and stepping over obstructions whilst carrying pipes increases the risk of injury.	Where practicable, establish walkways that are kept clear of debris. Use mechanical equipment to lift pipes over objects or up to higher floors.
Loading/unloading The location and design of the storage points on the truck for things like pipes, hoses, reducers and outrigger pads have a bearing on the operators’ postures and the distance these items must be carried.	Position the truck as close as practicable to the concrete pour site. Do not use hoses longer than specified by the concrete pump manufacturer.
Clearing blockages Clearing blockages in pipelines can be a highly hazardous task, as their removal may release built-up air pressure. This may also be the case during clean-up or when removing and inverting the hose reducer to empty out concrete.	The end of the hose should not be enclosed by metal. Ensure that other personnel are kept clear of the pour area. The end-hose should not be longer than what the concrete pump manufacturer recommends.Operators should be trained in how to recognise potential air blockages in the hose. Eg: when first starting, re-starting after moving, when the hopper is empty, if the concrete is too stiff and when the  pump is reversed sometimes it may not be possible to predict when an air blockage has occurred.

About this guidance

This is an excerpt from MBIE’s Concrete Pumping Health and Safety Guidelines, which provides practical advice about the safe operation and maintenance of concrete pumping equipment. The emphasis is to ensure a safe working environment whenever this equipment is used.

They are not intended to be an all-encompassing design, maintenance and operation manual. This information is available in manufacturers’ operating manuals.

This document is based on the current knowledge of construction methods within the industry, and is not intended to exclude other methods or processes that can be shown to meet the requirements of providing a safe workplace under the Act.

The guidelines were prepared by a committee of representatives from the Concrete Pumping Association of New Zealand (CPANZ) and underwent a public consultation process. This resulted in submissions from a range of affected parties, including the self-employed, employers and employees within the industry.

Consultation with the Ministry of Business, Innovation and Employment ensured overall compatibility with occupational health and safety legislation and technical alignment with standards.