According to the NFPA 70E, Arc Flash is a “dangerous condition associated with the release of energy caused by an electric arc.” It is measured in terms of arc flash incident energy E (AFIE), which is used to determine the level of Personal Protective Equipment (PPE).
An arc flash is the light and heat produced from an electric arc supplied with sufficient electrical energy to cause substantial damage, harm, fire, or injury. This can occur near high power electrical equipment such as transformers, service entrance switch gear or generators.
The first step to protection conduct an Arc Flash Hazard Analysis which defines the procedures and limits the damage of electrical arcs on personnel and, by measuring the released energy, defines the risk and determines the relevant level of the PPE required.
|HRC* 0 – 0 cal/cm2 ; 0 J/cm2:||Non-melting, flammable materials (i.e untreated cotton, rayon, wool, silk or blends of these materials) with a minimum fabric weight of 150g/m2|
|HRC* 1 – 4 cal/cm2 ; 16,74 J/cm2:||Arc Rated Flame Retardant shirt, Flame Retardant trousers or Flame Retardant coverall|
|HRC* 2 – 8 cal/cm2 ; 33,47 J/cm2:||Arc Rated Flame Retardant shirt, Flame Retardant trousers or Flame Retardant coverall|
|HRC* 3 – 25 cal/cm2 ; 104,6 J/cm2:||Arc Rated Flame Retardant shirt and FR trousers or FR coverall, and arc flash suit selected so that the system arc rating complies with the required minimum|
|HRC* 4 – 40 cal/cm2 ; 167,36 J/cm2:||Arc Rated Flame Retardant shirt and FR trousers or FR coverall, and arc flash suit selected so that the system arc rating complies with the required mini|
*HRC: Harzard/Risk Category
Selecting the correct level of Arc Protection Equipment (APE) is made easy from this table however there are a few questions to ask your APE supplier:
- Is the garment compliant with SANS 724:2010, NFPA 70E:2009 and SANS 984/IEEE Std 1584?
- Can they send you the relevant certifications?
- Does the garment meet your required HRC level?
- Has the garment been tested? (not the fabric – very important)
- If so, can they send you the test reports that include photos?
It’s important to note that where more than 40cal/cm2 APE is required it is not recommended unless all other means of reducing the risk of exposure has been investigated.
The Arc PPE you use really is your last line of defence, and following the above steps ensures that you are doing the best you possibly can to minimise injuries as a result of an arc flash incident.
Information supplied by: Dromex Personal Protective Equipment.
Operating a loader, or any other type of machine can be a dangerous activity if certain guidelines are not followed. A good understanding of working environments and machine capabilities is critical for safe operation.
Listed below are guidelines to follow before, during and after operating a loader (N.B. not all inclusive; always refer to operation and maintenance manual for complete instructions).
Before operating the loader:
- Obtain a pre-shift checklist if available and complete it accurately. It is important to always record the results of inspections.
- Review the operation and maintenance manual before operating; know the safety precautions.
- Inspect the condition of the tires or track shoes for excessive wear, cracks and bulges.
- Verify all fluids are at the right levels.
- Inspect the condition of the bucket, nuts, bolts and other wear items for cracks or damage.
- Verify that there are no rocks, debris or other material that could fall back into the cab.
- Always wear the proper personal protective equipment for the job. Some applicable forms of PPE include; leather gloves, protective helmets, eye and ear protection and steel toe boots (make sure work boots have good tread).
- Use caution accessing and exiting the cab of the machine; maintain three points of contact at all times.
- Verify all gauges are working properly and the inside of the cab is ready for safe use.
Operating the loader:
- Always wear a seat belt and honk horn before moving the loader.
- In cold conditions, start the engine and let it run at idle speed for 15 minutes before operating; exercise the bucket up and down a few times to warm the hydraulic oil.
- Never exceed speed limits and do not make sharp turns or aggressive moves.
- Never operate on an incline with the load in the raised position (doing so could results in tipping the load or loader).
- Do not exceed the rated loads for the equipment; always attempt to center the load to the bucket when loading and unloading.
- Always be aware of surroundings – Use a spotter and know where pedestrians, objects, overhangs, fall hazards, uneven conditions and other vehicles are at all times.
After operating the loader:
- Let the loader run at idle speed for 5 minutes before completely shutting down.
- Lower the bucket to ground to avoid stress on hydraulic systems.
- Clean the loader off with high pressure water before any mud or debris hardens.
- Inspect and verify the same items before you operated the loader (see above).
- Shut off the engine before refueling.