Roobuck is a pioneer of the cordless cap lamp concept. We designed the world’s first intrinsically safe cordless cap lamp in 2006 and certified it in IECEx. Roobuck has manufactured and supplied cordless cap lamps internationally for numerous global mining companies. This article is based on our 15 years of design, certification and application experience.
Brightness specification is always measured at the peak point of the light beam. The more focused the beam is, the higher the illumination rating. Manufacturers typically use this tactic to achieve impressive lux ratings. In real life, miners do not like the beam too focused. They need light spread out in most situations, such as walking, so they have a wider view of light. When choosing a cap lamp, test the light pattern rather than relying on the marketed specifications.
Based on our experiences, any cordless cap lamp heavier than 170g is hard to use. It is cumbersome on your head, leading to neck pain and can make you feel unbalanced. Ideally, use a cordless cap lamp less than 160g, or at most 170g.
Certified vs Uncertified Cap Lamp
All Personal Protective Equipment (PPE) is certified in Australian or international standards. Never use an uncertified cap lamp with a built-in lithium battery on your head. Short circuits and malfunctions can result in disaster; think battery explosions in a gaseous or flammable environment. Make sure the certification is Australian. This way you can trust the certification body and hold it accountable if an incident happens. International certifications can be difficult and costly to pursue compensation in case of incidents. Lastly, certification gives you peace of mind. To learn more about IECEx System go to the IECEx website.
All cordless Cap Lamps use lithium batteries, but not all battery brands are made equal. Safety is always your first concern as you wear batteries on your head. Panasonic batteries come with a good reputation. Do not be fooled by model numbers. Check the brand on the data sheet. If any Cap Lamp claims a very high battery capacity, you need to take extreme caution. There are thousands of battery manufacturers overseas. Some of them can make a battery in very high capacity by sacrificing safety. Do not use any Cap Lamp before confirming the battery manufacturer. You do not want it to explode on your head, especially when working in a gaseous or flammable environment.
As the mechanical designs of cordless Cap Lamps are similar, the material used decides the mechanical strength. The easiest way to find out the material quality is to check the temperature range specified in the certificate. The default ambient temperature range is -20°C to 40°C. If the ambient temperature is not listed in the certificate, this is a good sign, because it means this cap lamp is certified for the default temperature range. Many Cap Lamp certificates specify ambient temperatures in 0°C < Ta < 40°C, meaning the cap lamp cannot be exposed to minus temperature atmosphere verified by drop test. The testing sample is firstly conditioned in -20 degree (normally -27.5 ˚C for safety margin) unless different ambient temperature is specified by the applicant. The sample is dropped from 2m height to concrete ground for 4 times. The point of the sample torching the ground must be the most unfavorable position. Some materials of the enclosure become fragile under -20°C condition. Users need to take extreme care when using cap lamps built in this kind of materials. It is not only a temperature issue. It is a strong indication that an improper material is used for enclosure.
In QLD and NSW, IP55 is specified as minimal IP ratings for coal mines. This is a good reference for hardrock mines. However, for a peace of mind, do not use any electrical PPE less than IP66.
When a Cap Lamp is certified, its charging facilities are also tested. An improper charger may cause long-term damage or breach of intrinsically safe conditions. An easy way to check a charger is to check the certificate. Charging conditions are often specified in the Conditions of Use or the equipment description in the certificate. The formula for calculating charging time is:
If the certificate for the Cap Lamp specifies only a single charger, the certification body has verified that this Cap Lamp is at risk if it is charged from any other charging bank. Your supplier should notify you that this is a Condition of Use and if you use a different charging bank, it may be hazardous and becomes a Reportable Incident.
Angle Adjustable Light Beam
Once you have worn a Cap Lamp that you can easily adjust the angle of the beam, you cannot go back to the inconvenience of wearing a fixed beam. Make sure the Cap Lamp is actually angle adjustable as the descriptions and photos in marketing materials can be deceptive.
Well-designed Cap Lamps have three modes: standard, auxiliary and high beam. High beam mode is extremely battery intensive. This mode should automatically retreat back to main mode after a pre-set time to stop the battery draining. A miner’s worst nightmare is to run out of Cap Lamp battery in a pitch dark mine when working alone.
More Than Just a Cap Lamp
Miners often choose Cap Lamps for simple personal illumination. It is time for a rethink. Today’s manufacturers can design Cap Lamps to meet your varied or special needs, such as:
Thinly designed Cap Lamps to wear under a visor, allowing room for your visor to move up and down.
Cap Lamps with a safety beacon: The beacon is mounted on the back of the helmet to alert incoming vehicles coming from behind the miner.
Cap Lamps with a passive RFID can be used for PPE Kiosk, Electronic Tag Board or access control.
Embed functions in the Cap Lamp, such as gas detector, mini-camera and laser pointer.
Cap Lamp manufacturers can integrate wireless modules for various applications:
Wi-Fi for tracking and 2-way signalling.
LTE (Long-Term Evolution) for tracking in main tunnels.
BLE (BlueTooth) for location ID .
DSRC (Dedicated Short Range Communications) for general vehicle to pedestrian proximity.
UWB (Ultra-Wideband) for high resolution vehicle to pedestrian collision warning.
LoRa (Long Range) for environment monitoring.
NFC (Near-Field Communication) for access control.
Other wireless connections to turn your Cap Lamp into an automatic wireless data logger.
GPS (Global Positioning System) for above ground applications.
AI cap lamp is not yet available yet, however, research is under way – human behave analysis, traffic awareness and big data collection. The applications are limitless.
Finally, think of your Cap Lamp as a device beyond general illumination and talk to your manufacturer to find out what they have and what they can do for your specific applications.