Thinking ahead helps. Try to bring up everything you might need for the repair on the first trip up to the roof — the fewer trips up and down the ladder, the better. However, this rarely works, and most times you forget something and may need to get off the roof and get it. Do not carry any tools or equipment when ascending or descending a ladder, as this creates an unnecessary safety hazard. A practical and safer approach is to use a rope and bucket. Place the necessary items into a bucket and rope them up.  

Always follow the normal safety precautions associated with ladders. One important rule is to always have three points of contact on the ladder when ascending or descending. This means having at least both hands and one foot, or one hand and both feet, in contact with the ladder. Always inspect a ladder for damage before using it. Do not use it if there is any noticeable damage. The base of an extension ladder should be spaced one foot away for every four feet it reaches up. The ladder should extend at least three feet beyond the roof. 

While working on a roof, work carefully to prevent damaging any of the roofing material. Avoid dropping any material onto the roof that could potentially cut into it, such as screws or equipment panels. While brazing or soldering, make sure to protect the roof from any potential damage. Also, do not leave any old parts or refrigerant cylinders on the roof. Not only is this unprofessional, but it can also lead to roof damage or be a safety hazard. Although it takes extra time and effort, you should always take these items off the roof when the repair is done. 

When installing or making a repair that requires the refrigerant to be removed from a system, consider putting on access valves at the evaporator. This may help to reduce what you need to bring up onto the roof. Many evaporators will already have a suction access valve on the system, so you may only need to add on a liquid access valve. This is definitely a plus when you need to evacuate a system and add refrigerant. 

Working on rooftop equipment is an inconvenience for any service technician, but it is a necessary part of the job. Just remember to work safely and plan the job to make as few trips up and down a ladder as possible.