Street lighting maintenance in China (early 1990's)

I stumbled upon this interesting photograph by chance on a book we have at home filled with pictures of China - sadly this photo isn't captioned. Seems a bit of a dangerous way to change some lamps! The installation certainly looks old and would have no doubt featured globes over each lamp, which must have been removed for maintenance. The lamps themselves are undoubtedly BT mercury lamps of local manufacture, given that this book was published in the early 1990's.